Upload
tomkacy
View
176
Download
0
Tags:
Embed Size (px)
Citation preview
Risk ManagementUniversity of Economics, Kraków, 2012
Tomasz Aleksandrowicz
market risk management
techniques: hedging & diversificationmeasuring market risk
derivatives summary matrix
risk category options futures forwards swaps
equity stock option index future (e.g. DIJA)
repo (repurchase agreement) equity swap
interest rate e.g. basis swap e.g. Euribor future
FRA (forward rate agreement)
interest rate swap
foreign exchange FX option FX future FX forward FX swap
commodity e.g. gold option e.g. weather derivatives forward contract commodity swap
hedging
hedging
• protects assets against unfavourable movements in value of the underlying asset
• investment position intended to offset potential losses of organization’s financial exposures
• it is to reduce the volatility of the asset value changes / cash flow
• using assets that have negative or weak correlation• using derivatives and/or short selling
correlation
• known as the correlation coefficient• ranges between -1 and +1, where:– -1 - perfect negative correlation - two securities moves
opposite direction– 0 - no correlation (random relation)– +1 - perfect positive correlation - two securities moves
same direction
• perfectly correlated securities are rare, rather some degree of correlation
correlation table (example)
Google Microsoft Ford Motor AT&T
JP Morgan Chase
Merck & Inc.
Exxon Mobile
Walt Disney
Google 0.26 0.35 0.4 0.64 0.06 0.16 0.34
Microsoft 0.26 0.57 0.35 0.61 0.34 0.83 0.79
Ford Motor 0.35 0.57 0.62 0.61 0.28 0.72 0.62
AT&T 0.4 0.35 0.62 0.55 0.39 0.6 0.58
JP Morgan Chase
0.64 0.61 0.61 0.55 0.43 0.73 0.68
Merck & Inc. 0.06 0.34 0.28 0.39 0.43 0.5 0.54
Exxon Mobile 0.16 0.83 0.72 0.6 0.73 0.5 0.8
Walt Disney 0.34 0.79 0.62 0.58 0.68 0.54 0.8
basic hedging methods
• pair of stock with negative correlation• derivatives (options, features/forwards, swaps, etc.)• short selling
8
short selling
• difference: long position and short position• short selling is selling of borrowed assets• profit is difference between price at borrow date and
price of re-purchase• short selling is widely treated as speculative
technique• short selling is regulated by financial regulators
9
example 1: stock A onlydate investment quantity price value total value of
investment
start day stock A 100 100 10,000 10,000
next day up stock A 100 105 10,500 10,500
next day down
stock A 100 95 9,500 9,500
example 2: stock A hedge by stock Bwith negative correlation of stock B (-0,4)
date investment quantity price value total value of investment
start day stock A 50 100 5,000 10,000
start day stock B (-0.4) 100 50 5,000
next day up stock A 50 105 5,250 10,150
next day up stock B (-0.4) 100 49 4,900
next day down
stock A 50 95 4,750 9850
next day down
stock B (-0.4) 100 51 5,100
example 3: stock A put option hedgeput (sell) option at price of 100
date investment quantity price value total value of investment
start day stock A 99 100 9,900 9,999
start day put option A (100)
99 1 99
next day up stock A 99 105 10,395 10,395
next day up put option A (100)
100 0 0
next day down
stock A 99 95 9,405 9,900
next day down
put option A (100)
99 5 495
example 4: stock A hedge short sellshort selling of stock B with positive correlation (0,8)
date investment quantity price value total value of investment
start day stock A 50 100 5,000 10,000
start day short stock C (0.8)
100 50 5,000
next day up stock A 50 105 5,250 10,050
next day up short stock C (0.8)
100 48 4,800
next day down
stock A 50 95 4,750 9,950
next day down
short stock C (0.8)
100 52 5,200
hedging strategies output summary
strategy start value of investment
value next day up value next day down
stock A only 10,000 10,500 9,500
stock A + stock B (-0.2) 10,000 10,150 9,850
stock A + put option A 9,999 10,395 9,900
stock A + short stock C (0,8) 10,000 10,050 9,950
hedging issues
• precise calculation and smart decisions needed• brokerage fees and commissions (additional costs)• complexity of the derivatives – risk of
misunderstanding or misconduct• complexities associated with the tax and accounting
consequences• combined with leverage is so-called ‘weapon of mass
destruction
15
diversification
diversification
• diversification means reducing risk by investing in a variety of assets (within one or more asset class)
• it means: don't put all your eggs in one basket• diversified portfolio will have less risk than the
weighted average risk of its elements• often less risk than the least risky of its parts• crucial element is selection of assets with low
correlation
17
specific and systematic risk
• difference: specific risk and systematic risk• individual, specific securities are much more risky
than the market• specific risk can be lowered by diversification• systematic risk is a limit for diversification efficiency –
can not be eliminated by diversification
18
diversification and risk
19
measurement of specific risk
• specicfic risk could be measured by standard deviation (SD)• SD tells how far a set of numbers are spread out from each
other (from mean/expected value)• standard deviation (sq root ov variance):
20
long-run historical return and SD
Avg. Return SDSmall Stocks 17.5% 33.1%Large Co. Stocks 12.4% 20.3%L-T Corp Bonds6.2% 8.6%L-T Govt. Bonds 5.8% 9.3%U.S. T-Bills 3.8% 3.1%
based on 80yr data (1926-2004)
21
measurement of systematic risk
• can be measured as the sensitivity of a stock’s return to fluctuations in returns on the market portfolio
• is measured by the beta coefficient, or β.
22
b = % change in asset return
% change in market return
Beta factor interpretation
• if = 0b– asset is risk free
• if = 1b– asset return = market return
• if > 1b– asset is riskier than market index
• if < 1b– asset is less risky than market index
23
Beta factor sample
24
stock bGoogle 1.19
Microsoft 1.00
Ford Motor 2.92
AT&T 0.46
JP Morgan Chase 1.66
Merck & Inc. 0.30
Exxon Mobile 0.61
Walt Disney 1.37
example: two assets portfolio
25
example: two assets portfolio
26
example: two assets portfoliostart price Mon Tue Wed Thu Fri SD
stock A (100% - 100 shares) 100 105 110 112 108 103
portfolio value 10000 10500 11000 11200 10800 10300 3.6469
stock B (100% - 200 shares) 50 52 53 52 53 54
portfolio value 10000 10400 10600 10400 10600 10800 0.8367
start price Mon Tue Wed Thu Fri SD
stock A (50% - 50 shares) 100 105 110 112 108 103
stock B (50% - 100 shares) 50 52 53 52 53 54
portfolio value 10000 10450 10800 10800 10700 10550 2.2418
modern portfolio theory
• portfolio - collection of securities that together provide an investor with an attractive trade-off between risk and return
• portfolio theory - concept of making security choices based on portfolio expected returns and risks (risk-return trade-off)
• capital asset pricing model (CAPM) and many other mathematical models and concepts used for portfolio management
28
portfolio creation process
29
portfolio types
• market portfolio – all tradable assets on market• main index portfolio – all index assets (e.g. DIJA)• efficient portfolio – where:– maximum expected return for a given level of risk– minimum risk for a given expected return
• zero-risk portfolio - constant low-return portfolio with no risk
30
measuring risk: value at risk
VaR (I)
• Market risk not much in Basel II scope• VaR (Value-at-Risk) – standard market risk method• In its simplest form: market VAR takes the banks’s
market risks and estimates how much they might lose over a given time period
• Example: if bank has a one-day, 99% VaR of $50 million, then 99 days out of 100 it should not expect to lose more than $50 million.
33
VaR (II)
• The volatility of the underlying asset– e.g. equity or bond price, currency rate
• A matrix of correlations– e.g. the historical price relationships between equities, interest rates,
currencies, credit spreads, and so on);
• A liquidation period – e.g. one day, one week, one month or however long a firm thinks it
will take to unwind or neutralize its risk
• A statistical confidence level – e.g. 95% or 99%
34
VaR problems
• VAR does not tell how big the loss might be on the 100th day
• it is based on historical correlations which can break down in times of market stress,
• it is based on statistical assumptions (which may or may not become true)
• VAR can really only be used for marked-to-market portfolios (revalued every day)
35