91
What is the Expected Return on a Stock? Ian Martin Christian Wagner * March, 2018 Abstract We derive a formula that expresses the expected return on a stock in terms of the risk-neutral variance of the market and the stock’s excess risk-neutral variance relative to the average stock. These quantities can be computed from index and stock option prices; the formula has no free parameters. We run panel regressions of realized stock returns onto risk-neutral variances, and find that the theory performs well at 6-month, 1-year, and 2-year forecasting horizons. The formula drives out beta, size, book-to-market and momentum, and outperforms a range of competitors in forecasting stock returns out of sample. Our results suggest that there is considerably more variation in expected returns, both over time and across stocks, than has previously been acknowledged. * Martin: London School of Economics. Wagner: Copenhagen Business School. We thank Harjoat Bhamra, John Campbell, Patrick Gagliardini, Christian Julliard, Binying Liu, Dong Lou, Marcin Kacperczyk, Stefan Nagel, Christopher Polk, Tarun Ramadorai, Tyler Shumway, Andrea Tamoni, Paul Schneider, Fabio Trojani, Dimitri Vayanos, Tuomo Vuolteenaho, participants at the Western Finance Association (WFA) Meetings 2017, the 2017 Annual Meeting of the Society for Economic Dynamics (SED), the 2017 CEPR Spring Symposium, the BI-SHoF Conference in Asset Pricing, the AP2- CFF Conference on Return Predictability, the 2016 IFSID Conference on Derivatives, the 4nations Cup 2016, and seminar participants at Arrowstreet, AQR, Banca d’Italia, BlackRock, CEMFI, the European Central Bank, the London School of Economics, MIT (Sloan), NHH Bergen, Norges Bank Investment Management (NBIM), the University of Maryland, the University of Michigan (Ross), and WU Vienna for their comments. Ian Martin is grateful for support from the Paul Woolley Centre, and from the ERC under Starting Grant 639744. Christian Wagner acknowledges support from the Center for Financial Frictions (FRIC), grant no. DNRF102.

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What is the Expected Return on a Stock?

Ian Martin Christian Wagner∗

March, 2018

Abstract

We derive a formula that expresses the expected return on a stock in terms

of the risk-neutral variance of the market and the stock’s excess risk-neutral

variance relative to the average stock. These quantities can be computed from

index and stock option prices; the formula has no free parameters. We run panel

regressions of realized stock returns onto risk-neutral variances, and find that the

theory performs well at 6-month, 1-year, and 2-year forecasting horizons. The

formula drives out beta, size, book-to-market and momentum, and outperforms

a range of competitors in forecasting stock returns out of sample. Our results

suggest that there is considerably more variation in expected returns, both over

time and across stocks, than has previously been acknowledged.

∗Martin: London School of Economics. Wagner: Copenhagen Business School. We thank HarjoatBhamra, John Campbell, Patrick Gagliardini, Christian Julliard, Binying Liu, Dong Lou, MarcinKacperczyk, Stefan Nagel, Christopher Polk, Tarun Ramadorai, Tyler Shumway, Andrea Tamoni, PaulSchneider, Fabio Trojani, Dimitri Vayanos, Tuomo Vuolteenaho, participants at the Western FinanceAssociation (WFA) Meetings 2017, the 2017 Annual Meeting of the Society for Economic Dynamics(SED), the 2017 CEPR Spring Symposium, the BI-SHoF Conference in Asset Pricing, the AP2-CFF Conference on Return Predictability, the 2016 IFSID Conference on Derivatives, the 4nationsCup 2016, and seminar participants at Arrowstreet, AQR, Banca d’Italia, BlackRock, CEMFI, theEuropean Central Bank, the London School of Economics, MIT (Sloan), NHH Bergen, Norges BankInvestment Management (NBIM), the University of Maryland, the University of Michigan (Ross), andWU Vienna for their comments. Ian Martin is grateful for support from the Paul Woolley Centre,and from the ERC under Starting Grant 639744. Christian Wagner acknowledges support from theCenter for Financial Frictions (FRIC), grant no. DNRF102.

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In this paper, we derive a new formula that expresses the expected return on an

individual stock in terms of the risk-neutral variance of the market, the risk-neutral

variance of the individual stock, and the value-weighted average of individual stocks’

risk-neutral variance. Then we show that the formula performs well empirically.

The inputs to the formula—the three measures of risk-neutral variance—are com-

puted directly from option prices. As a result, our approach has some distinctive

features that separate it from more conventional approaches to the cross-section.

First, as it is based on current market prices rather than, say, accounting informa-

tion, it can in principle be implemented in real time. Nor does it require us to use

any historical information: it represents a parsimonious alternative to pooling data on

many firm characteristics (as, for instance, in Lewellen, 2015).

Second, it provides conditional forecasts at the level of the individual stock. Rather

than asking, say, what the unconditional average expected return is on a portfolio of

small value stocks, we can ask, what is the expected return on Apple, today?

Third, the formula makes specific, quantitative predictions about the relationship

between expected returns and the three measures of risk-neutral variance; it does not

require estimation of any parameters. This can be contrasted with factor models, in

which both factor loadings and the factors themselves are estimated from the data

(with all the associated concerns about data-snooping). There is a closer comparison

with the CAPM, which makes a specific prediction about the relationship between

expected returns and betas, but even the CAPM requires the forward-looking betas

that come out of theory to be estimated based on historical data.

Our approach does not have this deficiency and, as we will show, it performs better

empirically than the CAPM. But—like the CAPM—it requires us to take a stance on

the conditionally expected return on the market. We do so by applying the results

of Martin (2017), who argues that the risk-neutral variance of the market provides

a lower bound on the equity premium. In fact, we exploit Martin’s more aggressive

claim that, empirically, the lower bound is approximately tight, so that risk-neutral

variance directly measures the equity premium. We also present results that avoid any

dependence on this claim, however, by forecasting expected returns in excess of the

market. In doing so, we isolate the purely cross-sectional predictions of our framework

that are independent from the market-timing issue of forecasting the equity premium.

We introduce the theoretical framework in Section 1; then we show how to con-

1

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struct the three risk-neutral variance measures, and discuss some of their properties,

in Section 2.

Our main empirical results are presented in Section 3. We test the framework for

S&P 100 and S&P 500 stocks, at forecast horizons ranging from one month to two years.

It may be worth pointing out that papers in the predictability literature typically aim

to uncover variables that are statistically significant in forecasting regressions. We

share this goal, of course, but as our model makes predictions about the quantitative

relationship between expected returns and risk-neutral variances, we hope also to find

that the estimated coefficients on the predictor variables are close to specific numbers

that come out of the theory. For most specifications we find that that we do not

reject the model, whereas we can reject the null hypothesis of no predictability at the

six-month, one-year and two-year horizons.

In Section 4, we study how our findings relate to stock characteristics. Notably, we

run panel regressions of realized returns onto beta, size, book-to-market, and past re-

turns. Size and book-to-market are statistically significant forecasters of excess returns

in our sample period and stock universe. But when we add our predictive variables to

the regression, they drive out the characteristics as forecasters of returns; moreover,

they enter with coefficients that are insignificantly different than those predicted by

the theory. In a similar vein, we show that the returns on portfolios sorted on the

characteristics are consistent with the model.

Section 5 assesses the out-of-sample predictive performance of the formula when its

coefficients are constrained to equal the values implied by the theory. We compute out-

of-sample R2 coefficients that compare the formula’s predictions to those of a range of

competitors, as in Goyal and Welch (2008). We start by comparing against competitors

that are themselves out-of-sample predictors (in the sense of being based on a priori

considerations, without in-sample information). The formula outperforms all such

competitors at horizons of three, six, 12 and 24 months, both for expected returns and

for expected returns in excess of the market.

We go on to compare, more ambitiously, against competitors that have in-sample

information. At the six- and 12-month horizons, the only case in which our model of

expected excess returns ‘loses’ is when we allow the competitor predictor to know both

the in-sample average (across stocks) realized return and the multivariate in-sample

relationships between realized returns and beta, size, book-to-market, and past returns.

2

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Figure 1: Expected excess returns and expected excess market returns. Annual horizon.

Panel A. Expected excess returnsAPPLE INC

Exp

ecte

d E

xces

s R

etur

n

0.00

0.05

0.10

0.15

0.20

0.25

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

ModelSVIXt CAPM6% CAPM

JPMORGAN CHASE & CO

Exp

ecte

d E

xces

s R

etur

n

0.00

0.05

0.10

0.15

0.20

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

ModelSVIXt CAPM6% CAPM

Panel B. Expected returns in excess of the marketAPPLE INC

Exp

ecte

d R

etur

n in

Exc

ess

of th

e M

arke

t

0.00

0.05

0.10

0.15

0.20

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

ModelSVIXt CAPM6% CAPM

JPMORGAN CHASE & COE

xpec

ted

Ret

urn

in E

xces

s of

the

Mar

ket

0.00

0.05

0.10

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

ModelSVIXt CAPM6% CAPM

(When we allow the competitor to know only the in-sample average and the univariate

relationship between realized returns and any one of the characteristics, our formula

outperforms.)

Even more strikingly, in the purely cross-sectional case in which we forecast returns

in excess of the market, the formula outperforms even the competitor armed with

knowledge of the multivariate relationship. Given these successes, it is natural to ask

how the resulting forecasts can be used in trading strategies. We show how to do so,

and show also that the resulting strategies have attractive properties.

The empirical success of our formula is particularly notable because it makes some

dramatic predictions about stock returns. Figure 1 plots the time-series of expected

3

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excess returns, relative to the riskless asset and relative to the market, for Apple

and for JPMorgan Chase & Co. over the period from January 1996 to October 2014.

According to our model, expected returns spiked for both stocks in the depths of the

financial crisis of 2008–9. In the case of Apple, this largely reflected a high market-

wide equity premium rather than an Apple-specific phenomenon, whereas JP Morgan

Chase’s expected excess return was high even relative to the market risk premium.

The figure also plots expected excess returns computed using the CAPM with one-year

rolling historical betas (and the equity premium computed from the SVIX index of

Martin (2017), or fixed at 6%), to illustrate the point—which, as we will show, holds

more generally—that our model generates more volatility in expected returns, both

over time and in the cross-section, than does the CAPM.

Related literature. A large literature has documented the importance of idiosyn-

cratic volatility for future stock returns, though with varying conclusions. For instance,

Ang et al. (2006) find a negative relation both for total volatility and for idiosyncratic

volatility (defined as the residual variance of Fama–French three factor regressions on

daily returns over the past month). By contrast, Fu (2009) finds a positive relation

when idiosyncratic volatility is measured by the conditional variance obtained from fit-

ting an EGARCH model to residuals of Fama–French regressions on monthly returns.

Our model attributes an important role to average stock variance (measured as

the value-weighted sum of individual stock risk-neutral variances), a prediction that

we confirm empirically. This result echoes the finding of Herskovic et al. (2016) that

idiosyncratic volatility (measured from past returns) exhibits a strong factor structure

and that firms’ loadings on the common component predict equity returns. Further-

more, our measure of average stock variance may capture a potential factor structure

in the cross-section of equity options, as documented by Christoffersen et al. (2017)

across 29 Dow Jones firms.

Various authors have explored the forecasting power of options-based measures.

An et al. (2014) find that increases in implied volatilities of at-the-money call and

put options have opposing implications, predicting high and low subsequent stock

returns, respectively. Conrad et al. (2013) study the relationship between risk-neutral

moments and realized returns, and find a negative, though not statistically significant,

relationship between risk-neutral variance and subsequent stock returns; they work

with the risk-neutral variance of log returns (following Bakshi et al. (2003)), so their

4

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volatility indices load particularly strongly on the prices of deep out-of-the-money put

options. In contrast to both these papers, our theoretical results lead us to focus on the

risk-neutral variance of index- and stock-level simple returns; the resulting volatility

indices load equally on the prices of options of all strikes.

Other papers work within the CAPM and attempt to estimate betas more accu-

rately by incorporating forward-looking information from options. French et al. (1983)

estimate beta using a stock’s historical return correlation with the market and option-

implied volatilities for the stock and the market. Buss and Vilkov (2012) take a similar

approach, but estimate correlation from a parametric model that links correlation un-

der the risk-neutral and the objective measure. Chang et al. (2012) make assumptions

under which expected correlation can be computed from the ratio of option-implied

stock to market skewness; this implies, however, that a firm’s implied beta will only

be positive if its skewness has the same sign as market skewness, i.e. it will typically

not provide a meaningful CAPM beta for firms with positive skewness.

In a more closely related, and contemporaneous, paper, Kadan and Tang (2016)

adapt an idea of Martin (2017) to derive a lower bound on expected stock returns. To

understand the main differences between their approach and ours, recall that Martin

starts from an identity that relates the equity premium to a risk-neutral variance term

and a (real-world) covariance term; he exploits the identity by arguing that a negative

correlation condition (NCC) holds for the market return, i.e. that the covariance term

on the right-hand side of this identity is nonpositive in quantitatively reasonable models

of financial markets. If so, the risk-neutral variance of the market provides a lower

bound on the equity premium.1 Kadan and Tang (2016) modify this approach to derive

a lower bound for expected stock returns based on a negative correlation condition for

individual stocks. But it is trickier to make the argument that the NCC should hold

at the individual stock level, so Kadan and Tang’s approach only applies for a subset

of S&P 500 stocks.

1Schneider and Trojani (2016) propose a related approach to forecasting the equity premium basedon (among other things) variants of the NCC. They estimate the minimum variance pricing kernelunder various a priori assumptions about the moments of the market return, together with the as-sumptions that (i) the pricing kernel is a Jth order polynomial in the market return that correctlyprices the first J moments of the market return, and (ii) the realized return on the market must takeone of J + 1 values. In their empirical implementation, J = 3.

5

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1 Theory

Our starting point is the gross return with maximal expected log return: call it Rg,t+1,

so Et logRg,t+1 ≥ Et logRi,t+1 for any gross return Ri,t+1. This growth-optimal return

has the special property, unique among returns, that 1/Rg,t+1 is a stochastic discount

factor. To see this, note that it is attained by choosing portfolio weights {gn}Nn=1 on

the tradable returns (on stocks and stock options) to solve

max{gn}Nn=1

E logN∑n=1

gnRn,t+1 such thatN∑n=1

gn = 1.

The first-order conditions for this problem are that

E

(Ri,t+1∑N

n=1 gnRn,t+1

)= ψ for all i,

where ψ is a Lagrange multiplier; we follow Roll (1973) and Long (1990) in assuming

that these first-order conditions have an interior solution. Multiplying by gi and sum-

ming over i, we see that ψ = 1, and hence that the reciprocal of Rg,t+1 ≡∑N

n=1 gnRn,t+1

is an SDF.

We write E∗t for the associated risk-neutral expectation (more precisely, the time-

t+ 1-forward-neutral expectation) that is defined via2

1

Rf,t+1

E∗t Xt+1 = Et(Xt+1

Rg,t+1

). (1)

In these terms, the key property of the growth-optimal portfolio, which follows directly

from (1), is that

EtRi,t+1

Rf,t+1

− 1 = cov∗t

(Ri,t+1

Rf,t+1

,Rg,t+1

Rf,t+1

)for all stocks i. (2)

Thus risk-neutral covariances with the growth-optimal return determine risk premia.

2A helpful perspective to keep in mind is that of an unconstrained log investor who is marginalin all markets, including option markets, but chooses to invest his wealth fully in the market. (SeeMartin (2017) and Kremens and Martin (2018) for a similar approach in the context of the stockmarket and of currencies, respectively.) Such an investor must perceive the market itself as growth-optimal, so that if Et represents the expectations of the log investor, (1) and subsequent equationshold with Rg,t+1 = Rm,t+1.

6

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We start by projecting stock returns onto the growth-optimal portfolio under the

risk-neutral measure. That is, for every stock i we decompose

Ri,t+1

Rf,t+1

= α∗i,t + β∗i,tRg,t+1

Rf,t+1

+ εi,t+1 (3)

where

β∗i,t =cov∗t

(Ri,t+1

Rf,t+1, Rg,t+1

Rf,t+1

)var∗t

Rg,t+1

Rf,t+1

(4)

E∗t εi,t+1 = 0 (5)

cov∗t (εi,t+1, Rg,t+1) = 0. (6)

Equations (3)–(5) define εi,t+1, β∗i,t and α∗i,t; and equation (6) is a consequence of (3)–

(5). Thus the only assumption embodied in (3)–(6) is that the appropriate risk-neutral

moments exist and are finite, and that var∗t Rg,t+1/Rf,t+1 is non-zero. (This last assump-

tion is needed for (4) to be well defined: it rules out the theoretically interesting, but

empirically implausible, possibility that the risk-neutral and true probability measures

coincide, as in that case the growth-optimal portfolio is riskless.)

It may be helpful to compare this approach to that of Hansen and Richard (1987),

who also projected arbitrary returns onto a ‘distinguished’ return—in their case, the

minimum-second-moment return, R∗,t+1, which is proportional to an SDF so has the

key property that Et (R∗,t+1Ri,t+1) = Et(R2∗,t+1

)for all tradable returns Ri,t+1, and

hence that3

EtRi,t+1

Rf,t+1

− 1 = − Rf,t+1

EtR∗,t+1

covt

(Ri,t+1

Rf,t+1

,R∗,t+1

Rf,t+1

)for all stocks i. (2′)

This equation says that true covariances with a tradable payoff determine risk premia.

3Using one of the results of Hansen and Jagannathan (1991), this can also be written as

EtRi,t+1

Rf,t+1− 1 = −

(1 + S2

t

)covt

(Ri,t+1

Rf,t+1,R∗,t+1

Rf,t+1

),

where St is the maximal conditional Sharpe ratio at time t, using the facts that (i) Rf,t+1/EtR∗,t+1 =

Et(R2∗,t+1

)/ (EtR∗,t+1)

2by the key property of R∗,t+1; and (ii) Et

(R2∗,t+1

)/ (EtR∗,t+1)

2= 1 + S2

t ,which follows because R∗,t+1 lies (by definition) at the tangency point of an origin-centered circle tothe lower edge of the minimum-variance frontier in a mean–standard-deviation diagram.

7

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It motivates the decomposition

Ri,t+1

Rf,t+1

= αi,t + βi,tR∗,t+1

Rf,t+1

+ ui,t+1 (3′)

where

βi,t =covt

(Ri,t+1

Rf,t+1, R∗,t+1

Rf,t+1

)vart

R∗,t+1

Rf,t+1

(4′)

Et ui,t+1 = 0 (5′)

covt(ui,t+1, R∗,t+1) = 0. (6′)

We spell this out explicitly to emphasize the analogy between the two approaches. As

before, equations (3′)–(5′) define ui,t+1, βi,t, and αi,t; and equation (6′) follows from

them.4 Equations (2′)–(6′) can be viewed as the theoretical foundation of the fac-

tor pricing literature. But as forward-looking real-world covariances are not directly

observable, they must be estimated from time-series data. Such estimates will only

approximate the true forward-looking covariances if the econometric environment is

sufficiently stable (ergodic, stationary) in a statistical sense. Thus to make these equa-

tions empirically useful, one needs to make further assumptions about the stochastic

properties of ui,t+1 across assets and over time, about the stability of conditional betas

over appropriate time horizons, and about the factors that must be included to provide

a tolerable approximation to the true minimum-second-moment return.

Very broadly speaking, our approach may have a particular advantage at times

when information arrives suddenly and in lumps, whether as the result of an earnings

announcement, macroeconomic news, a terrorist attack, natural or unnatural disaster,

or something else. Backward-looking historical covariances will adjust sluggishly at

such times—which may be of particular interest to investors, decision-makers inside

firms, and policymakers who must respond rapidly to changing conditions—whereas

option prices, and hence our formulas, will react almost instantly.

That said, we will also need to make assumptions to make our approach imple-

4By taking risk-neutral expectations of (3) we see that α∗i,t = 1−β∗i,t. Similarly, by taking real-worldexpectations of (3′) and using (2′) together with the properties of R∗,t+1 mentioned in footnote 3, wefind that αi,t = 1− βi,t.

8

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mentable in practice. Equations (2) and (4) together imply that

EtRi,t+1

Rf,t+1

− 1 = β∗i,t var∗tRg,t+1

Rf,t+1

. (7)

We also have, from (3) and (6),

var∗tRi,t+1

Rf,t+1

= β∗2i,t var∗tRg,t+1

Rf,t+1

+ var∗t ui,t+1. (8)

What we would like to measure is the right-hand side of (7). What we can measure is

the left-hand side of (8) (as we will show in the next section). To connect the two, we

make two assumptions.

First, we approximate the β∗2i,t term in (8) by linearizing β∗2i,t ≈ 2β∗i,t − k, where

k is a constant. This approximation is reasonable if β∗i,t is not too far from 1 for a

typical stock.5 In Internet Appendix IA.A, we explicitly derive the residual that the

approximation neglects, and argue that it is small for most stocks in our sample. We

therefore replace (8) with

var∗tRi,t+1

Rf,t+1

= (2β∗i,t − k) var∗tRg,t+1

Rf,t+1

+ var∗t ui,t+1. (9)

Using (7) and (9) to eliminate the dependence on β∗i,t, we have

EtRi,t+1

Rf,t+1

− 1 =1

2var∗t

Ri,t+1

Rf,t+1

+k

2var∗t

Rg,t+1

Rf,t+1

− 1

2var∗t ui,t+1. (10)

To make further progress, let wi,t be the market capitalization weight of stock i in the

5If k = 1 this linearization is the tangent to β∗2i,t at β∗i,t = 1. Alternatively, if, say, the cross-section

of betas has mean 1 and standard deviation σ then one could set k = 1− σ2 in order to minimize themean squared approximation error. As we will shortly see, the precise value of k turns out not to beimportant. The choice to linearize around β∗i,t = 1 is not critical, though we think it is natural: if theequal-weighted portfolio of stocks is approximately growth-optimal, then β∗i,t is close to 1 on average,while if the market is approximately growth-optimal, then β∗i,t is close to 1 on value-weighted average.

More generally, we could linearize β∗2i,t ≈ cβ∗i,t + d for appropriately chosen c and d. For example, the

tangent to β∗2i,t at β∗i,t = β0, some constant, corresponds to c = 2β0 and d = −β20 ; or one might want

to choose c and d to achieve some other goal (e.g., to minimize the mean squared error for a givendistribution of β∗i,t). If one takes this approach, equations (14) and (15) are unaltered except that1/2 is replaced by 1/c; in particular, the value of d drops out. (See Internet Appendix IA.A.) Ourempirical results suggest that it is reasonable to linearize around 1, that is, to set c = 2.

9

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index. Value-weighting the above equation, we find that

EtRm,t+1

Rf,t+1

− 1 =1

2

∑j

wj,t var∗tRj,t+1

Rf,t+1

+k

2var∗t

Rg,t+1

Rf,t+1

− 1

2

∑j

wj,t var∗t uj,t+1. (11)

Subtracting (11) from (10),

EtRi,t+1 −Rm,t+1

Rf,t+1

=1

2

(var∗t

Ri,t+1

Rf,t+1

−∑j

wj,t var∗tRj,t+1

Rf,t+1

)−1

2

(var∗t ui,t+1 −

∑j

wj,t var∗t uj,t+1

).

(12)

Our second assumption is that the final term on the right-hand side of (12), which

is zero on value-weighted average, can be captured by a time-invariant stock fixed

effect αi. This fixed-effects formulation, which is econometrically convenient, would

follow immediately if, for example, the risk-neutral variances of residuals decompose

separably, var∗t ui,t+1 = φi + ψt, and value weights are constant over time.

It will be convenient to define three different measures of risk-neutral variance:

SVIX2t = var∗t (Rm,t+1/Rf,t+1)

SVIX2i,t = var∗t (Ri,t+1/Rf,t+1) (13)

SVIX2

t =∑i

wi,t SVIX2i,t .

These measures can be computed directly from option prices, as we show in the next

section. The SVIXt index was introduced by Martin (2017)—the name echoes the

related VIX index—but the definitions of stock-level SVIXi,t and of SVIXt, which

measures average stock volatility, are new to this paper. Introducing these definitions

into (12) we arrive at our first, purely relative, prediction about the cross-section of

expected returns in excess of the market :

EtRi,t+1 −Rm,t+1

Rf,t+1

= αi +1

2

(SVIX2

i,t−SVIX2

t

). (14)

We test this prediction by running a panel regression of realized returns-in-excess-of-

the-market of individual stocks i onto stock fixed effects and excess stock variance

SVIX2i,t−SVIX

2

t .

In order to answer the question posed in the title of the paper, we must also take

a view on the expected return on the market itself. To do so, we exploit a result of

10

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Martin (2017), who argues that the SVIX index can be used as a forecast of the equity

premium: specifically, that EtRm,t+1 − Rf,t+1 = Rf,t+1 SVIX2t . Substituting this into

equation (12), we have

EtRi,t+1 −Rf,t+1

Rf,t+1

= αi + SVIX2t +

1

2

(SVIX2

i,t−SVIX2

t

). (15)

We test (15) by running a panel regression of realized excess returns on individual

stocks i onto stock fixed effects, risk-neutral variance SVIX2t , and excess stock variance

SVIX2i,t−SVIX

2

t .

As noted above, the fixed effects in (14) and (15) should be zero on value-weighted

average. We test this prediction in two ways: first, in a weaker form, that∑

iwiαi = 0

(where wi = 1Ti

∑twi,t is the average value weight of stock i and Ti the number of time-

series observations for stock i). We also consider, and test, the stronger assumption

that αi = 0 for all i, which would hold if risk-neutral residual variance is constant

across stocks, though not necessarily across time. In this form, we are imposing a

tight relationship between a stock’s risk-neutral variance and its risk-neutral beta:

by (8), stocks with high variances must also have high risk-neutral betas. Making this

assumption in (14), for example, we have6

EtRi,t+1 −Rm,t+1

Rf,t+1

=1

2

(SVIX2

i,t−SVIX2

t

). (16)

Correspondingly, if we assume that the fixed effects are constant across i in (15), we

end up with a formula for the expected return on a stock that has no free parameters:

EtRi,t+1 −Rf,t+1

Rf,t+1

= SVIX2t +

1

2

(SVIX2

i,t−SVIX2

t

). (17)

In Section 5, we exploit the fact that (16) and (17) require no parameter estimation—

only observation of contemporaneous prices—to conduct an out-of-sample analysis, and

show that the formulas outperform a range of plausible competitors.

We note that our approach is not appropriate for all assets. Suppose, for example,

6At first sight, (16) appears to lead to an inconsistency: if we “set i = m,” it seems to imply that

SVIX2t = SVIX

2

t , which is not true (as we discuss in Section 2 below). The right way to “set i = m”

here is to replace SVIX2i,t not with SVIX2

t but with its value-weighted sum, SVIX2

t . By contrast, itis legitimate to “set i = m” in linear factor models in which risk premia are expressed in terms ofcovariances of returns with factors.

11

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that asset j is genuinely idiosyncratic—and hence has zero risk premium—but has

extremely high, and perhaps wildly time-varying, variance SVIX2j,t. Then equation

(15) cannot possibly hold for asset j. Our assumptions reflect a judgment that such

cases are not typical within the universe of stocks that we study (namely, members of

the S&P 100 or S&P 500 indices).7 This is an empirically testable judgment, and we

put it to the test below.

2 Three measures of risk-neutral variance

The risk-neutral variance terms that appear in our formulas can be calculated from

option prices using the approach of Breeden and Litzenberger (1978). Our measure of

market risk-neutral variance, SVIX2t , is determined by the prices of index options:

SVIX2t =

2

Rf,t+1S2m,t

[∫ Fm,t

0

putm,t(K) dK +

∫ ∞Fm,t

callm,t(K) dK

],

where we write Sm,t and Fm,t for the spot and forward (to time t + 1) prices of the

market, and putm,t(K) and callm,t(K) for the time-t prices of European puts and calls

on the market, expiring at time t+1 with strike K. (The length of the period from time

t to time t+1 varies according to the horizon of interest. Thus we will be forecasting 1-

month returns using the prices of 1-month options, 3-month returns using the prices of

3-month options, and so on. Throughout the paper, we annualize returns and volatility

indices by scaling by horizon length measured in years.) The SVIX index (squared)

therefore represents the price of a portfolio of out-of-the-money puts and calls equally

weighted by strike. This definition is closely related to that of the VIX index, the key

difference being that VIX weights option prices in inverse-square proportion to their

strike.

The corresponding index at the individual stock level is defined in terms of indi-

7There is an analogy with an earlier debate on the testability of the arbitrage pricing theory (APT).Shanken (1982) showed, under the premise of the APT that asset returns are generated by a linearfactor model, that it is possible to construct portfolios that violate the APT prediction that assets’expected returns are linear in the factor loadings. Dybvig and Ross (1985) endorsed the mathematicalcontent of Shanken’s results but disputed their interpretation, arguing that the APT can be appliedto certain types of asset (for example, stocks), but not to arbitrary portfolios of assets.

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vidual stock option prices:

SVIX2i,t =

2

Rf,t+1S2i,t

[∫ Fi,t

0

puti,t(K) dK +

∫ ∞Fi,t

calli,t(K) dK

],

where the subscripts i indicate that the reference asset is stock i rather than the market.

Finally, using SVIX2i,t for all firms available at time t, we calculate the risk-neutral

average stock variance index as SVIX2

t =∑

iwi,t SVIX2i,t.

We pause to note two facts about these volatility indices. First, average stock

volatility must exceed market volatility, that is, SVIXt > SVIXt. Given the defini-

tions above, this is an illustration of the slogan that a portfolio of options is more

valuable than an option on a portfolio. More formally, it is a consequence of the fact

that∑

iwi,t var∗t Ri,t+1 > var∗t∑

iwi,tRi,t+1 or, equivalently, that E∗t∑

iwi,tR2i,t+1 >

E∗t[(∑

iwi,tRi,t+1)2], which follows from Jensen’s inequality.

Second, risk-neutral variance is, as a rule of thumb, increasing in the time-to-

maturity of the underlying options (equivalently, in the length of the period from t to

t + 1). Formally, assume that the underlying asset does not pay dividends and use

put-call parity to rewrite

SVIX2i,t = var∗t (Ri,t+1/Rf,t+1) =

2

Rf,t+1S2t

∫ ∞0

calli,t(K)︸ ︷︷ ︸↑ in maturity

dK − 1.

As is well-known, if the underlying asset does not pay dividends—a tolerable approx-

imation to reality for the stocks and horizons we consider—a European call and an

American call have the same value, and hence call prices are increasing in time-to-

maturity. Assuming this is not offset by the countervailing effect of increased interest

rates Rf,t+1 over longer horizons, SVIXi,t should be expected to be monotonic in hori-

zon length. We have found nonmonotonicity to be a useful flag for detecting a small

number of extreme outliers in our data, as we discuss further below.

In our empirical work, we start with daily data from OptionMetrics for equity

index options on the S&P 100 and on the S&P 500, providing us with time series of

implied volatility surfaces from January 1996 to October 2014. We obtain daily equity

index price and return data from CRSP and information on the index constituents

from Compustat. We also obtain data on the firms’ number of shares outstanding and

their book equity to compute their market capitalizations and book-to-market ratios.

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Using the lists of index constituents, we search the OptionMetrics database for all firms

that were included in the S&P 100 or S&P 500 during our sample period, and obtain

volatility surface data for these individual firms, where available.

We face the issue that S&P 100 index options and individual stock options are

American-style rather than European-style. The distinction is likely to be relatively

minor at the horizons we consider, as the options whose prices we require are out-of-

the-money; in any case, the volatility surfaces reported by OptionMetrics deal with

this issue via binomial tree calculations that aim to account for early exercise premia.

We take the resulting volatility surfaces as our measures of European implied volatility,

following Carr and Wu (2009) among others.

We compute the three measures of risk-neutral variance given in equation (13)

for horizons (i.e., option maturities) of one, three, six, 12, and 24 months. We then

filter out a small number of extreme outliers in our data that violate the monotonicity

property in SVIXi,t across horizons described above.8 As summarized in Panel A of

Table 1, we end up with more than two million firm-day observations for each of the

five horizons, covering a total of 869 firms over our sample period from January 1996 to

October 2014. Across horizons, we have data on 451 firms on average per day, meaning

that we cover slightly more than 90% of the firms included in the S&P 500 index. From

the daily data, we also compile data subsets at a monthly frequency for firms included

in the S&P 100 (Panel B) and the S&P 500 (Panel C).

Figure 2 plots the time series of risk-neutral market variance (SVIX2t ) and average

risk-neutral stock variance (SVIX2

t ) for the S&P 500; for the S&P 100 we present these

results in Figure IA.1 in the Internet Appendix. The dynamics of SVIX2t and SVIX

2

t

are similar for both indices and across horizons. All the time series spike dramatically

during the financial crisis of 2008. While the average levels of the (annualized) SVIX

measures are similar across horizons, their volatility is higher at short than at long

horizons. Similarly, the peaks in SVIX2t and SVIX

2

t during the crisis and other periods

of heightened volatility are most pronounced in short-maturity options.9

8In the daily data, we end up with 2,106,711 firm-day observations after removing 9,648 observa-tions based on nonmonotonicity. In our monthly data for S&P 500 firms, we end up with 102,198firm-month observations after removing 401 observations based on nonmonotonicity.

9In Appendix A, we show that the ratio of market variance to average stock variance,

SVIX2t /SVIX

2

t , can be interpreted as a measure of average risk-neutral correlation between stocks.

Figure IA.2 in the Internet Appendix plots the time-series of SVIX2t /SVIX

2

t at one-month and one-year horizons for the S&P 100 and S&P 500. Average stock variance was unusually high relative to

14

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Figures 3 and 4 show the relationships between risk-neutral stock variances and

various firm characteristics, on average and in the time series. To construct the figures,

we sort S&P 500 stocks into portfolios based on their CAPM beta, size, book-to-

market ratio, or momentum, and compute the (equally-weighted) average SVIX2i,t for

each portfolio, at the 12-month horizon.10 SVIX2i,t is positively related to CAPM beta

and inversely related to firm size, on average and throughout our sample period. In

contrast, there is a U-shaped relationship between SVIX2i,t and book-to-market that

reflects an interesting time-series relationship between the two. Growth and value

stocks had similar levels of volatility during periods of low index volatility, but value

stocks were more volatile than growth stocks during the recent financial crisis and

less volatile from 2000 to 2002. We also find a non-monotonic relationship between

momentum and SVIX2i,t. Interestingly, loser stocks exhibited particularly high SVIX2

i,t

from late 2008 until the momentum crash in early 2009.11

3 Testing the model

In this section, we use SVIX2t , SVIX2

i,t and SVIX2

t to test the predictions of our model

using full sample information. But before turning to formal tests, we conduct a prelim-

inary exploratory exercise. Specifically, we ask whether, on time-series average, stocks’

average excess returns line up with their excess stock variances in the manner predicted

by equation (17). To do so, we temporarily restrict to firms that were included in the

S&P 500 throughout our sample period. For each such firm, we compute time-averaged

excess returns and risk-neutral excess stock variance, SVIX2i −SVIX

2. Equation (17)

implies that for each percentage point difference in SVIX2i −SVIX

2, we should see half

that percentage point difference in excess returns.

The results of this exercise are shown in Figure 5, which is analogous to the se-

market variance over the period from 2000 to 2002, indicating that the correlation between stocks wasunusually low at that time.

10We measure momentum by the return over the past twelve months, skipping the most recentmonth’s return (see, e.g., Jegadeesh and Titman, 1993). Our estimation of conditional CAPM betasbased on past returns follows Frazzini and Pedersen (2014): we estimate volatilities by one-year rollingstandard deviations of daily returns and correlations from five-year rolling windows of overlappingthree-day returns.

11We find similar results at the 1-month horizon: see Figures IA.3 and IA.4 in the Internet Appendix.Figure IA.5 plots (equally-weighted) average SVIXi at the 12-month horizon for portfolios double-sorted on size and value.

15

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curity market line of the CAPM. The return horizon matches the maturity of the

options used to compute the SVIX-indices. We regress average excess returns on

0.5× (SVIX2i −SVIX

2); the regression intercept equals the implied average equity pre-

mium. We find slope coefficients of 0.60, 0.79, 1.00, 1.10, and 1.01 for horizons of one,

three, six, 12, and 24 months, respectively—close to the model-predicted coefficient of

one—and R2 ranging from 0.09 to 0.18. Using the same subset of firms, the figures also

show decile portfolios sorted by SVIXi,t (indicated by diamonds) and 3 × 3 portfolios

sorted by size and book-to-market (indicated by triangles).

We repeat this exercise for portfolios sorted on firms’ risk-neutral variance SVIXi,t,

using all available firms (lifting the requirement of full sample period coverage). Fig-

ure 6 shows that average portfolio returns in excess of the market are broadly in-

creasing in portfolios’ average volatility relative to aggregate stock volatility, and that

SVIX2i −SVIX

2captures a sizeable fraction of the cross-sectional variation in returns.

To test the model formally, we start by estimating the pooled regression

Ri,t+1 −Rf,t+1

Rf,t+1

= α + β SVIX2t +γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1. (18)

Based on the formula (17), we would ideally hope to find that α = 0, β = 1 and

γ = 1/2. At a given point in time t, our sample includes all firms that are time-t

constituents of the index. We run the regression using monthly data for the S&P 100

and S&P 500 indices, at return horizons (and hence also option maturities) of one,

three, six, 12, and 24 months.

We test the prediction (15) by running a panel regression with firm fixed effects

Ri,t+1 −Rf,t+1

Rf,t+1

= αi + β SVIX2t +γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1 (19)

and testing the hypothesis that β = 1, γ = 1/2, and∑

iwiαi = 0.

Throughout the paper, we calculate standard errors (reported in parentheses) and

p-values using a block bootstrap procedure that accounts for time-series and cross-

sectional dependencies in the data. Appendix B provides further detail about the

bootstrap procedure and presents Monte Carlo simulation evidence on the reliability

of the procedure in finite samples.

The pooled regression results for S&P 100 firms are shown in Panel A of Table 2.

The headline result is that when we conduct a Wald test of the joint hypothesis that

16

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α = 0, β = 1, and γ = 0.5, we do not reject our model at any horizon (with p-values

ranging from 0.55 to 0.69). By contrast, we can reject the joint hypothesis that β = 0

and γ = 0 with moderate confidence for six-, 12-, and 24-month returns (p-values of

0.064, 0.045, and 0.012, respectively). Notice that as the estimated coefficient γ exploits

cross-sectional information, it is estimated more precisely than is β; as a result, our

results are consistently stronger in a statistical sense than those of Martin (2017).

The coefficient estimates remain fairly stable, and we draw similar conclusions,

when we allow for firm fixed effects (in Panel B). A Wald test of the joint null hypothesis

that∑

iwiαi = 0, β = 1, and γ = 0.5 does not reject the model (p-values between 0.11

and 0.36), and we can strongly reject the joint null that β = γ = 0 for horizons of six,

12, and 24 months (p-values below 0.01). The β estimates are little changed compared

to the pooled regressions, while the γ estimates are somewhat higher (from 0.734 to

1.225).

The corresponding results for S&P 500 firms are reported in Table 3. In the pooled

regression (Panel A), we do not reject the joint null that α = 0, β = 1, and γ = 0.5 at

horizons of one, three, six, and 12 months (p-values between 0.169 and 0.267). We do

however reject the model at the 24-month horizon: the estimated β is even higher than

the theory predicts. We can cautiously reject the joint null that β = 0 and γ = 0 at

horizons of six, 12, and 24 months (p-values of 0.071, 0.092, and 0.036). The statistical

results are more clear-cut when we include firm fixed effects (Panel B). Again, we do

not reject the joint null hypothesis implied by our model at horizons up to including

12 months, but can strongly reject the null that β = γ = 0 at horizons of six, twelve,

and 24 months (p-values of 0.019, 0.008, and 0.002).

To focus on the purely cross-sectional implications of our framework, we test the

prediction of equation (16) by running the regression

Ri,t+1 −Rm,t+1

Rf,t+1

= α + γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1, (20)

and (corresponding to equation (14)) a regression that allows for stock fixed effects,

Ri,t+1 −Rm,t+1

Rf,t+1

= αi + γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1. (21)

We test the hypotheses that α = 0 and γ = 1/2 in equation (20), and that∑

iwiαi = 0

17

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and γ = 1/2 in equation (21). These regressions avoid any reliance on the argument

of Martin (2017) that the equity premium can be proxied by SVIX2t , though of course

they only make a relative statement about the cross-section of expected returns. In

our empirical analysis we compute Rm,t+1 as the return on the value-weighted portfolio

of all index constituent firms included in our sample at time t.

Tables 4 and 5 report the regression results for S&P 100 and S&P 500 firms. The

results are consistent with the preceding evidence. For the pooled regressions, the Wald

tests of the joint hypothesis that α = 0 and γ = 0.5 do not reject our model (p-values

between 0.437 and 0.841), whereas the γ estimates are at least moderately significant

at horizons of three (six) months or longer for S&P 100 (S&P 500) firms.

Accounting for firm fixed effects, the significance of the γ estimate becomes more

pronounced even at the shorter horizons. For S&P 100 firms, we find p-values of

0.043 at the one-month horizon, 0.021 at the three-month horizon, and less than 0.01

for horizons of six, 12, and 24 months. Similarly, we find p-values of 0.073 at the one-

month horizon, 0.019 at the three-month horizon, and less than 0.01 for horizons of six,

12, and 24 months for S&P 500 firms. We also find, however, that the value-weighted

sum of firm fixed effects is statistically different from zero. This is the clearest violation

of the predictions of the theory, though we note that the estimates are fairly small in

economic terms (and we will see below that the model performs well when we drop

firm fixed effects entirely, as we do in our out-of-sample analysis).12

We have also run these regressions on subsamples of the data. Figure 7 plots the

estimated coefficients β and γ using successive yearly and three-yearly subsamples over

our sample period, and shows that our results are not driven by any one subperiod. It

also illustrates the point that the cross-sectional coefficient γ is easier to estimate, in

a statistical sense, than the ‘market’ coefficient β, because it exploits the information

in the entire cross-section of stocks.

4 Risk premia and stock characteristics

The results of the previous section show that the model performs well in forecasting

stock returns. Nonetheless, we would like to know whether there is return-relevant

12Moreover, the fixed effects are not statistically significant if we use portfolios sorted on SVIX2i,t

as test assets: see Tables IA.1, IA.2, IA.3 and IA.4 in the Internet Appendix.

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information in other firm characteristics that is not captured by our predictor variables

(see, e.g., Fama and French, 1993; Carhart, 1997; Lewellen, 2015).

As a preliminary check, Figure 8 shows that average realized excess returns line up

fairly well with our cross-sectional excess return predictor, 0.5(SVIX2i,t−SVIX

2

t ), for

characteristic-sorted portfolios. The return predictor for a portfolio is calculated by

averaging over its constituent stocks. Unless otherwise noted, we work with S&P 500

stocks and at an annual horizon throughout this section.

We test formally whether our framework is able to explain differences in risk premia

associated with the various characteristics in two ways: we run a horse-race between our

predictor variables and the characteristics in panel regressions at the individual stock

level; and we re-run the regressions of the previous section using portfolios double-

sorted on characteristics and on SVIX2i,,t as test assets.

Consider, first, the horse-race regressions. Table 6 reports the results for excess

returns. The first column shows the estimated coefficients in a regression of realized

excess returns onto characteristics; size and book-to-market are individually statisti-

cally significant, and we can reject the joint hypothesis that the coefficients on all

characteristics are zero. The second column shows that SVIX2t and SVIX2

i,t−SVIX2

t

drive out the characteristics. We do not reject the joint hypothesis that the coefficients

on the characteristics are all zero while those on the volatility measures are equal to

their theoretical values of 1 and 0.5; and adjusted R2 increases from 1.9% to 5.3% when

our predictor variables are added.

The corresponding results for returns in excess of the market are shown in Table 7,

and also support the theory. We do not find a statistically significant relationship

between the characteristics and realized returns in excess of the market (consistent

with the findings of Nagel (2005), who documents limited cross-sectional variation in

returns on S&P 500 stocks sorted on book-to-market, for example), but SVIX2i,t−SVIX

2

t

is statistically significant, and we do not reject the joint hypothesis that it enters with

a coefficient of 0.5 while the coefficients on all characteristics are zero; and adjusted

R2 increases from 1.0% to 4.0%.

The next columns of Tables 6 and 7 address the relationships between expected

excess returns and characteristics, with expected excess returns calculated in two ways:

using the coefficients estimated in regressions (18) or (20), and using the theory-implied

coefficients given in equations (16) or (17). The characteristics capture a sizeable

19

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fraction of the variation in theory-implied expected excess returns (R2 = 30.5%) and

theory-implied expected returns in excess of the market (R2 = 37.8%). In both cases

there is a significantly positive relationship between expected returns and beta and

a significantly negative relationship between expected returns and size, but the other

characteristics do not exhibit a statistically significant relationship to expected returns.

When we calculate expected returns using the estimated coefficients from (18) and (20)

rather than the theoretical values, the point estimates of the regression coefficients for

the characteristics are similar but are estimated less precisely, so are not significantly

different from zero.

The last two columns of the tables show that there is little evidence of a system-

atic relationship between unexpected (that is, realized minus expected) returns and

characteristics.

For our second test, we sort stocks into quintile portfolios based on their beta, size,

book/market, or momentum, and then within each characteristic portfolio we sort firms

into quintile portfolios based on SVIX2i,t. We run regressions (20) and (21) using the

5×5 portfolios as test assets, and calculate portfolio-level expected returns in excess of

the market as the equal-weighted average of the constituent stocks’ expected returns in

excess of the market. The results are shown in Table 8. Our model is never rejected. In

the specification that is least favorable to our theoretical predictions—the fixed-effects

regression with size-sorted portfolios—we find a p-value of 0.07 for the joint hypothesis

test; all other p-values are above 0.2, and the estimates of γ are close to 0.5. The

corresponding results for excess returns are in the Internet Appendix, Table IA.5. We

find similar results when we conduct the double sort in the opposite direction, first

sorting on SVIX2i,t and then on the other characteristic: see Tables IA.6 and IA.7.

We also conduct a principal components analysis to explore the factor structure in

unexpected returns, using the balanced panel of S&P 500 firms with full time-series

coverage. We consider three alternative definitions of unexpected returns: the resid-

uals computed using the pooled regressions, as in equation (20); residuals computed

using the panel regressions with fixed effects, as in equation (21); and residuals com-

puted using the model with coefficients constrained by theory, as in equation (16).

Encouragingly, all three lead to very similar results.

Figure 9 plots the time series of the first four principal components, which together

explain around 50% of the residual variance. It may be worth emphasizing that the

20

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presence of a strong factor structure in unexpected returns—had we found one—would

not necessarily constitute evidence against our approach: for example, in an economy

in which the APT held and stocks loaded on a single factor, there would be a strong

factor structure of unexpected returns, with the first principal component reflecting

unexpected shocks to the single factor. (We thank Stefan Nagel for pointing this out

to us.) It would be more problematic, however, if the factors shown in Figure 9 were

forecastable. Three of the four PCs appear to be related to extreme market episodes

whose evolution was, plausibly, hard to predict. PC1 is positive during the dotcom

boom, negative during the dotcom bust, and roughly zero at other times. PC3 is

negative during the crash of 2008–9, and roughly zero at other times. PC4 appears

to be related to the dotcom episode, like PC1: it is negative around the turn of the

millennium and close to zero at other times. Thus (unsurprisingly) a forecasting model

that could successfully predict the evolution and bursting of the dotcom “bubble,” or

the timing of the subprime crisis, would improve the performance of our framework.

Perhaps most intriguing, PC2 stands out in that it does not resemble an indicator

function for a particular market episode.

Table IA.8 in the Internet Appendix provides further evidence on the relationship

between the PCs and the SVIX indices used in our model, by running time series

regressions of PC1 to PC4 onto SVIX2t , SVIX2

t , SVIX2t /SVIX2

t , and SVIX2t −SVIX2

t .

(The explanatory variables are contemporaneous, so these should not be interpreted

as forecasting regressions.) For PC1, which explains around 25% of the variation in

unexpected returns, we find the highest R2s (around 0.11 to 0.15) when we use the

approximate correlation measure SVIX2t /SVIX2

t as explanatory variable. We have also

conducted the PCA on the residuals of SVIXi,t-sorted portfolio returns, since this allows

us to keep firms with less than full time-series coverage, with similar results: see Table

IA.9 and Figure IA.6.

5 Out-of-sample analysis

The formulas (16) and (17) have no free parameters, so it is reasonable to hope that

they may be well suited to out-of-sample forecasting. In this section, we show that they

are. This fact is particularly striking given the substantial variability of the forecasts

both in the time series and in the cross-section. The former point is consistent with

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Martin (2017); the latter is new to this paper. It is illustrated in Figure 10, which

plots the evolution of the cross-sectional differences in one-year expected excess returns

generated by our model.

5.1 Statistical forecast accuracy

We compare the performance of the formulas (16) and (17) to various competitor

forecasting benchmarks using an out-of-sample R-squared measure along the lines of

Goyal and Welch (2008). We define

R2OS = 1−

∑i

∑t FE

2M,it∑

i

∑t FE

2B,it

,

where FEM,it and FEB,it denote the forecast errors for stock i at time t based on our

model and on a benchmark prediction, respectively. Our model outperforms a given

benchmark if the corresponding R2OS is positive.

What are the natural competitor benchmarks? One possibility is to give up on

trying to make differential predictions across stocks, and simply to use a forecast of

the expected return on the market as a forecast for each individual stock. We consider

various ways of doing so. We use the market’s historical average excess return as

an equity premium forecast, following Goyal and Welch (2008) and Campbell and

Thompson (2008), and we use the S&P 500 (S&P500t) and the CRSP value-weighted

index (CRSPt) as proxies for the market. We also use the risk-neutral variance of

the market, SVIX2t , to proxy for the equity premium, as suggested by Martin (2017).

Lastly, we consider a constant excess return forecast of 6% p.a., corresponding to long-

run estimates of the equity premium used in previous research.

More ambitious competitor models would seek to provide differential forecasts of

individual firm stock returns, as we do. Again, we consider several alternatives. One

natural thought is to use historical average of firms’ stock excess returns (RXi,t). An-

other is to estimate firms’ conditional CAPM betas from historical return data and

combine the beta estimates with the aforementioned market premium predictions. We

also consider firm-level risk-neutral variance (SVIX2i,t) as a competitor forecasting vari-

able, motivated by Kadan and Tang (2016), who show that under certain conditions

SVIX2i,t provides a lower bound on stock i’s risk premium.

The results for expected excess returns are shown in Panel A of Table 9. Our

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formula (17) outperforms all the above competitors at the 3-, 6-, 12-, and 24-month

horizons, and its relative performance (as measured by R2OS) almost invariably increases

with forecast horizon, at least up to the one-year horizon.13 At the one-year horizon,

R2OS ranges from 1.68% to 3.82% depending on the competitor benchmark, with the

exception of the historical average stock return RXi,t, which it outperforms by a wide

margin, with an R2OS above 27%. This dramatic outperformance reflects an advantage

of our approach: it does not rely on historical data. This is particularly important

for stocks with short return histories that may not be representative of future returns.

For example, at the peak of the dotcome bubble, young tech firms had extremely

high historical average returns over their short histories. In such cases, employing

the historical average as a predictor may lead to large forecast errors for subsequent

returns.

The results for expected returns in excess of the market are shown in Panel B

and are, if anything, even stronger. We adjust the conditional CAPM predictions

appropriately (by multiplying the equity premium by beta minus one); and we add a

‘random walk’ forecast of zero. In doing so, we focus on the cross-sectional dimension

of firms’ equity returns, net of (noisy) market return forecasts. The formula (16)

outperforms all the competitors at every horizon, and the outperformance increases

with forecast horizon up to one year. At the one-year horizon, R2OS is around 3%

relative to each of the benchmarks.

More surprisingly, our model is competitive with—and at horizons of six months or

more, typically outperforms—a range of predictions based on in-sample information.

The first three lines of Panel A of Table 10 compare the performance of the excess-return

formula (17) to the in-sample average equity premium and the in-sample average excess

return on a stock (each of which makes the same forecast for every stock’s return); and

to estimated beta multiplied by the in-sample equity premium (which does differentiate

across stocks). In each case, R2OS is increasing with forecast horizon up to one year

and is positive at horizons of three, six, 12, and 24 months.

The next five lines compare the model forecasts to in-sample predictions based

on firm characteristics: more precisely, to the fitted values from pooled univariate

regressions of excess returns onto conditional betas, onto (log) size, onto book-to-

13The R2OS results are based on expected excess returns defined as EtRi,t+1−Rf,t+1, i.e. we multiply

the left and the right side of equations (16) and (17) by Rf,t+1.

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market ratios, or onto the stock’s past return. The formula outperforms each of the

characteristics at horizons of six and twelve months, and is competitive with the model

that knows the in-sample multivariate relationship between expected returns and all

four characteristics.

Remarkably, the model performs even better for returns in excess of the market.

The results are shown in Panel B of Table 10. The formula (16) outperforms the

univariate characteristics-based competitors at all horizons; it even beats the in-sample

multivariate model at horizons from 1 month to 1 year.

5.2 Economic value of model forecasts

To assess whether conditioning on stock return forecasts from our model generates

substantial economic value for investors, we compare the performance of a portfolio

with weights determined by model forecasts to a value-weighted portfolio and to an

equally-weighted portfolio. The value-weighted portfolio is a natural benchmark, while

previous research has shown that the equally-weighted portfolio has attractive proper-

ties (DeMiguel et al., 2009).

We have shown that our framework successfully forecasts expected excess returns

out of sample. It therefore supplies one of the two key ingredients for mean-variance

analysis—indeed, it supplies the ingredient that is traditionally viewed as harder to

estimate. We are currently working on combining the risk premium forecasts that

emerge from option prices, as here, with real-time estimates of the covariance matrix

based on historical price data, but this exercise is beyond the scope of the present

paper. For now, we therefore explore a trading strategy that only requires expected

returns as a signal for investment decisions.

More specifically, we follow Asness et al. (2013) in constructing portfolios based on

the ranks of firms’ expected returns by setting the portfolio weight of firm i for the

period from t to t+ 1 to be

wXSi,t =rank[EtRi,t+1]

θ∑i rank[EtRi,t+1]θ

. (22)

As θ ≥ 0 increases, the strategy responds increasingly aggressively to the expected

return signal. For θ = 0, the strategy corresponds to the equally-weighted portfolio

benchmark. We set θ = 2 in our baseline empirical analysis (and report results for

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θ = 1 in Tables IA.10 and IA.11).14

To evaluate the portfolio relative to the benchmarks, we compute returns, sample

moments, Sharpe ratios, and the performance fee as defined by Fleming et al. (2001).

For a given relative risk aversion ρ, the performance fee (Φ) quantifies the premium that

a risk-averse investor would be willing to pay to switch from the benchmark investment

(B) to the portfolio conditioning on the forecasts from our model (M). Specifically,

Φ is computed as a fraction of initial wealth (W0) such that two competing portfolio

strategies achieve equal average utility. Denoting the gross portfolio return of portfolio

k ∈ {B,M} by Rk,t+1, we compute the average realized utility, U ({Rk,t+1}), as

U ({Rk,t+1}) = W0

(T−1∑t=0

Rk,t+1 −ρ

2(1 + ρ)R2k,t+1

)and estimate the performance fee as the value Φ that satisfies

U ({RM,t+1 − Φ}) = U ({RB,t+1}) .

We start by considering an investor who rebalances her portfolio at the end of

every month. She may either invest in the market by choosing the value-weighted

portfolio or the equally-weighted portfolio, or use the model forecasts to determine the

portfolio weights according to equation (22) where we set θ = 2. Table 11 compares

the performance of these three alternatives. Different columns represent the horizon

of SVIX used to forecast returns; independent of this horizon, we update the portfolio

weights monthly.

The model-based portfolios have attractive Sharpe ratios and skewness, and as a

result investors would be willing to pay a sizeable fee to switch from the benchmark

to the model portfolios. The estimated fee, Φ, depends on the investor’s relative risk

aversion: setting ρ between one and ten, we find that the annual performance fee is

in the range of 2.35% to 5.75%. When we compare the model portfolio to the equal-

weighted portfolio, the estimates of Φ remain positive but are smaller, ranging from

0.07% to 2.50% per year.

Our approach allows the investor to update her expectations about each firm in

real time. Table IA.12, in the Internet Appendix, reports results when the investor is

14For 500 stocks, an equal-weighted strategy allocates a 0.2% weight to each asset in the portfolio;the maximum weight assigned to a single stock is 0.399% for θ = 1 and 0.598% for θ = 2.

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allowed to rebalance her portfolio at the end of every day rather than every month (for

the full sample of S&P 500 stocks); Tables IA.13 and IA.14 show that the utility gains

from using our model forecasts are particularly large among small and value stocks.

Figure 11 summarizes these results by plotting the cumulative returns on various model

portfolios, on the value- and equal-weighted index, and on cash. Figures IA.7–IA.10

show bootstrapped distributions of performance fees Φ at monthly and daily horizons;

and in different regions of the size/value universe.

6 Conclusions

This paper has presented new theoretical and empirical results on the cross-section of

expected stock returns. We would like to think that our approach to this classic topic

is idiosyncratic in more than one sense.

In sharp contrast with the factor model approach to the cross-section—which has

both the advantage and the disadvantage of imposing almost no structure, and therefore

says ex ante little about the anticipated signs, and nothing about the sizes, of coefficient

estimates—we make specific predictions both for the signs and sizes of coefficients, and

test these numerical predictions in the data. In this dimension, a better comparison is

with the CAPM, which makes the quantitative prediction that the slope of the security

market line should equal the market risk premium. But (setting aside the fact that it

makes no prediction for the market risk premium) even the CAPM requires betas to

be estimated if this prediction is to be tested. At times when markets are turbulent, it

is far from clear that historical betas provide robust measures of the idealized forward-

looking betas called for by the theory; and if the goal is to forecast returns over, say, a

one-year horizon, one cannot respond to this critique by taking refuge in the last five

minutes of high-frequency data. In contrast, our predictive variables, which are based

on option prices, are observable in real time and inherently forward-looking.

Our approach performs well in and out of sample, particularly over six-, 12-, and

24-month horizons. The model does a good job of accounting for realized returns

on portfolios sorted on characteristics (beta, size, book-to-market, and past returns)

known to be problematic for previous generations of asset-pricing models. When we run

stock-level panel regressions of realized returns onto characteristics and our volatility

predictor variables, our volatility variables drive out the characteristics and are them-

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selves statistically significant; and we do not reject the hypothesis that the associated

coefficients take the values predicted by the theory.

As the coefficients in the formula for the expected return on a stock are theoretically

motivated, we need only observe the market prices of certain options to implement the

formula: no estimation is required. Our approach therefore avoids the critique of Goyal

and Welch (2008), and we show that it outperforms a range of competitor predictors out

of sample—even including competitors with knowledge of the in-sample relationship

between expected returns and characteristics. Finally, we use the forecasts to define

trading strategies, and show that the resulting strategies perform well.

Our real-time measure of the expected return on a stock has many potential ap-

plications in macroeconomics, asset pricing, and corporate finance: for example, we

are currently exploring the reaction of expected stock returns to macroeconomic and

firm-specific news announcements. But more generally, our approach generates con-

siderably more variation in expected returns, both over time and across stocks, than

does, say, the CAPM. This points toward a quantitatively and qualitatively new view

of risk premia.

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Appendix

A A measure of correlation

This section shows that the ratio SVIX2t /SVIX

2

t can be interpreted as an approximate

measure of average risk-neutral correlation between stocks. Note first that

var∗t Rm,t+1−∑i

w2i,t var∗t Ri,t+1 =

∑i 6=j

wi,twj,t corr∗t (Ri,t+1, Rj,t+1)√

var∗t Ri,t+1 var∗t Rj,t+1,

so we can define a measure of average correlation, ρt, as

ρt =var∗t Rm,t+1 −

∑iw

2i,t var∗t Ri,t+1∑

i 6=j wi,twj,t√

var∗t Ri,t+1 var∗t Rj,t+1

.

Now, we have

ρt ≈var∗t Rm,t+1∑

iw2i,t var∗t Ri,t+1 +

∑i 6=j wi,twj,t

√var∗t Ri,t+1 var∗t Rj,t+1

=var∗t Rm,t+1(∑

iwi,t√

var∗t Ri,t+1

)2 .This last expression features the square of average stock volatility, rather than average

stock variance, in the denominator, but we can approximate(∑

iwi,t√

var∗t Ri,t+1

)2 ≈∑iwi,t var∗t Ri,t+1. (The approximation neglects a Jensen’s inequality term: the left-

hand side is strictly smaller than the right-hand side.) This leads us to the correlation

measure

ρt ≈var∗t Rm,t+1∑iwi,t var∗t Ri,t+1

=SVIX2

t

SVIX2

t

. (A.1)

B Bootstrap procedure

Our empirical analysis uses a large set of panel data, in which residuals may be corre-

lated across firms and across time. Petersen (2009) provides an extensive discussion of

how such cross-sectional and time-series dependencies in panel data may bias standard

errors in OLS regressions and suggests using two-way clustered standard errors. In a

further analysis, he finds that standard errors obtained from a bootstrap procedure

based on firm clusters are identical to the two-way clustered standard errors in his

panel data. We choose to work with bootstrap standard errors because this is the

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more conservative approach in our setup for two reasons. First, our monthly data

generates overlapping observations at return horizons exceeding one month. Second,

our data is characterized by high but less than perfect coverage of the cross-section of

index constituent firms, due to limited availability of option data.

To alleviate biases in standard errors that arise from applying asymptotic theory

to finite samples, we use a non-parametric bootstrap procedure based on resampling.

More specifically, because our data is characterized by time-series dependence, we use

an overlapping block resampling scheme (originally proposed by Kuensch, 1989) to

handle serial correlation and heteroskedasticity; in that block bootstrap procedure, we

also take cross-sectional dependencies into account. Using a large number of bootstrap

samples, we estimate the bootstrap covariance matrix and estimate Wald statistics, as

we describe in more detail in Section B.1 below. In Section B.2, we provide simulation

evidence on the finite-sample properties of the block bootstrap procedure; the detailed

results are in the Internet Appendix.

B.1 Implementation of the block bootstrap procedure

We first describe the details of the block bootstrap procedure that we apply for pooled

regressions of returns in excess of the market. Second, we discuss the adjustments to the

procedure in regressions of excess returns (instead of excess market returns) and, third,

the adjustments to the procedure when using firm fixed effects regressions (instead

of pooled regressions). Fourth, we discuss the adjustments for portfolio regressions

(compared to regressions on the individual firm level), and, finally, how we use the

framework to generate a bootstrap distribution of the performance fees used to assess

economic value of our model forecasts in trading strategies.

Pooled regressions of returns in excess of the market. Use a block bootstrap

approach to generate b = 1, ..., B bootstrap samples by resampling from the actual

panel data, as suggested by Kuensch (1989). From the actual data, we need dates,

firm identifiers, firms’ stock returns in excess of the risk-free rate, firms’ risk-neutral

variances (SVIX2i,t), and firms’ market capitalizations.

1. We generate B = 1, 000 bootstrap samples of panel data, where the number of

time periods in each sample matches the number of time periods in the actual

data. More specifically, we generate a bootstrap sample b as follows:

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(a) Start the resampling procedure by randomly drawing a block of time-length

T , i.e. corresponding to the return prediction horizon and the maturity of

the options used to compute the SV IX-quantities.15 From the block drawn,

randomly select a subset of firms.16

(b) Draw further (overlapping) blocks, with replacement, until the bootstrap

sample has the same number of time periods as the actual data.

(c) For every point in time in the bootstrap sample b, determine the firms’

market weights and compute the value-weighted average of individual stocks’

risk-neutral variance, i.e. SVIX2

t =∑

iwi,t SVIX2i,t, the market return as the

return on the value-weighted portfolio, and the stocks’ returns in excess of

the market.

2. For each bootstrap sample, run the pooled regression of returns in excess of the

market onto risk-neutral excess stock variance,

Ri,t+1 −Rm,t+1

Rf,t+1

= α + γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

and collect the B = 1, 000 bootstrap estimates of α and γ.

3. Using the B = 1, 000 bootstrap estimates of α and γ, compute the bootstrap

covariance matrix of α and γ. Using this bootstrap covariance matrix, we com-

pute Wald statistics for hypothesis tests.17 Building on the asymptotic refine-

15In time-series bootstraps, it is possible to implement automated procedures that determine theblock-length based on the properties of the time- series (e.g., Politis and White, 2004; Patton et al.,2009). These procedures are not implementable in our panel data setup as different firm time-seriesmay suggest different block lengths but we need to choose a single block length across all firms toaccount for the cross-sectional dependencies in the data across time. For instance, for T = 12 months

we find that applying such a procedure for different firm time-series of SVIX2i,t−SVIX

2

t would suggestblock lengths between approximately 8 and 24 months. We repeat our bootstrap procedure with theseblock lengths 8 and 24 months, instead of 12 months, and find that our conclusions remain unchanged.We therefore set the block-length equal to return horizon T to account for overlapping observationsand follow the suggestion of Lahiri (1999) to keep the block length fixed and to allow for overlaps inthe blocks.

16The idea is to account for the empirical reality that options data may not be available for all firms.For the large number of bootstrap samples B = 1, 000 that we use, the results of randomly selectinga subset of firms or including all firms that are available in a drawn block leads to identical results.Conceptually, our approach is similar to the bootstrap using firm clusters described by Petersen (2009)in his footnote 12.

17We prefer to compute the Wald statistic based on the bootstrap covariance matrix rather than to

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ment achieved from bootstrapping the covariance matrix, we use the Wald tests’

asymptotic distribution to compute the p-values; we discuss the finite-sample

properties of our bootstrap procedure below in Section B.2.

Pooled regressions of excess returns. The bootstrap procedure for pooled re-

gressions of excess returns is essentially the same as the one described for returns in

excess of the market above. The only modifications are:

• In step 1, also include the risk-neutral market variance (SVIX2t ) in the resampling

procedure.

• In step 2, run the regression of excess returns on SVIX2t and SVIX2

i,t−SVIX2

t ,

and collect the B = 1, 000 bootstrap estimates of α, β, and γ.

• In step 3, compute the bootstrap covariance matrix for α, β, and γ and use it to

compute standard errors and to conduct hypothesis tests.

Regressions with firm fixed effects. For the bootstraps of the firm fixed effects

regressions we adjust the procedure for the pooled regressions described above as fol-

lows:

• In step 2, run the regression with firm fixed effects αi (instead of the intercept

α) and

– compute the value-weighted sum of firm fixed effects at every date in every

bootstrap sample, i.e. αt =∑

iwi,tαi

– in each bootstrap sample, compute α as the time-series average of αt

– collect the B = 1, 000 estimates of α (instead of intercept α)

• In step 3, compute the bootstrap covariance matrix with α (instead of intercept

α) and use it to compute standard errors and to conduct hypothesis tests.

bootstrap the Wald statistic because our approach explicitly takes cross-sectional dependencies as wellas overlapping observations and other time-dependencies into account. Qualitatively, our results arevery similar when we bootstrap Wald statistics that are computed using a double-clustered covariancematrix as suggested by Petersen (2009). The quantitative bootstrap results of the Wald tests canbe quite different when using a non-clustered covariance matrix, but we would still not reject themodel. As a further sanity check, we also verified that the p-values of bootstrapped likelihood ratiotest statistics are identical to those of the bootstrapped Wald statistics computed from non-clusteredcovariance matrices.

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Portfolio regressions. The bootstraps for pooled and fixed effects regressions using

excess returns and excess market returns of portfolios follow the corresponding firm-

level procedures described above. The only difference is that in step 1 (a), we do not

resample in the cross-section, i.e. we use all portfolios; the reason is that unlike the

firm level data where we have an unbalanced panel, we do have a balanced panel of

portfolio data.

Performance fees. We use the resampling procedure described in step 1. above

to generate 1,000 bootstrap samples. In each bootstrap sample, we implement the

out-of-sample trading strategy using model forecasts to construct rank-weighted port-

folios. We then compare the performance of the model portfolios to value- and equally-

weighted portfolios in each sample, thereby obtaining the bootstrap distribution of the

performance fee.

B.2 Finite sample properties of the block bootstrap procedure

To provide evidence for the reliability of our bootstrap procedure in finite samples,

we conduct a simulation study. We simulate S samples on which we impose the null

hypothesis and within each sample we repeat the bootstrap procedure from Section B.1

above with B iterations. We then, first, compare the empirical quantiles of the Wald

statistic in the simulated data to the quantiles of χ2-distribution, i.e. the Wald statis-

tic’s asymptotic distribution. These results suggest that our procedure, using the

bootstrap covariance matrix to compute the Wald statistic and then using the asymp-

totic distribution to infer its p-value, is reasonable. Second, we compare the rejection

frequency for the null hypothesis in the simulated data (on which we imposed the null

hypothesis) to the nominal size of the test, and these results provide further support

for our empirical approach.

Given the enormous computational demand of this exercise with an additional S×Bbootstrap samples to be generated and evaluated, we focus on the pooled regressions

of S&P 100 firms’ returns in excess of the market. We simulate data under the null

hypothesis by imposing α = 0 and γ = 0.5 and drawing blocks of innovations from

the regression residuals (from the specification in Panel A of Table 4). The block

resampling scheme follows the approach described above in Section B.1 and again

serves to account for cross-sectional and time-series dependencies. We start by setting

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the number of simulations S = 200 and the number of bootstrap iterations to B = 99,

thereby following the choice of Piatti and Trojani (2014) in a similar double-bootstrap

exercise; we also show that the results are similar when we increase the number of

simulations to S = 400 and the number of bootstrap iterations to B = 198. Our

subsequent discussion is based on the results for the one-year horizon and we then

show that our conclusions are very similar for other horizons.

Empirical and asymptotic quantiles of the Wald statistic. Panel A in Fig-

ure IA.11 compares the empirical quantiles of the Wald statistic in the simulated data

to the quantiles of the Wald statistic’s asymptotic χ2-distribution. With the vertical

lines marking the 90%-, 95%-, and 99%-quantiles, the plot shows that the empiri-

cal quantiles are virtually identical to the quantiles of the χ2-distribution beyond the

95%-quantile; only in the very far tails of the distribution the critical values from the

empirical distribution exceed those from the chi-squared distribution. These results

suggest that our approach to, first, use the bootstrap covariance matrix to compute

the Wald statistic, and then, second, to use the asymptotic distribution to infer the

p-value of the Wald statistic, should work well.

Nominal size and empirical rejection frequencies. Panel B in Figure IA.11

compares the empirical rejection frequencies of our bootstrap approach when applied to

simulated data (on which we impose the null hypothesis) to the corresponding nominal

size of the test. That is, we compute the fraction of samples in which the bootstrap

procedure leads to a rejection of the hypothesis when using the nominal size given on

the x-axis. Similar as in Panel A, the dotted and dashed lines plot the 90%/10%-,

95%/5%-, and 99%/1%- quantiles to mark the economically interesting regions, where

we care about rejections. We find that empirical rejection frequencies are well aligned

with nominal size, in particular within these economically interesting regions, and that

differences in empirical rejections frequencies and nominal size should be too small to

lead to incorrect inference in our empirical analysis. To illustrate this, the big symbol

in the plot indicates the p-value of the Wald statistic that we obtain from our empirical

test of the model in the data; this p-value is 0.437 as reported in Panel A of Table 4.

These results suggest that we are very far away from making an inference error.

Using horizons shorter and longer than one year, Figure IA.12 shows that the empirical

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quantiles of the Wald statistic in the simulated data also line up well with quantiles of

the Wald statistic’s asymptotic χ2-distribution for horizons of three and six months.

For the shortest (longest) horizon of one (24) month(s), the empirical quantiles appear

somewhat too low (high) compared to the asymptotic quantiles. Nonetheless, the

comparison of empirical rejection frequencies in the simulated data to the nominal sizes

used in the tests in Figure IA.13 suggests that we are unlikely to make an inference error

at any horizon. All results are very similar when increasing the number of simulations

and bootstrap iterations to S = 400 and B = 198 as we show in Figure IA.14; overall

the alignment of empirical rejection frequencies in the simulated data with nominal

sizes used in the tests slightly improves when increasing S to 400 and B to 198.

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37

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Table 1: Sample data

This Table summarizes the data used in the empirical analysis. We search the OptionMetrics database for all firmsthat have been included in the S&P 100 or S&P 500 during the sample period from January 1996 to October 2014and obtain all available volatility surface data. We use this data to compute firms’ risk-neutral variances

(SVIX2

i,t

)for horizons of one, three, six, 12, and 24 months. Panel A summarizes the number of total observations, thenumber of unique days and unique firms in our sample, as well as the average number of firms for which optionsdata is available per day. For some econometric analysis, we also compile data subsets at a monthly frequency forfirms included in the S&P 100 (summarized in Panel B) and the S&P 500 (Panel C).

Panel A. Daily data

Horizon 30 days 91 days 182 days 365 days 730 days

Observations 2,106,711 2,106,711 2,106,711 2,106,711 2,106,711

Sample days 4,674 4,674 4,674 4,674 4,674

Sample firms 869 869 869 869 869

Average firms/day 451 451 451 451 451

Panel B. Monthly data for S&P 100 firms

Horizon 30 days 91 days 182 days 365 days 730 days

Observations 21,205 20,820 20,247 19,100 16,896

Sample months 224 222 219 213 201

Sample firms 177 176 176 171 167

Average firms/month 95 94 92 90 84

Panel C. Monthly data for S&P 500 firms

Horizon 30 days 91 days 182 days 365 days 730 days

Observations 102,198 100,252 97,340 91,585 80,631

Sample months 224 222 219 213 201

Sample firms 877 869 863 832 770

Average firms/month 456 452 444 430 401

38

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Table 2: Expected excess returns of S&P 100 firms

This Table presents results from regressing equity excess returns of S&P 100 firms on the risk-neutral variance ofthe market variance (SVIX2

t ) and the stock’s risk-neutral variance measured relative to stocks’ average risk-neutral

variance(

SVIX2i,t−SVIX

2

t

). The data is monthly from January 1996 to October 2014. The column labels indicate

the return horizons ranging from one month to two years. The return horizons match the maturities of the options

used to compute SVIX2t , SVIX2

i,t, and SVIX2

t . Panel A reports estimates of the pooled regression specified inequation (18), Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with firm fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept, β = 1, and γ = 0.5) and for tests whether β and γ are equal to zero. Forthe pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficientsare fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.073 0.035 -0.009 0.001 -0.006

(0.064) (0.074) (0.054) (0.067) (0.068)

β -0.001 1.070 2.244 1.956 1.990

(2.032) (2.263) (1.465) (1.404) (1.517)

γ 0.469 0.489 0.729 0.834 0.736

(0.346) (0.332) (0.340) (0.343) (0.267)

Pooled adj-R2 (%) 0.274 0.942 3.809 6.387 7.396

H0 : α = 0, β = 1, γ = 0.5 0.550 0.687 0.660 0.566 0.608

H0 : β = γ = 0 0.356 0.335 0.064 0.045 0.012

H0 : γ = 0.5 0.929 0.974 0.500 0.330 0.376

H0 : γ = 0 0.175 0.140 0.032 0.015 0.006

Theory adj-R2 (%) 0.099 0.625 2.509 3.896 4.830

Panel B. Firm fixed-effects regressions∑wiαi 0.089 0.051 0.010 0.018 0.003

(0.062) (0.071) (0.051) (0.064) (0.066)

β -0.085 0.947 2.091 1.793 1.876

(2.041) (2.277) (1.423) (1.325) (1.391)

γ 0.734 0.801 1.126 1.225 1.083

(0.392) (0.387) (0.370) (0.314) (0.273)

Panel adj-R2 (%) 1.211 4.771 11.861 20.003 27.455

H0 :∑i wiαi = 0, β = 1, γ = 0.5 0.233 0.363 0.274 0.111 0.184

H0 : β = γ = 0 0.128 0.103 0.008 0.000 0.000

H0 : γ = 0.5 0.551 0.436 0.091 0.021 0.033

H0 : γ = 0 0.061 0.038 0.002 0.000 0.000

39

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Table 3: Expected excess returns of S&P 500 firms

This Table presents results from regressing equity excess returns of S&P 500 firms on the risk-neutral variance ofthe market variance (SVIX2

t ) and the stock’s risk-neutral variance measured relative to stocks’ average risk-neutral

variance(

SVIX2i,t−SVIX

2

t

). The data is monthly from January 1996 to October 2014. The column labels indicate

the return horizons ranging from one month to two years. The return horizons match the maturities of the options

used to compute SVIX2t , SVIX2

i,t, and SVIX2

t . Panel A reports estimates of the pooled regression specified inequation (18), Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with firm fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept, β = 1, and γ = 0.5) and for tests whether β and γ are equal to zero. Forthe pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficientsare fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.057 0.019 -0.038 -0.021 -0.054

(0.074) (0.079) (0.059) (0.071) (0.076)

β 0.743 1.882 3.483 3.032 3.933

(2.311) (2.410) (1.569) (1.608) (1.792)

γ 0.214 0.305 0.463 0.512 0.324

(0.296) (0.287) (0.320) (0.318) (0.200)

Pooled adj-R2 (%) 0.096 0.767 3.218 4.423 5.989

H0 : α = 0, β = 1, γ = 0.5 0.267 0.242 0.169 0.184 0.015

H0 : β = γ = 0 0.770 0.553 0.071 0.092 0.036

H0 : γ = 0.5 0.333 0.497 0.908 0.971 0.377

H0 : γ = 0 0.470 0.287 0.148 0.108 0.105

Theory adj-R2 (%) -0.107 0.227 1.491 1.979 1.660

Panel B. Firm fixed-effects regressions∑wiαi 0.080 0.042 -0.008 0.012 -0.026

(0.072) (0.075) (0.055) (0.070) (0.079)

β 0.603 1.694 3.161 2.612 3.478

(2.298) (2.392) (1.475) (1.493) (1.681)

γ 0.491 0.634 0.892 0.938 0.665

(0.325) (0.331) (0.336) (0.308) (0.205)

Panel adj-R2 (%) 0.650 4.048 10.356 17.129 24.266

H0 :∑i wiαi = 0, β = 1, γ = 0.5 0.231 0.224 0.164 0.133 0.060

H0 : β = γ = 0 0.265 0.119 0.019 0.008 0.002

H0 : γ = 0.5 0.978 0.686 0.243 0.155 0.420

H0 : γ = 0 0.131 0.056 0.008 0.002 0.001

40

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Table 4: Expected returns in excess of the market of S&P 100 firms

This Table presents results from regressing equity returns in excess of the market on the stock’s risk-neutral

variance measured relative to stocks’ average risk-neutral variance(

SVIX2i,t−SVIX

2

t

)for S&P 100 firms. The

data is monthly from January 1996 to October 2014. The column labels indicate the return horizons ranging fromone month to two years. The return horizons match the maturities of the options used to compute SVIX2

i,t and

SVIX2

t . Panel A reports estimates of the pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with firm fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. For the pooledregressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficients are fixedat the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.008 0.008 0.005 0.007 0.010

(0.015) (0.014) (0.015) (0.016) (0.016)

γ 0.541 0.551 0.761 0.819 0.723

(0.345) (0.313) (0.328) (0.337) (0.270)

Pooled adj-R2 (%) 0.473 1.185 3.527 6.070 6.665

H0 : α = 0, γ = 0.5 0.841 0.832 0.609 0.437 0.439

H0 : γ = 0.5 0.906 0.871 0.427 0.344 0.409

H0 : γ = 0 0.118 0.079 0.020 0.015 0.007

Theory adj-R2 (%) 0.463 1.151 3.054 5.005 5.712

Panel B. Firm fixed-effects regressions∑i wiαi 0.026 0.024 0.023 0.022 0.020

(0.010) (0.009) (0.009) (0.009) (0.009)

γ 0.780 0.833 1.120 1.156 1.018

(0.385) (0.360) (0.348) (0.313) (0.286)

Panel adj-R2 (%) 1.097 4.013 9.896 16.866 24.071

H0 :∑i wiαi = 0, γ = 0.5 0.026 0.012 0.006 0.002 0.013

H0 : γ = 0.5 0.468 0.355 0.074 0.036 0.070

H0 : γ = 0 0.043 0.021 0.001 0.000 0.000

41

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Table 5: Expected returns in excess of the market of S&P 500 firms

This Table presents results from regressing equity returns in excess of the market on the stock’s risk-neutral

variance measured relative to stocks’ average risk-neutral variance(

SVIX2i,t−SVIX

2

t

)for S&P 500 firms. The

data is monthly from January 1996 to October 2014. The column labels indicate the return horizons ranging fromone month to two years. The return horizons match the maturities of the options used to compute SVIX2

i,t and

SVIX2

t . Panel A reports estimates of the pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with firm fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. For the pooledregressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficients are fixedat the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.016 0.016 0.013 0.014 0.019

(0.015) (0.015) (0.016) (0.019) (0.019)

γ 0.301 0.414 0.551 0.553 0.354

(0.285) (0.273) (0.306) (0.302) (0.200)

Pooled adj-R2 (%) 0.135 0.617 1.755 2.892 1.901

H0 : α = 0, γ = 0.5 0.489 0.560 0.630 0.600 0.596

H0 : γ = 0.5 0.486 0.752 0.869 0.862 0.467

H0 : γ = 0 0.291 0.129 0.072 0.068 0.077

Theory adj-R2 (%) 0.068 0.547 1.648 2.667 1.235

Panel B. Firm fixed-effects regressions∑i wiαi 0.036 0.034 0.033 0.033 0.033

(0.008) (0.007) (0.008) (0.008) (0.008)

γ 0.560 0.730 0.949 0.917 0.637

(0.313) (0.313) (0.319) (0.291) (0.199)

Panel adj-R2 (%) 0.398 3.015 7.320 12.637 17.479

H0 :∑i wiαi = 0, γ = 0.5 0.000 0.000 0.000 0.000 0.000

H0 : γ = 0.5 0.848 0.461 0.160 0.152 0.491

H0 : γ = 0 0.073 0.019 0.003 0.002 0.001

42

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Table 6: The relationship between realized, expected, and unexpected returns andcharacteristics

This Table presents results from regressing realized, expected, and unexpected equity excess returns (yi,t+1) on thefirm’s CAPM beta, log size, book-to-market, past return, risk-neutral market variance (SVIXt), and risk-neutral

stock variance measured relative to stocks’ average risk-neutral variance (SVIX2i,t−SVIX

2

t ):

yi,t+1 = a+ b1Betai,t + b2log(Sizei,t) + b3B/Mi,t + b4Ret(12,1)i,t + c0 SVIX2

t +c1

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

The data is monthly and covers S&P 500 firms from January 1996 to October 2014. The first two columns presentresults for realized returns, the middle two columns for expected returns, and the last two columns for unexpectedreturns. In columns labelled ‘theory’, we set the parameter values of our model forecast to the values impliedby theory (i.e. we use equation (17)); while in columns labelled ‘estimated’, we use parameter estimates of apooled regression (i.e. we use the estimates obtained from the regression specified in equation (18) and reportedin Table 3). The return horizon is one year. Values in parentheses are standard errors obtained from the blockbootstrap procedure described in Appendix B. The last four rows report adjusted-R2 and the p-values of Waldtests of joint parameter significance, testing (i) whether all bi-estimates are zero, (ii) whether all bi-estimates arezero, c0 = 1, and c1 = 0.5, (iii) whether all non-constant coefficients are jointly zero.

Realized returns Expected returns Unexpected returns

estimated theory estimated theory

const 0.721 0.452 0.259 0.164 0.462 0.557

(0.341) (0.320) (0.133) (0.035) (0.332) (0.331)

Betai,t 0.038 -0.048 0.082 0.097 -0.044 -0.059

(0.068) (0.068) (0.064) (0.018) (0.046) (0.072)

log(Sizei,t) -0.030 -0.019 -0.010 -0.009 -0.019 -0.021

(0.014) (0.013) (0.007) (0.002) (0.013) (0.013)

B/Mi,t 0.071 0.068 0.003 0.001 0.068 0.069

(0.034) (0.038) (0.010) (0.006) (0.038) (0.037)

Ret(12,1)i,t -0.049 -0.005 -0.046 -0.026 -0.003 -0.023

(0.063) (0.054) (0.042) (0.015) (0.050) (0.058)

SVIX2t 2.792

(1.472)

SVIX2i,t−SVIX

2

t 0.511

(0.357)

adj-R2 (%) 1.924 5.265 17.277 30.482 0.973 1.197

H0 : bi = 0 0.003 0.201 0.702 0.000 0.187 0.092

H0 : bi = 0, c0 = 1, c1 = 0.5 0.143

H0 : bi = 0, c0 = 0, c1 = 0 0.001

43

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Table 7: The relationship between realized, expected, and unexpected excess marketreturns and characteristics

This Table presents results from regressing realized, expected, or unexpected equity returns in excess of the market(yi,t+1) on the firm’s CAPM beta, log size, book-to-market, past return, and risk-neutral stock variance measured

relative to stocks’ average risk-neutral variance, SVIX2i,t−SVIX

2

t :

yi,t+1 = a+ b1Betai,t + b2 log(Sizei,t) + b3B/Mi,t + b4Ret(12,1)i,t + c

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

The data is monthly and covers S&P 500 firms from January 1996 to October 2014. The first two columns presentresults for realized returns, the middle two columns for expected returns, and the last two columns for unexpectedreturns. In columns labelled ‘theory,’ we set the parameter values of our model forecast to the values implied byequation (16); in columns labelled ‘estimated,’ we use parameter estimates of a pooled regression (i.e. we use theestimates obtained from the regression specified in equation (20) and reported in Table 5). The return horizonis one year. Values in parentheses are standard errors obtained from the block bootstrap procedure describedin Appendix B. The last three rows report the regression’s adjusted-R2 and the p-values of Wald tests on jointparameter significance, testing (i) whether all bi-estimates are zero, (ii) whether all bi-estimates are zero and c = 0.5,(iii) whether all non-constant coefficients are jointly zero.

Realized returns Expected returns Unexpected returns

estimated theory estimated theory

const 0.429 0.277 0.131 0.107 0.298 0.321

(0.371) (0.377) (0.073) (0.027) (0.365) (0.359)

Betai,t 0.016 -0.131 0.113 0.105 -0.097 -0.088

(0.075) (0.062) (0.066) (0.016) (0.046) (0.078)

log(Sizei,t) -0.018 -0.006 -0.009 -0.009 -0.009 -0.010

(0.014) (0.015) (0.006) (0.002) (0.015) (0.013)

B/Mi,t 0.032 0.031 0.001 0.001 0.032 0.032

(0.025) (0.027) (0.006) (0.005) (0.026) (0.026)

Ret(12,1)i,t -0.051 -0.029 -0.017 -0.015 -0.034 -0.035

(0.041) (0.041) (0.018) (0.010) (0.039) (0.040)

SVIX2i,t−SVIX

2

t 0.705

(0.308)

adj-R2 (%) 1.031 3.969 37.766 37.766 1.051 0.974

H0 : bi = 0 0.347 0.153 0.435 0.000 0.157 0.619

H0 : bi = 0, c = 0.5 0.234

H0 : bi = 0, c = 0 0.018

44

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Table 8: Excess market returns of characteristics/SVIXi,t double-sorted portfolios

This Table presents results from regressing portfolio equity returns in excess of the market on the portfolio stock’s

risk-neutral variance measured relative to stocks’ average risk-neutral variance, SVIX2i,t−SVIX

2

t . The data ismonthly from January 1996 to October 2014. At the end of each month, we sort S&P 500 firms into 5x5-doublesorted portfolios based on firm characteristics and SVIXi,t. We first assign firms to quintile portfolios basedon their CAPM beta, size, book-to-market, or momentum. In the second step, we sort stocks within each ofthe characteristics portfolios into SVIXi,t-quintiles, providing us with a total of 25 conditionally double-sortedportfolios. The one-year horizon of the portfolio returns matches the 365 day-maturity of the options used to

compute SVIX2i,t and SVIX

2

t . Panel A reports estimates of the pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with portfolio fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. For the pooledregressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficients are fixedat the values predicted by our theory.

Beta Size B/M Mom

Panel A. Pooled regressions

α 0.015 0.013 0.015 0.014

(0.019) (0.020) (0.020) (0.019)

γ 0.495 0.572 0.502 0.559

(0.311) (0.323) (0.327) (0.319)

Pooled adj-R2 (%) 8.391 9.908 8.098 10.245

H0 : α = 0, γ = 0.5 0.635 0.593 0.635 0.613

H0 : γ = 0.5 0.987 0.823 0.996 0.890

H0 : γ = 0 0.112 0.076 0.125 0.088

Theory adj-R2 (%) 7.598 8.995 7.232 8.555

Panel B. Portfolio fixed-effects regressions∑i wiαi 0.015 0.008 0.014 0.019

(0.017) (0.005) (0.016) (0.017)

γ 0.794 0.941 0.711 0.864

(0.490) (0.529) (0.507) (0.491)

Panel adj-R2 (%) 13.010 16.419 12.679 15.020

H0 :∑i wiαi = 0, γ = 0.5 0.439 0.070 0.479 0.212

H0 : γ = 0.5 0.549 0.405 0.677 0.459

H0 : γ = 0 0.106 0.075 0.161 0.079

45

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Table 9: Out-of-sample forecast accuracy

This Table presents results on the out-of-sample accuracy of our model relative to benchmark predictions. To

compare the forecast accuracy of the model to that of the benchmarks, we compute an out-of-sample R-squared,

defined as

R2OS = 1−

∑i

∑t FE

2M∑

i

∑t FE

2B

,

where FEM and FEB denoted the forecast errors from our model and a benchmark prediction, respectively. Panel

A evaluates forecasts of expected equity excess returns, as given in equation (17), and Panel B evaluates forecasts

of expected equity returns in excess of the market return, as given in equation (16). The data is monthly and

covers S&P 500 stocks from January 1996 to October 2014. The column labels indicate the return horizons ranging

from one month to two years. The return horizons match the maturities of the options used to compute SVIX2t ,

SVIX2i,t, and SVIX

2

t . For Panel A, the benchmark forecasts are the risk-neutral market variance (SVIX2t ), the

time-t historical average excess returns of the S&P 500 (S&P500t) and the CRSP value-weighted index (CRSPt), a

constant prediction of 6% p.a., the stock’s risk-neutral variance (SVIX2i,t), the time-t historical average of the firms’

stock excess returns (RXi,t), and conditional CAPM implied predictions, where we estimate the CAPM betas from

historical return data. For Panel B, we use SVIX2i,t, a random walk (i.e., zero return forecast), and the conditional

CAPM as benchmarks.

Panel A. Expected excess returns

Horizon 30 days 91 days 182 days 365 days 730 days

SVIX2t 0.09 0.57 1.77 3.08 2.77

S&P500t 0.09 0.79 2.56 3.82 4.46

CRSPt -0.09 0.24 1.43 1.70 0.88

6% p.a. -0.01 0.46 1.84 2.54 2.06

SVIX2i,t 0.95 1.87 1.55 2.17 7.64

RXi,t 1.40 4.97 11.79 27.10 56.67

β̂i,t × S&P500t 0.09 0.79 2.54 3.76 4.72

β̂i,t × CRSPt -0.06 0.28 1.46 1.68 1.61

β̂i,t× SVIX2t 0.04 0.46 1.58 2.87 2.91

β̂i,t× 6% p.a. 0.00 0.47 1.84 2.48 2.58

Panel B. Expected returns in excess of the market

Horizon 30 days 91 days 182 days 365 days 730 days

Random walk 0.16 0.76 1.92 3.07 1.99

(β̂i,t − 1)× S&P500t 0.18 0.80 1.98 3.10 2.17

(β̂i,t − 1)× CRSPt 0.21 0.89 2.14 3.35 2.83

(β̂i,t − 1)× SVIX2t 0.11 0.62 1.68 2.80 2.01

(β̂i,t − 1)× 6% p.a. 0.19 0.83 2.04 3.19 2.49

46

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Table 10: Model out-of-sample forecasts vs in-sample benchmark predictions

This Table presents results on the out-of-sample accuracy of our model relative to benchmark predictions that

also include in-sample information on returns and/or firm characteristics. To compare the forecast accuracy of the

model to that of the benchmarks, we compute an out-of-sample R-squared, defined as

R2OS = 1−

∑i

∑t FE

2M∑

i

∑t FE

2B

,

where FEM and FEB denoted the forecast errors from our model and a benchmark prediction, respectively. Panel

A evaluates forecasts of expected equity excess returns, as given in equation (17), and Panel B evaluates forecasts

of expected equity returns in excess of the market return, as given in equation (16). The data is monthly and covers

S&P 500 stocks from January 1996 to October 2014. The column labels indicate the return horizons ranging from

one month to two years. The return horizons match the maturities of the options used to compute SVIX2t , SVIX2

i,t,

and SVIX2

t . For Panel A, the benchmark forecasts are the in-sample average market excess return, a conditional

CAPM forecast that uses the in-sample average market excess return as an estimate of the equity premium, the

in-sample average return across all stocks; and the fitted values of predictive in-sample regressions of stock returns

in excess of the market on CAPM betas, log market capitalization, book-to-market ratios, stock momentum, and

all four firm characteristics. For Panel B, we use analogous predictions based on returns in excess of the market.

Panel A. Expected excess returns

Horizon 30 days 91 days 182 days 365 days 730 days

in-sample avg mkt -0.05 0.31 1.52 1.90 1.42

in-sample avg all stocks -0.09 0.17 1.26 1.42 0.56

β̂i,t× in-sample avg mkt -0.03 0.34 1.54 1.87 2.04

Betai,t -0.09 0.16 1.22 1.30 0.56

log(Sizei,t) -0.19 -0.17 0.62 0.21 -1.34

B/Mi,t -0.18 -0.03 0.89 0.77 0.00

Ret(12,1)i,t -0.10 0.15 1.09 1.05 -0.76

All -0.25 -0.30 0.26 -0.53 -2.71

Panel B. Expected returns in excess of the market

Horizon 30 days 91 days 182 days 365 days 730 days

in-sample avg all stocks 0.11 0.58 1.60 2.48 0.95

(β̂i,t − 1)× in-sample avg mkt 0.20 0.86 2.11 3.29 2.63

Betai,t 0.11 0.58 1.60 2.45 0.95

log(Sizei,t) 0.05 0.39 1.27 1.90 0.12

B/Mi,t 0.07 0.50 1.47 2.31 0.88

Ret(12,1)i,t 0.10 0.56 1.47 2.05 0.03

All 0.03 0.34 1.11 1.46 -0.64

47

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Table 11: Portfolio performance with monthly rebalancing

This Table summarizes the performance of monthly rebalanced portfolios invested in S&P 500 stocks from January1996 to October 2014. We compare the performance of a portfolio based on model-implied expected excess returnsto the market benchmark (a value-weighted portfolio) and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy, and we set θ = 2. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio. The column labels indicate the variance horizon used in themodel forecast.

30 days 91 days 182 days 365 days 730 days

Portfolio performance based on model forecasts

Mean (%p.a.) 10.89 11.68 11.86 12.53 12.31

Sd (%p.a.) 24.54 24.60 24.65 24.62 24.63

Sharpe ratio (p.a.) 0.44 0.47 0.48 0.51 0.50

Skewness −0.12 −0.07 −0.07 −0.06 −0.07

Excess kurtosis 1.55 1.48 1.56 1.47 1.28

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.45 0.44 0.43 0.41 0.36

Skewness −0.61 −0.60 −0.59 −0.58 −0.54

Excess kurtosis 0.82 0.76 0.73 0.67 0.57

Performance fee with ρ = 1 (%p.a.) 3.10 3.92 4.26 5.19 5.75

Performance fee with ρ = 3 (%p.a.) 2.64 3.46 3.80 4.74 5.30

Performance fee with ρ = 10 (%p.a.) 2.35 3.16 3.51 4.45 5.01

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.54 0.55 0.55 0.55 0.51

Skewness −0.48 −0.45 −0.46 −0.45 −0.43

Excess kurtosis 1.62 1.56 1.61 1.54 1.42

Performance fee with ρ = 1 (%p.a.) 0.68 1.22 1.48 2.15 2.50

Performance fee with ρ = 3 (%p.a.) 0.31 0.84 1.10 1.78 2.13

Performance fee with ρ = 10 (%p.a.) 0.07 0.60 0.86 1.54 1.90

48

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Figure 2: Option-implied equity variance of S&P 500 firms

This Figure plots the time-series of the risk-neutral variance of the market (SVIX2t ) and of stocks’ average risk-

neutral variance (SVIX2

t ). We compute SVIX2t from equity index options on the S&P 500. SVIX

2

t is the value-weighted sum of S&P 500 stocks’ risk-neutral variance computed from individual firm equity options. Panels Athrough D present the variance series implied by equity options with maturities of one, three, six, 12, and 24months. The data is daily from January 1996 to October 2014.

Panel A. One-month horizon

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SVIXt2

SVIXt2

Panel C. Six-month horizon

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SVIXt2

SVIXt2

Panel B. Three-month horizon

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SVIXt2

SVIXt2

Panel D. One-year horizon

Sto

ck v

aria

nce

0.00

0.10

0.20

0.30

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SVIXt2

SVIXt2

Panel E. Two-year horizon

Sto

ck v

aria

nce

0.00

0.05

0.10

0.15

0.20

0.25

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SVIXt2

SVIXt2

49

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Figure 3: Beta, size, value, momentum, and option-implied equity variance

This Figure reports (equally-weighted) averages of risk-neutral stock variance (SVIX2i,t, computed from individual

firm equity options) of S&P 500 stocks, conditional on firm beta, size, book-to-market, and momentum. At everydate t, we assign stocks to decile portfolios based on on their characteristics and report the time-series averages ofSVIX2

i,t across deciles using SVIX2i,t-horizons of one year (Panels A to D).

Panel A. Beta

High P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Low

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Panel B. Size

Small P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Big

0.00

0.05

0.10

0.15

0.20

0.25

Panel C. Book-to-market

Value P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Growth

0.00

0.05

0.10

0.15

0.20

0.25

Panel D. Momentum

Winner P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Loser

0.00

0.05

0.10

0.15

0.20

0.25

50

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Figure 4: Beta, size, value, momentum, and option-implied equity variance

This Figure plots the time-series of risk-neutral stock variance (SVIX2i,t) of S&P 500 stocks, conditional on firm

beta, size, book-to-market, and momentum. The horizon is one year. At every date t, we classify firms as small,medium, or big when their market capitalization is in the bottom, middle, or top tertile of the time-t distributionacross all firms in our sample, and compute the (equally-weighted) average SVIX2

i,t. Similarly, we classify firms bytheir other characteristics at time t.

Panel A. Beta

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

HighMediumLow

Panel C. Book-to-market

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

ValueNeutralGrowth

Panel B. Size

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

SmallMediumBig

Panel D. Momentum

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

WinnerNeutralLoser

51

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Figure 5: Average equity excess returns

This Figure presents results on the relation between a firm’s equity excess returns and its risk-neutral variancemeasured relative to average risk-neutral stock variance. For firms that were constituents of the S&P 500 indexthroughout our sample period, we compute time-series averages of their excess returns and their stock volatility

relative to stocks’ average volatility (SVIX2i −SVIX

2). We multiply the stock variance estimate by 0.5 and plot the

pairwise combinations (blue crosses) for horizons of one, three, six, 12, and 24 months (Panels A to E). The blackline represents the regression fit to the individual firm observations with slope coefficient and R-squared reportedin the plot legend. Our theory implies that the slope coefficient of this regression should be one and that theintercept corresponds to the average excess return of the market. The red diamonds represent decile portfolios offirms sorted by SVIX2

i,t. Similarly, the triangles in orange represent portfolios of stocks formed according to firms’size and book-to-market.

Panel A. One-month excess returns

−0.02 0.00 0.02 0.04 0.06 0.08 0.10

0.00

0.10

0.20

0.30

0.5 × (SVIXi2 − SVIX2)

Exc

ess

retu

rn

Slope: 0.6, R−squ: 8.9%(SVIXi

2 − SVIX2) deciles3x3 Size x B/M

Panel C. Six-month excess returns

−0.02 0.00 0.02 0.04 0.06 0.08 0.10

0.0

0.1

0.2

0.3

0.5 × (SVIXi2 − SVIX2)

Exc

ess

retu

rn

Slope: 1, R−squ: 17.7%(SVIXi

2 − SVIX2) deciles3x3 Size x B/M

Panel B. Three-month excess returns

−0.02 0.00 0.02 0.04 0.06 0.08 0.100.

00.

10.

20.

30.5 × (SVIXi

2 − SVIX2)

Exc

ess

retu

rn

Slope: 0.79, R−squ: 13.6%(SVIXi

2 − SVIX2) deciles3x3 Size x B/M

Panel D. One-year excess returns

−0.02 0.00 0.02 0.04 0.06 0.08 0.10

0.0

0.1

0.2

0.3

0.4

0.5 × (SVIXi2 − SVIX2)

Exc

ess

retu

rn

Slope: 1.1, R−squ: 16.8%(SVIXi

2 − SVIX2) deciles3x3 Size x B/M

Panel E. Two-year excess returns

−0.02 0.00 0.02 0.04 0.06 0.08 0.10

0.0

0.1

0.2

0.3

0.4

0.5

0.5 × (SVIXi2 − SVIX2)

Exc

ess

retu

rn

Slope: 1.01, R−squ: 11.5%(SVIXi

2 − SVIX2) deciles3x3 Size x B/M

52

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Figure 6: Portfolios sorted by excess stock volatility

This Figure reports results on the relationship between equity portfolio returns in excess of the market and risk-neutral stock variance measured relative to stocks’ average risk-neutral variance. At the end of each month, wegroup all available firms into 10, 25, 50, or 100 portfolios (Panels A to D) based on their individual variance relative

to average variance, SVIX2i −SVIX

2; the horizon is one year. For each portfolio, we compute the time-series average

return in excess of the market and plot the pairwise combinations with the corresponding stock variance estimatemultiplied by 0.5. Our theory implies that the slope coefficient of this regression should be one. The black linerepresents the regression fit to the portfolio observations with slope coefficient and R-squared reported in the plotlegend. The sample period is January 1996 to October 2014.

Panel A. 10 portfolios

−0.02 0.00 0.02 0.04 0.06 0.08 0.10

0.00

0.02

0.04

0.06

0.08

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.59, R−squ: 93.2%

Panel C. 50 portfolios

0.00 0.05 0.10 0.15 0.20

0.00

0.05

0.10

0.15

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.63, R−squ: 85.9%

Panel B. 25 portfolios

0.00 0.05 0.10 0.15

0.00

0.04

0.08

0.12

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.62, R−squ: 90.2%

Panel D. 100 portfolios

0.00 0.05 0.10 0.15 0.20

0.00

0.05

0.10

0.15

0.20

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.64, R−squ: 80.9%

53

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Figure 7: Regression estimates in subsamples

This Figure summarizes results from regressing equity excess returns of S&P 500 firms on the risk-neutralvariance of the market variance, SVIX2

t , and the stock’s risk-neutral variance measured relative to stocks’

average risk-neutral variance, SVIX2i,t−SVIX

2

t . The data is monthly from January 1996 to October 2014,and we present results for yearly subsamples in Panel A and for three-year subsamples in Panel B. Thereturn horizon is one year and matches the maturity of the options used to compute SVIX2

t , SVIX2i,t, and

SVIX2

t . We report estimates for the pooled regression (18),

Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

We also report estimates from regressing equity returns in excess of the market on the stock’s risk-neutral

variance relative to average risk-neutral variance, SVIX2i,t−SVIX

2

t , using the pooled regression (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

The dashed line in each panel indicates the coefficient value predicted by our theory, i.e. β = 1 and γ = 0.5.

Panel A. One-year subsamples

● ●

Average of subsample estimates: 5.402

Subsamples

Sub

sam

ple

estim

ates

of

β

−10

−5

05

1015

20

1996 1999 2002 2005 2008 2011

● ●

●●

●●

Average of subsample estimates: 0.449

Subsamples

Sub

sam

ple

estim

ates

of

γ

−1.

0−

0.5

0.0

0.5

1.0

1.5

1996 1999 2002 2005 2008 2011

● excess returnsexcess market returns

Panel B. Three-year subsamples

Average of subsample estimates: −0.424

Subsamples

Sub

sam

ple

estim

ates

of

β

−20

−15

−10

−5

05

1996−1998 1999−2001 2002−2004 2005−2007 2008−2010 2011−2013

Average of subsample estimates: 0.510

Subsamples

Sub

sam

ple

estim

ates

of

γ

−0.

20.

00.

20.

40.

60.

81.

0

1996−1998 1999−2001 2002−2004 2005−2007 2008−2010 2011−2013

● excess returnsexcess market returns

54

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Figure 8: Portfolios sorted by beta, size, book-to-market, and momentum

This Figure reports results on the relationship between equity portfolio returns in excess of the market and risk-neutral stock variance measured relative to average firm-level risk-neutral variance. At the end of each month,we form 25 portfolios based on firms’ beta, size, book-to-market, or momentum (Panels A to D) and from a5× 5 conditional double sort on size and book-to-market. For each portfolio, we compute the time-series averagereturn in excess of the market and plot the pairwise combinations with the corresponding stock variance estimatemultiplied by 0.5. The black line represents the regression fit to the portfolio observations with slope coefficientand R-squared reported in the plot legend. Our theory implies that the slope coefficient of this regression shouldbe one. The sample period is January 1996 to October 2014.

Panel A. 25 Beta portfolios

−0.02 0.00 0.02 0.04 0.06 0.08 0.10 0.12

0.00

0.01

0.02

0.03

0.04

0.05

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.36, R−squ: 44.4%

Panel C. 25 B/M portfolios

0.01 0.02 0.03 0.04

0.00

0.02

0.04

0.06

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.92, R−squ: 11.5%

Panel B. 25 Size portfolios

0.00 0.01 0.02 0.03 0.04 0.050.

000.

050.

100.

150.5 × (SVIXi

2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 2.35, R−squ: 79.2%

Panel D. 25 Momentum portfolios

0.00 0.02 0.04 0.06 0.08

0.00

0.02

0.04

0.06

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 0.5, R−squ: 65.3%

Panel E. 25 Size × B/M portfolios

0.00 0.01 0.02 0.03 0.04

0.00

0.02

0.04

0.06

0.08

0.10

0.5 × (SVIXi2 − SVIX2)

Ret

urn

in e

xces

s of

the

mar

ket Slope: 1.52, R−squ: 55%

55

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Figure 9: Principal component analysis of unexpected returns

This Figure plots the first four principal components of unexpected returns in excess of the market. The returnhorizon is one year and data is sampled at a monthly frequency. We use the balanced panel of S&P 500 stockswith full time series coverage over our sample period from January 1996 to October 2014 and consider threealternative definitions of unexpected returns: the residuals computed using the pooled regressions, as in equation(20); residuals computed using the panel regressions with fixed effects, as in equation (21); and residuals computedusing the model with coefficients constrained by theory, as in equation (16). In the plots legends, we report theresidual variance explained by each of the principal components.

PC1

−4

−2

02

46

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.255)fixed effects (0.258)theory (0.246)

PC2

−4

−2

02

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.124)fixed effects (0.122)theory (0.131)

PC3

−6

−4

−2

02

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.084)fixed effects (0.080)theory (0.098)

PC4

−3

−2

−1

01

23

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.066)fixed effects (0.067)theory (0.063)

56

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Figure 10: Cross-sectional variation in expected returns

This Figure plots time-series of cross-sectional differences in one-year expected excess returns generated by ourmodel and by CAPM forecasts. The CAPM forecasts use conditional betas (estimated from historical returns)and a constant 6% p.a. equity premium. The plots show the difference in the 75%- and 25%-quantiles of expectedreturns (on the left) and the difference in the 90%- and 10%-quantiles of expected returns (on the right) for S&P100 stocks (Panel A) and S&P 500 stocks (Panel B). The data is monthly and covers S&P 500 stocks from January1996 to October 2014.

Panel A. Expected returns of S&P 100 firms

75% − 25% quantiles of expected returns

Diff

eren

ce in

exp

ecte

d re

turn

s

0.00

0.02

0.04

0.06

0.08

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

Model6% CAPM

90% − 10% quantiles of expected returns

Diff

eren

ce in

exp

ecte

d re

turn

s

0.00

0.05

0.10

0.15

0.20

0.25

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

Model6% CAPM

Panel B. Expected returns of S&P 500 firms

75% − 25% quantiles of expected returns

Diff

eren

ce in

exp

ecte

d re

turn

s

0.00

0.02

0.04

0.06

0.08

0.10

0.12

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

Model6% CAPM

90% − 10% quantiles of expected returns

Diff

eren

ce in

exp

ecte

d re

turn

s

0.00

0.05

0.10

0.15

0.20

0.25

Jan/96 Jan/00 Jan/04 Jan/08 Jan/12

Model6% CAPM

57

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Figure 11: Cumulative portfolio returns

This Figure plots the cumulative returns of daily rebalanced portfolios invested in S&P 500 stocks from January1996 to October 2014. We compare the performance of a portfolio based on model-implied expected returns to themarket benchmark (a value-weighted portfolio) and a naive diversification strategy (an equally-weighted portfolio).

For the model portfolio, we apply a rank weighting scheme, wXSi,t =rank[Et Ri,t+1]

θ∑i rank[Et Ri,t+1]θ

, which assigns portfolio

weights wXSi,t that increase in expected excess returns, does not allow for short positions, and ensures that the

investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls the aggressiveness of

the strategy; we set θ = 2. Panels A and B plot the cumulative portfolio returns when using forecasts based onone-month and one-year variance horizons. Panels C to F plot the cumulative portfolio returns for subsets of firmsbased on their size and book-to-market ratios with forecasts based on a one-year variance horizon.

Panel A. One-month horizon Panel B. One-year horizon

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

ModelVWEWcash

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

ModelVWEWcash

Panel C. Small value firms Panel D. Small growth firms

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

2050

Feb/96 Feb/99 Feb/02 Feb/05 Feb/08 Feb/11

ModelVWEWcash

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

20

Feb/96 Feb/99 Feb/02 Feb/05 Feb/08 Feb/11

ModelVWEWcash

Panel E. Big value firms Panel F. Big growth firms

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

Feb/96 Feb/99 Feb/02 Feb/05 Feb/08 Feb/11

ModelVWEWcash

Cum

ulat

ive

retu

rns

(log

scal

e)

12

510

Feb/96 Feb/99 Feb/02 Feb/05 Feb/08 Feb/11

ModelVWEWcash

58

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Internet Appendix for

What is the Expected Return on a Stock?

Internet Appendix – 1

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IA.A The linearization

In the body of the paper, we linearized β∗2i,t around β∗i,t = 1, that is, approximated

β∗2i,t ≈ 2β∗i,t − 1. More generally, we could replace (8) with

var∗tRi,t+1

Rf,t+1

= (cβ∗i,t + d) var∗tRg,t+1

Rf,t+1

+ var∗t ui,t+1, (IA.A.1)

where c and d are constants that can be chosen to satisfy some other requirement,

as discussed in footnote 5. If we do so then, using (7) and (IA.A.1) to eliminate the

dependence on β∗i,t, and imposing var∗t ui,t+1 = φi + ψt as in the main text,

EtRi,t+1

Rf,t+1

− 1 =1

cvar∗t

Ri,t+1

Rf,t+1

− d

cvar∗t

Rg,t+1

Rf,t+1

− 1

cvar∗t ui,t+1. (IA.A.2)

Value-weighting,

EtRm,t+1

Rf,t+1

− 1 =1

c

∑j

wj,t var∗tRj,t+1

Rf,t+1

− dc

var∗tRg,t+1

Rf,t+1

− 1

c

∑j

wj,t var∗t uj,t+1. (IA.A.3)

Subtracting (IA.A.3) from (IA.A.2),

EtRi,t+1 −Rm,t+1

Rf,t+1

= αi +1

c

(SVIX2

i,t−SVIX2

t

)where

∑i

wi,tαi = 0. (IA.A.4)

Similarly, substituting EtRm,t+1 − Rf,t+1 = Rf,t+1 SVIX2t into equation (IA.A.4), we

have

EtRi,t+1 −Rf,t+1

Rf,t+1

= αi + SVIX2t +

1

c

(SVIX2

i,t−SVIX2

t

)where

∑i

wi,tαi = 0.

We can calculate the residual that the linearization neglects using (7) and (8):

EtRi,t+1

Rf,t+1

− 1 =1

2var∗t

Rg,t+1

Rf,t+1

+1

2var∗t

Ri,t+1

Rf,t+1

− 1

2var∗t ui,t+1 −

1

2

(β∗i,t − 1

)2var∗t

Rg,t+1

Rf,t+1

.

Internet Appendix – 2

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Multiplying the above equation by the value weight wi,t and summing over i,

EtRm,t+1

Rf,t+1

− 1 =1

2var∗t

Rg,t+1

Rf,t+1

+1

2

∑j

wj,t var∗tRj,t+1

Rf,t+1

− 1

2

∑j

wj,t var∗t uj,t+1

− 1

2

∑j

wj,t(β∗j,t − 1

)2var∗t

Rg,t+1

Rf,t+1

.

Subtracting this from the previous equation and defining αi as in the main text,

EtRi,t+1 −Rm,t+1

Rf,t+1

= αi +1

2

(var∗t

Ri,t+1

Rf,t+1

−∑j

wj,t var∗tRj,t+1

Rf,t+1

)

− 1

2var∗t

Rg,t+1

Rf,t+1

[(β∗i,t − 1

)2 −∑j

wj,t(β∗j,t − 1

)2]. (IA.A.5)

In our baseline linearized equation (12), we are neglecting the final term on the right-

hand side of equation (IA.A.5). Thus our measure will overstate expected returns for

stocks i for which β∗i,t is unusually far from one, and will understate expected returns

for stocks for which β∗i,t is unusually close to one.

Unfortunately, β∗i,t is not directly observable. But if one is prepared to assume that

var∗tRg,t+1

Rf,t+1can be proxied by SVIX2

t , then it becomes possible to get a rough sense of

the internal consistency of our approach by using equations (7) and (17) to compute a

firm’s risk-neutral beta as

β∗i,t = 1 +1

2

(SVIX2

i,t−SVIX2

t

)SVIX2

t

.

The third term in equation (IA.A.5) then becomes

approximation error = −1

2SVIX2

t

[(β∗i,t − 1

)2 −∑j

wj,t(β∗j,t − 1

)2].

Figure IA.15 in the Internet Appendix plots the empirical distributions of (β∗i,t−1)2

and of approximation errors, defined in this way, at horizons of one, three, six, 12, and

24 months. At the one year horizon, we find that the implied approximation errors are

within ±2.5% p.a. for over 90% of our observations of S&P 100 firms and around 80%

of observations of S&P 500 firms.

Internet Appendix – 3

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Table IA.1: Expected excess returns of S&P 100 stock portfolios sorted by SVIX

This Table presents results from regressing portfolio equity excess returns on the risk-neutral variance of the marketvariance (SVIX2

t ) and on the portfolio’s risk-neutral variance measured relative to portfolios’ average risk-neutral

variance(

SVIX2i,t−SVIX

2

t

). At the end of every month, we sort S&P 100 firms into 25 portfolios based on their

SVIX2i,t. The data is monthly from January 1996 to October 2014. The column labels indicate the return horizons

ranging from one month to two years. The return horizons match the maturities of the options used to compute

SVIX2t , SVIX2

i,t, and SVIX2

t . Panel A reports estimates of the pooled regression specified in equation (18),

Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with portfolio fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in

parentheses are standard errors obtained from the block bootstrap procedure described in Appendix B. In eachpanel, we report the regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficientstake the values predicted by our theory (zero intercept, β = 1, and γ = 0.5) and for tests whether β and γ areequal to zero. For the pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtainedwhen the coefficients are fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.074 0.040 -0.008 -0.002 -0.011

(0.063) (0.074) (0.053) (0.068) (0.070)

β -0.098 0.857 2.140 1.954 2.033

(1.997) (2.272) (1.426) (1.372) (1.522)

γ 0.438 0.497 0.728 0.769 0.690

(0.279) (0.334) (0.327) (0.292) (0.214)

Pooled adj-R2 (%) 0.390 1.460 6.124 9.738 11.524

α, β, γ 0.523 0.693 0.713 0.619 0.669

β = γ = 0 0.174 0.302 0.062 0.030 0.003

γ = 0.5 0.823 0.993 0.486 0.358 0.374

γ = 0 0.117 0.137 0.026 0.009 0.001

Theory adj-R2 (%) 0.016 0.922 4.087 6.174 7.951

Panel B. Portfolio fixed-effects regressions∑wiαi 0.082 0.048 0.006 0.010 -0.004

(0.060) (0.070) (0.049) (0.063) (0.067)

β -0.200 0.731 1.903 1.745 1.918

(1.963) (2.210) (1.377) (1.299) (1.451)

γ 0.600 0.726 1.162 1.141 0.922

(0.377) (0.501) (0.460) (0.402) (0.310)

Panel adj-R2 (%) 1.222 4.286 11.942 19.436 23.417∑wiαi, β, γ 0.305 0.536 0.416 0.325 0.509

β = γ = 0 0.147 0.308 0.039 0.017 0.012

γ = 0.5 0.792 0.652 0.150 0.111 0.173

γ = 0 0.112 0.147 0.012 0.005 0.003

Internet Appendix – 4

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Table IA.2: Expected returns in excess of the market of S&P 100 stock portfolios sortedby SVIX

This Table presents results from regressing portfolio returns in excess of the market on the portfolio’s risk-neutral

variance measured relative to portfolios’ average risk-neutral variance(

SVIX2i,t−SVIX

2

t

). At the end of every

month, we sort S&P 100 firms into 25 portfolios based on their SVIX2i,t. The data is monthly from January 1996

to October 2014. The column labels indicate the return horizons ranging from one month to two years. The return

horizons match the maturities of the options used to compute SVIX2i,t and SVIX

2

t . Panel A reports estimates ofthe pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with portfolio fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in

parentheses are standard errors obtained from the block bootstrap procedure described in Appendix B. In eachpanel, we report the regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficientstake the values predicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. Forthe pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficientsare fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.008 0.008 0.006 0.008 0.011

(0.014) (0.013) (0.014) (0.015) (0.015)

γ 0.514 0.569 0.768 0.754 0.672

(0.268) (0.309) (0.308) (0.287) (0.220)

Pooled adj-R2 (%) 1.043 2.826 7.690 11.814 12.436

H0 : α = 0, γ = 0.5 0.831 0.764 0.496 0.347 0.265

H0 : γ = 0.5 0.957 0.822 0.385 0.376 0.433

H0 : γ = 0 0.055 0.065 0.013 0.009 0.002

Theory adj-R2 (%) 1.023 2.714 6.593 10.093 10.840

Panel B. Portfolio fixed-effects regressions∑i wiαi 0.013 0.013 0.012 0.012 0.014

(0.014) (0.013) (0.014) (0.015) (0.015)

γ 0.731 0.860 1.232 1.096 0.869

(0.343) (0.436) (0.395) (0.363) (0.308)

Panel adj-R2 (%) 1.333 4.123 11.017 15.493 16.729

H0 :∑i wiαi = 0, γ = 0.5 0.498 0.413 0.089 0.105 0.283

H0 : γ = 0.5 0.501 0.408 0.064 0.100 0.232

H0 : γ = 0 0.033 0.048 0.002 0.003 0.005

Internet Appendix – 5

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Table IA.3: Expected excess returns of S&P 500 stock portfolios sorted by SVIX

This Table presents results from regressing portfolio equity excess returns on the risk-neutral variance of the marketvariance (SVIX2

t ) and on the portfolio’s risk-neutral variance measured relative to portfolios’ average risk-neutral

variance(

SVIX2i,t−SVIX

2

t

). At the end of every month, we sort S&P 500 firms into 100 portfolios based on their

SVIX2i,t. The data is monthly from January 1996 to October 2014. The column labels indicate the return horizons

ranging from one month to two years. The return horizons match the maturities of the options used to compute

SVIX2t , SVIX2

i,t, and SVIX2

t . Panel A reports estimates of the pooled regression specified in equation (18),

Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with portfolio fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in

parentheses are standard errors obtained from the block bootstrap procedure described in Appendix B. In eachpanel, we report the regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficientstake the values predicted by our theory (zero intercept, β = 1, and γ = 0.5) and for tests whether β and γ areequal to zero. For the pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtainedwhen the coefficients are fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.058 0.022 -0.037 -0.021 -0.055

(0.074) (0.079) (0.059) (0.071) (0.077)

β 0.693 1.813 3.420 2.978 3.856

(2.318) (2.409) (1.562) (1.614) (1.813)

γ 0.254 0.285 0.446 0.490 0.327

(0.296) (0.285) (0.318) (0.313) (0.200)

Pooled adj-R2 (%) 0.236 1.421 6.065 8.247 12.003

α, β, γ 0.308 0.206 0.168 0.190 0.021

β = γ = 0 0.686 0.593 0.077 0.104 0.040

γ = 0.5 0.405 0.451 0.865 0.975 0.386

γ = 0 0.391 0.317 0.160 0.117 0.102

Theory adj-R2 (%) -0.143 0.314 2.804 3.735 3.833

Panel B. Portfolio fixed-effects regressions∑wiαi 0.063 0.027 -0.023 -0.009 -0.051

(0.069) (0.072) (0.054) (0.067) (0.073)

β 0.571 1.705 3.168 2.740 3.779

(2.245) (2.293) (1.459) (1.506) (1.714)

γ 0.426 0.429 0.772 0.796 0.423

(0.477) (0.500) (0.551) (0.552) (0.384)

Panel adj-R2 (%) 1.084 4.389 11.833 18.108 24.333∑wiαi, β, γ 0.438 0.402 0.269 0.255 0.017

β = γ = 0 0.655 0.668 0.082 0.134 0.085

γ = 0.5 0.877 0.886 0.622 0.591 0.841

γ = 0 0.371 0.391 0.161 0.149 0.271

Internet Appendix – 6

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Table IA.4: Expected returns in excess of the market of S&P 500 stock portfolios sortedby SVIX

This Table presents results from regressing portfolio returns in excess of the market on the portfolio’s risk-neutral

variance measured relative to portfolios’ average risk-neutral variance(

SVIX2i,t−SVIX

2

t

). At the end of every

month, we sort S&P 500 firms into 100 portfolios based on their SVIX2i,t. The data is monthly from January 1996

to October 2014. The column labels indicate the return horizons ranging from one month to two years. The return

horizons match the maturities of the options used to compute SVIX2i,t and SVIX

2

t . Panel A reports estimates ofthe pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with portfolio fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in

parentheses are standard errors obtained from the block bootstrap procedure described in Appendix B. In eachpanel, we report the regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficientstake the values predicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. Forthe pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficientsare fixed at the values predicted by our theory.

Horizon 30 days 91 days 182 days 365 days 730 days

Panel A. Pooled regressions

α 0.015 0.016 0.013 0.014 0.018

(0.014) (0.015) (0.016) (0.019) (0.019)

γ 0.345 0.399 0.537 0.533 0.357

(0.286) (0.271) (0.304) (0.297) (0.202)

Pooled adj-R2 (%) 0.506 1.635 4.517 7.087 5.125

H0 : α = 0, γ = 0.5 0.552 0.537 0.626 0.619 0.654

H0 : γ = 0.5 0.586 0.710 0.904 0.912 0.479

H0 : γ = 0 0.228 0.140 0.077 0.073 0.078

Theory adj-R2 (%) 0.378 1.403 4.243 6.553 3.509

Panel B. Portfolio fixed-effects regressions∑i wiαi 0.019 0.021 0.020 0.019 0.019

(0.014) (0.014) (0.016) (0.019) (0.020)

γ 0.630 0.705 0.993 0.898 0.516

(0.437) (0.445) (0.479) (0.478) (0.351)

Panel adj-R2 (%) 0.785 2.686 7.289 10.396 8.080

H0 :∑i wiαi = 0, γ = 0.5 0.362 0.271 0.180 0.257 0.578

H0 : γ = 0.5 0.766 0.644 0.303 0.406 0.964

H0 : γ = 0 0.149 0.113 0.038 0.060 0.141

Internet Appendix – 7

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Table IA.5: Excess returns of characteristics/SVIXi,t double-sorted portfolios

This Table presents results from regressing portfolio equity excess returns on the risk-neutral variance of the marketvariance (SVIX2

t ) and on the portfolio’s risk-neutral variance measured relative to portfolios’ average risk-neutral

variance(

SVIX2i,t−SVIX

2

t

). At the end of each month, we sort S&P 500 firms into 5x5-double sorted portfolios

based on firm characteristics and SVIXi,t. We first assign firms to quintile portfolios based on their CAPM beta,size, book-to-market, or momentum. In the second step, we sort stocks within each of the characteristics portfoliosinto SVIXi,t-quintiles, providing us with a total of 25 conditionally double-sorted portfolios. The one-year horizon

of the portfolio returns matches the 365 day-maturity of the options used to compute SVIX2i,t and SVIX

2

t . PanelA reports estimates of the pooled regression specified in equation (18),

Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with portfolio fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in

parentheses are standard errors obtained from the block bootstrap procedure described in Appendix B. In eachpanel, we report the regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficientstake the values predicted by our theory (zero intercept, β = 1, and γ = 0.5) and for tests whether β and γ areequal to zero. For the pooled regressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtainedwhen the coefficients are fixed at the values predicted by our theory.

Beta Size B/M Mom

Panel A. Pooled regressions

α -0.020 -0.021 -0.021 -0.021

(0.071) (0.071) (0.071) (0.071)

β 2.974 2.963 3.024 2.960

(1.603) (1.600) (1.619) (1.606)

γ 0.450 0.520 0.446 0.511

(0.326) (0.340) (0.342) (0.335)

Pooled adj-R2 (%) 9.184 9.879 9.178 10.036

α, β, γ 0.170 0.203 0.159 0.185

β = γ = 0 0.119 0.107 0.127 0.116

γ = 0.5 0.877 0.954 0.874 0.983

γ = 0 0.168 0.126 0.193 0.141

Theory adj-R2 (%) 3.468 4.237 3.152 3.943

Panel B. Portfolio fixed-effects regressions∑wiαi -0.014 -0.019 -0.019 -0.009

(0.068) (0.072) (0.069) (0.067)

β 2.790 2.723 2.908 2.756

(1.502) (1.503) (1.563) (1.525)

γ 0.688 0.826 0.593 0.772

(0.554) (0.599) (0.563) (0.542)

Panel adj-R2 (%) 21.174 22.404 21.481 21.908∑wiαi, β, γ 0.250 0.314 0.232 0.249

β = γ = 0 0.153 0.132 0.152 0.133

γ = 0.5 0.734 0.586 0.868 0.616

γ = 0 0.214 0.168 0.292 0.154

Internet Appendix – 8

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Table IA.6: Excess returns of SVIXi,t/characteristics double-sorted portfolios

This Table presents results from regressing portfolio equity excess returns on the risk-neutral variance of the market vari-ance (SVIX2

t ) and on the portfolio’s risk-neutral variance measured relative to portfolios’ average risk-neutral variance(SVIX2

i,t−SVIX2

t

). At the end of each month, we sort S&P 500 firms into 5x5-double sorted portfolios based on SVIXi,t

and firm characteristics. We first assign firms to quintile portfolios based on SVIXi,t. In the second step, we sort stocks withineach SVIXi,t-portfolio in quintiles based on their CAPM beta, size, book-to-market, or momentum, providing us with a totalof 25 conditionally double-sorted portfolios. The one-year horizon of the portfolio returns matches the 365 day-maturity of the

options used to compute SVIX2i,t and SVIX

2

t . Panel A reports estimates of the pooled regression specified in equation (18),

Ri,t+1 −Rf,t+1

Rf,t+1= α+ β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1.

Panel B reports results for the panel regression with portfolio fixed effects specified in equation (19),

Ri,t+1 −Rf,t+1

Rf,t+1= αi + β SVIX2

t +γ(

SVIX2i,t−SVIX

2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of portfolio fixed effects. Values in parentheses are

standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we report the regressions’adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the values predicted by our theory (zerointercept, β = 1, and γ = 0.5) and for tests whether β and γ are equal to zero. For the pooled regressions, the row labelled‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficients are fixed at the values predicted by our theory.

Beta Size B/M Mom

Panel A. Pooled regressions

α -0.020 -0.021 -0.021 -0.021

(0.071) (0.071) (0.071) (0.071)

β 3.007 2.971 3.011 2.968

(1.621) (1.607) (1.627) (1.605)

γ 0.402 0.508 0.449 0.502

(0.338) (0.353) (0.340) (0.355)

Pooled adj-R2 (%) 8.243 9.433 9.091 9.556

α, β, γ 0.149 0.201 0.169 0.167

β = γ = 0 0.136 0.114 0.124 0.128

γ = 0.5 0.773 0.982 0.882 0.935

γ = 0 0.234 0.150 0.186 0.184

Theory adj-R2 (%) 2.403 3.745 3.056 3.292

Panel B. Portfolio fixed-effects regressions∑wiαi -0.013 -0.020 -0.015 -0.007

(0.068) (0.071) (0.067) (0.067)

β 2.796 2.719 2.809 2.700

(1.528) (1.499) (1.538) (1.496)

γ 0.678 0.831 0.709 0.845

(0.573) (0.638) (0.588) (0.616)

Panel adj-R2 (%) 20.408 21.957 21.623 21.596∑wiαi, β, γ 0.250 0.347 0.269 0.254

β = γ = 0 0.158 0.140 0.151 0.140

γ = 0.5 0.756 0.603 0.722 0.576

γ = 0 0.237 0.192 0.228 0.170

Internet Appendix – 9

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Table IA.7: Excess market returns of SVIXi,t/characteristics double-sorted portfolios

This Table presents results from regressing portfolio equity returns in excess of the market on the portfolio stock’s

risk-neutral variance measured relative to stocks’ average risk-neutral variance, SVIX2i,t−SVIX

2

t . The data ismonthly from January 1996 to October 2014. At the end of each month, we sort S&P 500 firms into 5x5-doublesorted portfolios based on SVIXi,t and firm characteristics. We first assign firms to quintile portfolios based onSVIXi,t. In the second step, we sort stocks within each SVIXi,t-portfolio in quintiles based on their CAPM beta,size, book-to-market, or momentum, providing us with a total of 25 conditionally double-sorted portfolios. Theone-year horizon of the portfolio returns matches the 365 day-maturity of the options used to compute SVIX2

i,t and

SVIX2

t . Panel A reports estimates of the pooled regression specified in equation (20),

Ri,t+1 −Rm,t+1

Rf,t+1= α+ γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1.

Panel B reports estimates of the panel regression with portfolio fixed effects specified in equation (21),

Ri,t+1 −Rm,t+1

Rf,t+1= αi + γ

(SVIX2

i,t−SVIX2

t

)+ εi,t+1,

where∑i wiαi reports the time-series average of the value-weighted sum of firm fixed effects. Values in parentheses

are standard errors obtained from the block bootstrap procedure described in Appendix B. In each panel, we reportthe regressions’ adjusted-R2 and p-values of Wald tests testing whether the regression coefficients take the valuespredicted by our theory (zero intercept and γ = 0.5) and for a test whether γ is equal to zero. For the pooledregressions, the row labelled ‘theory adj-R2 (%)’ reports the adjusted-R2 obtained when the coefficients are fixedat the values predicted by our theory.

Beta Size B/M Mom

Panel A. Pooled regressions

α 0.016 0.014 0.015 0.014

(0.020) (0.020) (0.020) (0.019)

γ 0.455 0.565 0.507 0.555

(0.332) (0.334) (0.328) (0.341)

Pooled adj-R2 (%) 6.343 8.954 7.967 9.223

H0 : α = 0, γ = 0.5 0.652 0.596 0.633 0.629

H0 : γ = 0.5 0.891 0.846 0.982 0.937

H0 : γ = 0 0.171 0.091 0.122 0.122

Theory adj-R2 (%) 5.483 8.065 7.092 7.249

Panel B. Portfolio fixed-effects regressions∑i wiαi 0.016 0.007 0.015 0.019

(0.017) (0.007) (0.017) (0.018)

γ 0.803 0.964 0.846 0.960

(0.539) (0.551) (0.530) (0.555)

Panel adj-R2 (%) 11.181 15.302 13.339 14.485

H0 :∑i wiαi = 0, γ = 0.5 0.377 0.264 0.384 0.216

H0 : γ = 0.5 0.574 0.400 0.514 0.408

H0 : γ = 0 0.137 0.080 0.111 0.084

Internet Appendix – 10

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Table IA.8: Principal component analysis of unexpected returns

This Table reports results for a principal component analysis of unexpected returns in excess of the market. The

return horizon is one year and data is sampled at a monthly frequency. We use the balanced panel of S&P 500

stocks with full time series coverage over our sample period from January 1996 to October 2014 and consider

three alternative definitions of unexpected returns: the residuals computed using the pooled regressions, as in

equation (20), in Panel A; residuals computed using the panel regressions with fixed effects, as in equation (21),

in Panel B; and residuals computed using the model with coefficients constrained by theory, as in equation (16),

in Panel C. In each panel, the first two rows report the variance and the cumulative variance explained by the

principal components. The other rows report R2 from regressions of PC1 to PC4 on (i) the risk-neutral variance

of the market variance, SVIX2t ; (ii) stocks’ average risk-neutral variance, SVIX

2

t ; (iii) SVIX2t /SVIX

2

t , a measure of

average risk-neutral correlation, see Appendix A; (iv) SVIX2t −SVIX

2

t .

Panel A: Pooled regression residuals

PC1 PC2 PC3 PC4

Variance explained 25.50 12.41 8.43 6.60

Cumulative variance explained 25.50 37.90 46.34 52.94

SVIX2t 2.03 2.49 15.71 2.09

SVIX2t 2.62 1.03 17.97 1.42

SVIX2t /SVIX2

t 13.93 0.50 0.15 5.99

SVIX2t −SVIX2

t 10.89 0.17 12.19 7.27

Panel B: Fixed effects regression residuals

PC1 PC2 PC3 PC4

Variance explained 24.62 13.06 9.79 6.34

Cumulative variance explained 24.62 37.68 47.47 53.81

SVIX2t 1.26 11.76 17.61 0.07

SVIX2t 2.60 7.42 13.74 4.65

SVIX2t /SVIX2

t 10.80 1.07 1.54 3.77

SVIX2t −SVIX2

t 9.56 2.73 6.57 10.88

Panel C: Theory residuals

PC1 PC2 PC3 PC4

Variance explained 25.77 12.23 7.98 6.65

Cumulative variance explained 25.77 38.00 45.98 52.63

SVIX2t 2.23 1.15 9.92 5.66

SVIX2t 2.76 0.23 16.89 0.05

SVIX2t /SVIX2

t 15.16 0.50 0.16 6.92

SVIX2t −SVIX2

t 11.61 0.00 14.81 3.72

Internet Appendix – 11

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Table IA.9: Principal component analysis of unexpected portfolio returns

This Table reports results for a principal component analysis of unexpected returns in excess of the market. The

return horizon is one year and data is sampled at a monthly frequency. Every month from January 1996 to October

2014, we sort all available S&P 500 firms into 100 portfolios based on their SVIXi,t and consider three alternative

definitions of unexpected returns: the residuals computed using the pooled regressions, as in equation (20), in

Panel A; residuals computed using the panel regressions with fixed effects, as in equation (21), in Panel B; and

residuals computed using the model with coefficients constrained by theory, as in equation (16), in Panel C. In each

panel, the first two rows report the variance and the cumulative variance explained by the principal components.

The other rows report R2 from regressions of PC1 to PC4 on (i) the risk-neutral variance of the market variance,

SVIX2t ; (ii) stocks’ average risk-neutral variance, SVIX

2

t ; (iii) SVIX2t /SVIX

2

t , a measure of average risk-neutral

correlation, see Appendix A; (iv) SVIX2t −SVIX

2

t .

Panel A: Pooled regression residuals

PC1 PC2 PC3 PC4

Variance explained 27.91 16.75 4.32 2.85

Cumulative variance explained 27.91 44.66 48.98 51.83

SVIX2t 12.50 9.54 0.14 0.00

SVIX2t 0.40 27.79 0.80 0.14

SVIX2t /SVIX2

t 20.08 4.54 1.22 0.11

SVIX2t −SVIX2

t 6.87 28.76 0.97 0.20

Panel B: Fixed effects regression residuals

PC1 PC2 PC3 PC4

Variance explained 27.88 16.93 4.30 2.84

Cumulative variance explained 27.88 44.81 49.11 51.95

SVIX2t 13.65 9.27 0.12 0.00

SVIX2t 0.15 28.50 0.76 0.13

SVIX2t /SVIX2

t 19.23 5.11 1.20 0.12

SVIX2t −SVIX2

t 5.69 29.96 0.94 0.19

Panel C: Theory residuals

PC1 PC2 PC3 PC4

Variance explained 29.39 14.37 4.43 2.94

Cumulative variance explained 29.39 43.75 48.18 51.12

SVIX2t 4.03 7.98 0.52 0.00

SVIX2t 7.39 16.81 1.35 0.25

SVIX2t /SVIX2

t 26.70 1.02 1.30 0.12

SVIX2t −SVIX2

t 21.05 15.67 1.34 0.40

Internet Appendix – 12

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Table IA.10: Portfolio performance with monthly rebalancing (θ = 1)

This Table summarizes the performance of monthly rebalanced portfolios invested in S&P 500 stocks from January1996 to October 2014. We compare the performance of a portfolio based on model-implied expected excess returnsto the market benchmark (a value-weighted portfolio) and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy; we set θ = 1. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio. The column labels indicate the variance horizon used in themodel forecast.

30 days 91 days 182 days 365 days 730 days

Portfolio performance based on model forecasts

Mean (%p.a.) 10.51 11.03 11.06 11.45 11.07

Sd (%p.a.) 21.73 21.77 21.81 21.82 21.88

Sharpe ratio (p.a.) 0.48 0.51 0.51 0.52 0.51

Skewness −0.24 −0.21 −0.21 −0.21 −0.21

Excess kurtosis 1.59 1.51 1.58 1.50 1.34

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.45 0.44 0.43 0.41 0.36

Skewness −0.61 −0.60 −0.59 −0.58 −0.54

Excess kurtosis 0.82 0.76 0.73 0.67 0.57

Performance fee with ρ = 1 (%p.a.) 3.04 3.60 3.79 4.43 4.83

Performance fee with ρ = 3 (%p.a.) 2.74 3.30 3.50 4.14 4.54

Performance fee with ρ = 10 (%p.a.) 2.55 3.11 3.31 3.96 4.36

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.54 0.55 0.55 0.55 0.51

Skewness −0.48 −0.45 −0.46 −0.45 −0.43

Excess kurtosis 1.62 1.56 1.61 1.54 1.42

Performance fee with ρ = 1 (%p.a.) 0.62 0.90 1.01 1.39 1.58

Performance fee with ρ = 3 (%p.a.) 0.41 0.69 0.80 1.18 1.37

Performance fee with ρ = 10 (%p.a.) 0.28 0.55 0.67 1.05 1.24

Internet Appendix – 13

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Table IA.11: Portfolio performance with daily rebalancing (θ = 1)

This Table summarizes the performance of daily rebalanced portfolios invested in S&P 500 stocks from January1996 to October 2014. We compare the performance of a portfolio based on model-implied expected excess returnsto the market benchmark (a value-weighted portfolio) and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy; we set θ = 1. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio. The column labels indicate the variance horizon used in themodel forecast.

30 days 91 days 182 days 365 days 730 days

Portfolio performance based on model forecasts

Mean (%p.a.) 12.54 12.33 12.25 12.24 12.23

Sd (%p.a.) 24.88 24.92 24.91 24.84 24.75

Sharpe ratio (p.a.) 0.50 0.49 0.49 0.49 0.49

Skewness −0.11 −0.12 −0.12 −0.12 −0.13

Excess kurtosis 7.41 7.30 7.26 7.17 7.12

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.38 0.38 0.38 0.38 0.38

Skewness −0.18 −0.18 −0.18 −0.18 −0.18

Excess kurtosis 6.24 6.24 6.24 6.24 6.24

Performance fee with ρ = 1 (%p.a.) 4.55 4.34 4.26 4.26 4.25

Performance fee with ρ = 3 (%p.a.) 4.27 4.05 3.97 3.97 3.97

Performance fee with ρ = 10 (%p.a.) 4.07 3.86 3.78 3.78 3.78

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.51 0.51 0.51 0.51 0.51

Skewness −0.21 −0.21 −0.21 −0.21 −0.21

Excess kurtosis 7.24 7.24 7.24 7.24 7.24

Performance fee with ρ = 1 (%p.a.) 1.59 1.37 1.30 1.29 1.29

Performance fee with ρ = 3 (%p.a.) 1.33 1.13 1.05 1.05 1.05

Performance fee with ρ = 10 (%p.a.) 1.19 0.97 0.89 0.90 0.90

Internet Appendix – 14

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Table IA.12: Portfolio performance with daily rebalancing

This Table summarizes the performance of daily rebalanced portfolios invested in S&P 500 stocks from January1996 to October 2014. We compare the performance of a portfolio based on model-implied expected excess returnsto the market benchmark (a value-weighted portfolio) and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy, and we set θ = 2. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio. The column labels indicate the variance horizon used in themodel forecast.

30 days 91 days 182 days 365 days 730 days

Portfolio performance based on model forecasts

Mean (%p.a.) 13.72 13.32 13.20 13.18 13.19

Sd (%p.a.) 27.69 27.75 27.72 27.59 27.43

Sharpe ratio (p.a.) 0.50 0.48 0.48 0.48 0.48

Skewness −0.04 −0.04 −0.04 −0.05 −0.06

Excess kurtosis 7.57 7.39 7.31 7.15 7.04

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.38 0.38 0.38 0.38 0.38

Skewness −0.18 −0.18 −0.18 −0.18 −0.18

Excess kurtosis 6.24 6.24 6.24 6.24 6.24

Performance fee with ρ = 1 (%p.a.) 5.36 4.96 4.84 4.84 4.86

Performance fee with ρ = 3 (%p.a.) 4.88 4.48 4.36 4.37 4.41

Performance fee with ρ = 10 (%p.a.) 4.57 4.17 4.05 4.06 4.11

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.51 0.51 0.51 0.51 0.51

Skewness −0.21 −0.21 −0.21 −0.21 −0.21

Excess kurtosis 7.24 7.24 7.24 7.24 7.24

Performance fee with ρ = 1 (%p.a.) 2.39 1.99 1.87 1.87 1.90

Performance fee with ρ = 3 (%p.a.) 1.95 1.55 1.43 1.44 1.47

Performance fee with ρ = 10 (%p.a.) 1.68 1.29 1.17 1.18 1.23

Internet Appendix – 15

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Table IA.13: Performance of size- and value-portfolios with daily rebalancing

This Table summarizes the performance of daily rebalanced portfolios invested in a subset of S&P 500 stocks,conditional on firm size and book-to-market. At every portfolio rebalancing date t, we classify firms as small(big) when their market capitalization is in the bottom (top) tertile of the time-t distribution across all firms inour sample. Similarly, we classify firms as value (growth) stocks when their book-to-market ratio is within thetop (bottom) tertile of the book-to-market distribution at time t. We report results for firms that are classifiedas small value, small growth, big value, and big growth. The sample period is from January 1996 to October2014. We compare the performance of a portfolio based on model-implied expected excess returns (based on avariance horizon of one year) to a value-weighted portfolio and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy, and we set θ = 2. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio.

Small Big Value Growth

Portfolio performance based on model forecasts

Mean (%p.a.) 21.50 9.73 19.21 12.06

Sd (%p.a.) 30.82 26.66 29.39 29.36

Sharpe ratio (p.a.) 0.70 0.36 0.65 0.41

Skewness 0.09 0.06 0.03 0.26

Excess kurtosis 6.51 6.21 9.33 6.15

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.52 0.31 0.38 0.31

Skewness −0.14 −0.11 −0.18 −0.04

Excess kurtosis 6.37 5.70 8.54 4.95

Performance fee with ρ = 1 (%p.a.) 8.56 2.84 9.80 4.71

Performance fee with ρ = 3 (%p.a.) 8.01 2.44 9.36 4.13

Performance fee with ρ = 10 (%p.a.) 7.66 2.18 9.08 3.75

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.62 0.37 0.56 0.41

Skewness −0.08 −0.16 −0.20 −0.02

Excess kurtosis 6.70 6.24 8.07 5.89

Performance fee with ρ = 1 (%p.a.) 5.93 1.66 5.84 2.37

Performance fee with ρ = 3 (%p.a.) 5.43 1.25 5.40 1.83

Performance fee with ρ = 10 (%p.a.) 5.11 1.01 5.11 1.50

Internet Appendix – 16

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Table IA.14: Performance of size/value-portfolios with daily rebalancing

This Table summarizes the performance of daily rebalanced portfolios invested in a subset of S&P 500 stocks,conditional on firm size and book-to-market. At every portfolio rebalancing date t, we classify firms as small(big) when their market capitalization is in the bottom (top) tertile of the time-t distribution across all firms inour sample. Similarly, we classify firms as value (growth) stocks when their book-to-market ratio is within thetop (bottom) tertile of the book-to-market distribution at time t. We report results for firms that are classifiedas small value, small growth, big value, and big growth. The sample period is from January 1996 to October2014. We compare the performance of a portfolio based on model-implied expected excess returns (based on avariance horizon of one year) to a value-weighted portfolio and a naive diversification strategy (an equally-weightedportfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short positions,

and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The parameter θ controls

the aggressiveness of the strategy, and we set θ = 2. For the model forecast-based portfolios, we report annualizedaverage excess returns along with their associated standard deviations and Sharpe ratios as well as their skewnessand excess kurtosis. For the benchmark portfolios we additionally report the performance fee (following Fleminget al., 2001) that a risk-averse investor with relative risk aversion ρ ∈ {1, 3, 10} would be willing to pay to switchfrom the benchmark strategy to the model portfolio.

Small Value Small Growth Big Value Big Growth

Portfolio performance based on model forecasts

Mean (%p.a.) 28.01 19.37 9.28 9.59

Sd (%p.a.) 34.34 33.15 28.85 27.93

Sharpe ratio (p.a.) 0.82 0.58 0.32 0.34

Skewness 0.20 0.37 0.08 0.23

Excess kurtosis 8.40 6.69 10.59 6.61

Comparison to value-weighted portfolio

Sharpe ratio (p.a.) 0.56 0.46 0.27 0.30

Skewness −0.23 0.12 −0.19 −0.02

Excess kurtosis 8.14 5.95 6.65 4.61

Performance fee with ρ = 1 (%p.a.) 12.74 7.19 2.29 2.54

Performance fee with ρ = 3 (%p.a.) 12.03 6.52 1.88 2.05

Performance fee with ρ = 10 (%p.a.) 11.60 6.09 1.63 1.75

Comparison to equally-weighted portfolio

Sharpe ratio (p.a.) 0.68 0.54 0.33 0.32

Skewness −0.07 0.15 −0.23 −0.00

Excess kurtosis 7.66 6.81 7.18 5.58

Performance fee with ρ = 1 (%p.a.) 9.30 5.09 1.23 2.31

Performance fee with ρ = 3 (%p.a.) 8.65 4.45 0.79 1.82

Performance fee with ρ = 10 (%p.a.) 8.24 4.04 0.51 1.53

Internet Appendix – 17

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Figure IA.1: Option-implied equity variance of S&P 100 firms

This Figure plots the time-series of the risk-neutral variance of the market (SVIX2t ) and of stocks’ average risk-

neutral variance (SVIX2

t ). We compute SVIX2t from equity index options on the S&P 100. SVIX

2

t is the value-weighted sum of S&P 100 stocks’ risk-neutral variance computed from individual firm equity options. Panels Athrough E present the variance series implied by equity options with maturities of one, three, six, 12, and 24months. The data is daily from January 1996 to October 2014.

Panel A. One-month horizon

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

SVIXt2

SVIXt2

Panel C. Six-month horizon

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

SVIXt2

SVIXt2

Panel B. Three-month horizon

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

SVIXt2

SVIXt2

Panel D. One-year horizon

Sto

ck v

aria

nce

0.00

0.10

0.20

0.30

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

SVIXt2

SVIXt2

Panel E. Two-year horizon

Sto

ck v

aria

nce

0.00

0.05

0.10

0.15

0.20

0.25

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

SVIXt2

SVIXt2

Internet Appendix – 18

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Figure IA.2: A measure of average risk-neutral correlation between stocks

This Figure plots the time-series of the ratio of the risk-neutral variance of the market to stocks’ average risk-neutral

variance (SVIX2t /SVIX

2

t ); in the appendix, we show that this quantity is an approximate measure of average risk-neutral correlation. We compute SVIX2

t from equity index options on the S&P 100 (Panels A and B) and S&P

500 (Panels C and D). SVIX2

t is the corresponding value-weighted sum of S&P 100 or S&P 500 stocks’ risk-neutralvariance computed from individual firm equity options. The data is daily from January 1996 to October 2014.

Panel A. S&P 100, one-month horizon

SV

IXt2

SV

IXt2

0.2

0.4

0.6

0.8

1.0

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

Panel C. S&P 500, one-month horizon

SV

IXt2

SV

IXt2

0.2

0.4

0.6

0.8

1.0

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

Panel B. S&P 100, one-year horizon

SV

IXt2

SV

IXt2

0.2

0.4

0.6

0.8

1.0

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Feb/14

Panel D. S&P 500, one-year horizon

SV

IXt2

SV

IXt2

0.2

0.4

0.6

0.8

1.0

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

Internet Appendix – 19

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Figure IA.3: Beta, size, value, momentum, and option-implied equity variance

This Figure reports (equally-weighted) averages of risk-neutral stock variance (SVIX2i,t, computed from individual

firm equity options) of S&P 500 stocks, conditional on firm beta, size, book-to-market, and momentum. At everydate t, we assign stocks to decile portfolios based on on their characteristics and report the time-series averages ofSVIX2

i,t across deciles. The horizon is one month. The sample period is January 1996 to October 2014.

Panel A. Beta

High P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Low

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Panel B. Size

Small P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Big

0.00

0.05

0.10

0.15

0.20

0.25

Panel C. Book-to-market

Value P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Growth

0.00

0.05

0.10

0.15

0.20

0.25

Panel D. Momentum

Winner P.2 P.3 P.4 P.5 P.6 P.7 P.8 P.9 Loser

0.00

0.05

0.10

0.15

0.20

0.25

Internet Appendix – 20

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Figure IA.4: Beta, size, value, momentum, and option-implied equity variance

This Figure plots the time-series of risk-neutral stock variance (SVIX2i,t, computed from individual firm equity

options) of S&P 500 stocks, conditional on firm beta, size, book-to-market, and momentum. At each date t, weclassify firms as small, medium, or big when their market capitalization is in the bottom, middle, or top tertile ofthe time-t distribution across all firms in our sample, and compute the (equally-weighted) average of SVIX2

i,t. Weclassify firms by other characteristics at time t in a similar way. The horizon is monthly. The sample period isfrom January 1996 to October 2014.

Panel A. Beta

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

0.8

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

HighMediumLow

Panel C. Book-to-market

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

ValueNeutralGrowth

Panel B. Size

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

SmallMediumBig

Panel D. Momentum

Sto

ck v

aria

nce

0.0

0.2

0.4

0.6

0.8

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11 Jan/14

WinnerNeutralLoser

Internet Appendix – 21

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Figure IA.5: Size, value, and option-implied equity variance

This Figure plots the time-series of risk-neutral stock variance (SVIX2i,t, computed from individual firm equity

options) of S&P 500 stocks, conditional on firm size and book-to-market. At each date t, we classify firms as small,medium, or big when their market capitalization is in the bottom, middle, or top tertile of the time-t distributionacross all firms in our sample, and compute the (equally-weighted) average of SVIX2

i,t. Similarly, we classify firmsas value, neutral, or growth stocks when their book-to-market ratio is within the top, middle, or bottom tertile ofthe book-to-market distribution at time t. Panels A and B plot the time-series of SVIX2

i,t-averages for intersectionsof size and value tertiles. The horizon is annual. The sample period is from January 1996 to October 2014.

Panel A. Small stocks

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

Small ValueSmall Growth

Panel B. Big stocks

Sto

ck v

aria

nce

0.0

0.1

0.2

0.3

0.4

0.5

0.6

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

Big ValueBig Growth

Internet Appendix – 22

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Figure IA.6: Principal component analysis of unexpected portfolio returns

This Figure plots the first four principal components of unexpected returns in excess of the market. The returnhorizon is one year and data is sampled at a monthly frequency. Every month from January 1996 to October2014, we sort all available S&P 500 firms into 100 portfolios based on their SVIXi,t and consider three alternativedefinitions of unexpected returns: the residuals computed using the pooled regressions, as in equation (20); residualscomputed using the panel regressions with fixed effects, as in equation (21); and residuals computed using the modelwith coefficients constrained by theory, as in equation (16). In the plot legends, we report the residual varianceexplained by each of the principal components.

PC1

−3

−2

−1

01

23

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.279)fixed effects (0.294)theory (0.279)

PC2

−3

−2

−1

01

2

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.167)fixed effects (0.144)theory (0.169)

PC3

−2

−1

01

2

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.043)fixed effects (0.044)theory (0.043)

PC4

−1.

5−

1.0

−0.

50.

00.

51.

0

Jan/96 Jan/99 Jan/02 Jan/05 Jan/08 Jan/11

pooled (0.028)fixed effects (0.029)theory (0.028)

Internet Appendix – 23

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Figure IA.7: Performance Fees with Monthly Rebalancing

This Figure summarizes the performance of portfolios based on model-implied expected excess returnsrelative to the market benchmark (a value-weighted portfolio) and a naive diversification strategy (anequally-weighted portfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for short

positions, and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1. The

parameter θ controls the aggressiveness of the strategy; we set θ = 1 in Panel A and θ = 2 in Panel B.We report performance fees (following Fleming et al., 2001) that a risk-averse investor with relativerisk aversion ρ = 3 would be willing to pay to switch from the value-weighted benchmark (on the left)or equally-weighted benchmark (on the right) to the model portfolio. Expected returns are based onfirms’ one-year SVIXi,t and we rebalance portfolios on a monthly basis. Using monthly data fromJanuary 1996 to October 2014, we obtain the distribution of performance fees from the block bootstrapprocedure described in Appendix B.

Panel A. Aggressiveness parameter θ = 1

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.045 0.955 Mean: 4.2%Median: 4.2%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

075

0.15

00.

225

0.30

0

Fre

quen

cy

0.182 0.818 Mean: 1.1%Median: 1.1%

Panel B. Aggressiveness parameter θ = 2

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.038 0.962 Mean: 4.9%Median: 4.7%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

075

0.15

00.

225

Fre

quen

cy

0.202 0.798 Mean: 1.8%Median: 1.7%

Internet Appendix – 24

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Figure IA.8: Performance Fees with Daily Rebalancing

This Figure summarizes the performance of portfolios based on model-implied expected excess returnsrelative to the market benchmark (a value-weighted portfolio) and a naive diversification strategy (anequally-weighted portfolio). For the model portfolio, we apply a rank weighting scheme,

wXSi,t =rank[EtRi,t+1]θ∑i rank[EtRi,t+1]θ

,

which assigns portfolio weights wXSi,t that increase in expected excess returns, does not allow for

short positions, and ensures that the investor is fully invested in the stock market, i.e.∑i w

XSi,t = 1.

The parameter θ controls the aggressiveness of the strategy; we set θ = 1 in Panel A and θ = 2 inPanel B. We report performance fees (following Fleming et al., 2001) that a risk-averse investor withrelative risk aversion ρ = 3 would be willing to pay to switch from the value-weighted benchmark(on the left) or equally-weighted benchmark (on the right) to the model portfolio. Expected returnsare based on firms’ one-year SVIXi,t and we rebalance portfolios on a daily basis. Using daily datafrom January 1996 to October 2014, we obtain the distribution of performance fees from the blockbootstrap procedure described in Appendix B.

Panel A. Aggressiveness parameter θ = 1

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.045 0.955 Mean: 4.1%Median: 4.1%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

100

0.20

00.

300

Fre

quen

cy

0.224 0.776 Mean: 0.9%Median: 1.0%

Panel B. Aggressiveness parameter θ = 2

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.070 0.930 Mean: 4.4%Median: 4.4%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

075

0.15

00.

225

Fre

quen

cy

0.272 0.728 Mean: 1.3%Median: 1.3%

Internet Appendix – 25

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Figure IA.9: Performance Fees in Small vs Big and Value vs Growth Firm Portfolios

This Figure reports the bootstrap distribution of performance fees that a risk-averse investor (ρ = 3)would be willing to pay to switch from the value-weighted benchmark (on the left) or equally-weightedbenchmark (on the right) to the model portfolio. We rebalance portfolios on a daily basis and setthe aggressiveness parameter θ = 2; for details, see the description for Figure IA.8. We report resultsfor implementing the strategy with stocks of small and big firms (in the bottom/top tertile of themarket capitalization distribution at the beginning of the month) and value and growth firms (in thetop/bottom tertile of book-to-market distribution at the beginning of the month).

Panel A. Small Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.002 0.998 Mean: 7.9%Median: 7.8%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.016 0.984 Mean: 5.3%Median: 5.2%

Panel B. Big Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.198 0.802 Mean: 2.0%Median: 2.1%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.345 0.655 Mean: 0.9%Median: 1.0%

Panel C. Value Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.004 0.996 Mean: 9.0%Median: 8.9%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.005 0.995 Mean: 5.1%Median: 5.0%

Panel D. Growth Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.085 0.915 Mean: 4.2%Median: 4.2%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.211 0.789 Mean: 1.7%Median: 1.7%

Internet Appendix – 26

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Figure IA.10: Performance Fees in Size-/Book-to-Market Portfolios

This Figure reports the bootstrap distribution of performance fees that a risk-averse investor (ρ = 3)would be willing to pay to switch from the value-weighted benchmark (on the left) or equally-weightedbenchmark (on the right) to the model portfolio. We rebalance portfolios on a daily basis and setthe aggressiveness parameter θ = 2; for details, see the description for Figure IA.8. We report resultsfor implementing the strategy with small/value, small/growth, big/value, and big/growth stocks. Weclassify firms based on a 3 × 3 conditional double sort on market capitalization and book-to-marketratios at the beginning of the month.

Panel A. Small Value Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

0

Fre

quen

cy

0.001 0.999 Mean: 11.6%Median: 11.3%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.003 0.997 Mean: 8.2%Median: 7.9%

Panel B. Small Growth Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.025 0.975 Mean: 6.1%Median: 6.0%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.064 0.936 Mean: 4.0%Median: 4.0%

Panel C. Big Value Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

0.20

0

Fre

quen

cy

0.292 0.708 Mean: 1.3%Median: 1.3%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

075

0.15

00.

225

Fre

quen

cy

0.450 0.550 Mean: 0.3%Median: 0.3%

Panel D. Big Growth Firms

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to VW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.311 0.689 Mean: 1.5%Median: 1.6%

−10% −5% 0% 5% 10% 15% 20% 25%

Performance fee relative to EW portfolio (p.a.)

0.00

00.

050

0.10

00.

150

Fre

quen

cy

0.303 0.697 Mean: 1.4%Median: 1.3%

Internet Appendix – 27

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Figure IA.11: Finite-sample properties of the block bootstrap procedure

To provide evidence for the reliability of our bootstrap procedure in finite samples, we simulateS = 200 samples on which we impose the null hypothesis (α = 0 and γ = 0.5) and within eachsample we repeat the bootstrap procedure described in Appendix B.1 with B = 99 iterations.We present results for one-year excess market returns of S&P 100 firms, sampled at a monthlyfrequency. In Panel A, we compare the empirical quantiles of the Wald statistic in the simulateddata to the quantiles of the Wald statistic’s asymptotic χ2-distribution. In Panel B, we comparethe rejection frequency for the null hypothesis in the simulated data (on which we imposed thenull hypothesis) to the nominal size of the test. The big circle with cross indicates the p-valueof 0.437 we obtain from applying the bootstrap procedure to the empirical data, as reported inPanel A of Table 4.

Panel A: Empirical and asymptotic quantiles of the Wald statistic

0 2 4 6 8 10

05

1015

2025

Horizon: 12 months, S = 200, B = 99

Quantiles of χ2−distribution

Em

piric

al q

uant

iles

90% quantile95% quantile99% quantile

Panel B: Nominal size and empirical rejection frequencies

Horizon: 12 months, S = 200, B = 99

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Internet Appendix – 28

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Figure IA.12: Empirical and asymptotic quantiles of the Wald statistic

To provide evidence for the reliability of our bootstrap procedure in finite samples, we simulate S = 200 sampleson which we impose the null hypothesis (α = 0 and γ = 0.5) and within each sample we repeat the bootstrapprocedure described in Appendix B.1 with B = 99 iterations. We present results for one-, three-, six-, and 24-month excess market returns of S&P 100 firms, sampled at a monthly frequency. For each horizon, wee compare theempirical quantiles of the Wald statistic in the simulated data to the quantiles of the Wald statistic’s asymptoticχ2-distribution.

0 2 4 6 8 10

05

1015

2025

Horizon: 1 months, S = 200, B = 99

Quantiles of χ2−distribution

Em

piric

al q

uant

iles

90% quantile95% quantile99% quantile

0 2 4 6 8 10

05

1015

2025

Horizon: 3 months, S = 200, B = 99

Quantiles of χ2−distribution

Em

piric

al q

uant

iles

90% quantile95% quantile99% quantile

0 2 4 6 8 10

05

1015

2025

Horizon: 6 months, S = 200, B = 99

Quantiles of χ2−distribution

Em

piric

al q

uant

iles

90% quantile95% quantile99% quantile

0 2 4 6 8 10

05

1015

2025

Horizon: 24 months, S = 200, B = 99

Quantiles of χ2−distribution

Em

piric

al q

uant

iles

90% quantile95% quantile99% quantile

Internet Appendix – 29

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Figure IA.13: Nominal size and empirical rejection frequencies

To provide evidence for the reliability of our bootstrap procedure in finite samples, we simulate S = 200 samples onwhich we impose the null hypothesis (α = 0 and γ = 0.5) and within each sample we repeat the bootstrap proceduredescribed in Appendix B.1 with B = 99 iterations. We present results for one-, three-, six-, and 24-month excessmarket returns of S&P 100 firms, sampled at a monthly frequency. For each horizon, we compare the rejectionfrequency for the null hypothesis in the simulated data (on which we imposed the null hypothesis) to the nominalsize of the test. The big circles with crosses indicates the p-value we obtain from applying the bootstrap procedureto the empirical data, as reported in Panel A of Table 4: 0.841 at the one-month horizon, 0.832 at the three-monthhorizon, 0.609 at the six-month horizon, and 0.439 at the 24-month horizon.

Horizon: 1 months, S = 200, B = 99

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 3 months, S = 200, B = 99

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 6 months, S = 200, B = 99

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 24 months, S = 200, B = 99

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

0.2

0.4

0.6

0.8

1

Internet Appendix – 30

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Figure IA.14: Nominal size and empirical rejection frequencies (S = 400, B = 198)

To provide evidence for the reliability of our bootstrap procedure in finite samples, we simulate S = 400 sampleson which we impose the null hypothesis (α = 0 and γ = 0.5) and within each sample we repeat the bootstrapprocedure described in Appendix B.1 with B = 198 iterations. We present results for one-, three-, six-, 12- and24-month excess market returns of S&P 100 firms, sampled at a monthly frequency. For each horizon, we comparethe rejection frequency for the null hypothesis in the simulated data (on which we imposed the null hypothesis)to the nominal size of the test. The big circles with crosses indicates the p-value we obtain from applying thebootstrap procedure to the empirical data, as reported in Panel A of Table 4: 0.841 at the one-month horizon,0.832 at the three-month horizon, 0.609 at the six-month horizon, 0.437 at the 12-month horizon, and 0.439 at the24-month horizon.

Horizon: 1 months, S = 400, B = 198

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 3 months, S = 400, B = 198

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 6 months, S = 400, B = 198

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 12 months, S = 400, B = 198

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Horizon: 24 months, S = 400, B = 198

Nominal size

Em

piric

al r

ejec

tion

freq

uenc

y

0 0.2 0.4 0.6 0.8 1

00.

20.

40.

60.

81

Internet Appendix – 31

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Figure IA.15: Beta Linearization and Approximation Errors

The figures below proxy var∗t (Rg,t+1/Rf,t+1) by var∗t (Rm,t+1/Rf,t+1) and use equation (7) to compute a firm’s

implied beta as β∗i,t = 1 + 12 (SVIX2

i,t−SVIX2

t )/SVIX2t so that, from equation (IA.A.5), approximation error =

− 12 SVIX2

t [(β∗i,t − 1)2 −

∑j wj,t(β

∗j,t − 1)2]. We compute implied betas and approximation errors for all S&P 100

and S&P 500 firms each month from January 1996 to October 2014 for horizons of one, three, six, 12, and 24months. Panel A reports results for squared deviations of betas from one. Panel B illustrates approximation errorsin a range of plus/minus 2.5% p.a.

Panel A. Beta deviations

●●

●● ● ●

0.0

0.2

0.4

0.6

0.8

1.0 S&P 100

(βi,t − 1)2

Cum

ulat

ive

rela

tive

freq

uenc

ies

● 30 days91 days182 days365 days730 days

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

●●

●●

●● ●

0.0

0.2

0.4

0.6

0.8

1.0 S&P 500

(βi,t − 1)2

Cum

ulat

ive

rela

tive

freq

uenc

ies

● 30 days91 days182 days365 days730 days

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Panel B. Approximation errors

● ● ● ● ● ● ● ●●

● ●●

● ● ●

0.00

0.05

0.10

0.15

0.20

0.25

0.30

S&P 100

Approximation error (% p.a.)

Rel

ativ

e fr

eque

ncie

s

● 30 days (cum: 0.840)91 days (cum: 0.874)182 days (cum: 0.896)365 days (cum: 0.911)730 days (cum: 0.917)

−2.5 −2 −1.5 −1 −0.5 0 0.5 1 1.5 2 2.5

● ● ● ● ● ● ● ●●

●● ● ●

0.00

0.05

0.10

0.15

0.20

S&P 500

Approximation error (% p.a.)

Rel

ativ

e fr

eque

ncie

s

● 30 days (cum: 0.716)91 days (cum: 0.759)182 days (cum: 0.786)365 days (cum: 0.794)730 days (cum: 0.782)

−2.5 −2 −1.5 −1 −0.5 0 0.5 1 1.5 2 2.5

32