Tienoven, Thornas-Jelle Van - The Influence of Pricing Differences on the Application of European-style Asion Options, A Liturature Study

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    Bachelor Thesis Finance, June 2007

    THE INFLUENCE OF PRICING DIFFERENCES ON THE

    APPLICATION OF EUROPEAN-STYLE ASIAN

    OPTIONS: A LITERATURE STUDY

    Thomas-Jelle van Tienoven,

    272411

    [email protected]

    Supervisor:

    Jiajia Cui

    Finance Department, K9.34

    Tilburg University

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    Abstract

    In this thesis I investigate how the complexity of pricing Asian options could make a

    difference in applying the options in line with determined trading objectives. In thecomprehensive literature on pricing methods of European-style Asian options I

    simplify the Monte Carlo Simulation Approach to a basic concept and compare this to

    the Black-Scholes Option Pricing Model for European vanilla options. Subsequently I

    discuss practical examples on the application of European-style Asian options and

    make a distinction between stand-alone trades and embedment in financial contracts.

    Accordingly, I find that in certain situations institutional and individual investors

    prefer the complex structure of Asian like payoff diagrams and conclude that in these

    cases the pricing differences between European vanilla options and European-style

    Asian options play a significant role in setting preferences for the application of these

    options to achieve determined trading objectives.

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    Table of contents

    1. Introduction............................................................................................................03

    2. Background ............................................................................................................05

    * 2.1 Trading objectives..............................................................................................05

    * 2.2 Derivatives markets ...........................................................................................06

    * 2.3 Options markets .................................................................................................06

    * 2.4 European vanilla stock options ..........................................................................07

    * 2.5 European-style Asian options ............................................................................10

    3. Pricing methods......................................................................................................13

    * 3.1 The Black-Scholes Option Pricing Model .........................................................13

    * 3.2 The Monte Carlo Simulation Approach.............................................................14

    4. The application of European-style Asian options ...............................................18

    * 4.1 Stand-alone trades ..............................................................................................18

    * 4.2 Embedment in financial contracts......................................................................19

    5. Conclusion and recommendation .........................................................................21

    * 5.1 Conclusion .........................................................................................................21

    * 5.2 Recommendation ...............................................................................................22

    * 5.3 Acknowledgement .............................................................................................22

    References ...................................................................................................................23

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    1. Introduction

    Asian options are commonly traded on currencies and commodity products

    with low trading volume. End-users of commodities or energies tend to be exposed toaverage price over time, so Asian options are attractive for them. Asian options are

    also popular with corporations, such as exporters, who have ongoing currency

    exposures (Contingency Analysis, 1996). Asian options are also attractive because

    they tend to be less expensive than comparable vanilla options. This is because the

    volatility in the average value of an underlying asset is lower than the volatility of the

    current value of the underlying asset at maturity.

    In situations where the underlying asset is thinly traded or there is the potential

    for its price to be manipulated, an Asian option offers protection. It is more difficult to

    manipulate the average value over an extended period of time than it is to manipulate

    it just at expiration. The longer the holding period of the option in which the average

    price of the underlying asset is influenced, the more the investor is protected for price

    manipulation.

    Asian options are often used as they more closely replicate the requirements of

    firms exposed to price movements on the underlying asset. For example, an airline

    might purchase a one year Asian call option on fuel to hedge its fuel costs

    (vDerivatives, 2005). In order to minimize the volatility on the market price for fuel,

    the airline would prefer to hold an Asian option based on the average market rate of

    fuel rather than an option that is based on as single strike price.

    The lower prices of Asian options relative to European options make them

    useful for situations in which the user wants to hedge or speculate on the price series

    but is unwilling to spend the full price required by European options. So Asian

    options are cash flow reducing. Moreover, this type of option is mainly used in

    markets where prices are unusually volatile commodities like crude oil, natural gas,

    copper, aluminum (Overseas Development Institute, 1995) and may be susceptible

    to distortion or manipulation. For example, Denali Consulting (2005) outlines the

    urge for managers to maintain focus on substantial price swings related to increase in

    demand or shortage in supply.

    Furthermore, next to the abovementioned examples on stand-alone Asian

    options, which are traded in the OTC market, Asian options also exist as parts of

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    financial contracts. Life insurance contracts for example may be in need to guarantee

    a minimum rate of return being the average of the past returns. For further reading

    hereupon, see Jiajia Cui, Pricing Interest Rate Guarantees embedded in Life

    Insurance Contracts by Monte Carlo Simulation, MSc thesis, University of

    Amsterdam, Amsterdam, The Netherlands, August 2003.

    These abovementioned examples underline the need for guidance in trading

    objectives on whether to use European-style Asian options compared to European

    vanilla options. The aim of this thesis is to provide an overview on these two types of

    options, how they are generally priced and valuated and the differences herein,

    leading two the research question:How can valuation and pricing differences between

    European vanilla options and European-style Asian options play a role in applying

    these options in line with determined trading objectives?

    First, I will briefly outline the two major trading objectives and introduce the

    derivatives market and options market respectively. Subsequently I summarize both

    types of options focused upon, that is European vanilla options and European-style

    Asian options. Next, I will go deeper into pricing and valuation methods on the two

    option types and on the basis of this overview I discuss the application of European-

    style Asian options in contrast to European vanilla options.

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    2. Background

    2.1 Trading objectives

    Any investor whether institutional or an individual needs to set objectivesbefore he or she actually starts with making investment decisions. There is no perfect

    investment process, but the Association for Investment Management and Research

    (AIMR) suggests following its basic framework. The first step in this framework is to

    set objectives. Such objectives center on the risk-return trade-off between return

    requirements and risk tolerance.

    On the one hand an investor can require a high rate of return on his or her

    investment, but logically this is partially involved with a higher level of risk compared

    to an investor that requires a less high rate of return. For instance, individual investors

    that have a high level of risk tolerance can invest in a way of arbitraging.

    Arbitrage opportunities arise when two or more securities are mispriced

    relative to each other. If such a scenario occurs, an investor can take a long position in

    one derivative and sell short another related derivative. For instance, if the price of a

    European put option exceeds the value predicted by put-call parity, an investor can

    make use of this arbitrage opportunity by selling short the overpriced put, take a long

    position in the related call, sell short the underlying asset and take a long position in

    risk-free securities, like bonds. The payoff diagram for the arbitrageur will look like

    this:

    S(T) < X X S(T)

    short put - (X - S(T)) 0

    long call 0 S(T) - X

    short stock - S(T) - S(T)

    long bond X X

    0 0

    In both states of outcome, that is whether the price of the underlying asset at

    maturity is lower or higher than the exercise price, the payoff will be zero. But since

    the put is overpriced, it will gain more money than the replication with a long call.

    Creating the profit from this mispricing is called an arbitrage opportunity.

    On the other hand an investor can focus on risk reduction by investing in a

    financial position contrary on the position that he or she currently is in. This is

    commonly done by institutional investors, like companies. Reducing risk by taking an

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    opposite position is moreover known as hedging. It is an extreme case of

    diversification, in which negative correlation between two risks is involved. Financial

    risk can be reduced by buying and selling derivative securities. If an investor holds a

    position in 1,000 Microsoft shares for instance, he or she can hedge this by buying put

    options on Microsoft. In case the stock prices increase over the time, the gain

    hereupon is relatively lowered by the put premium paid. But more strongly, in case

    the stock price decreases over the time, the loss hereupon is reduced by the payoff on

    the put options. In other words, the financial risk is reduced and the position is so-

    called hedged.

    2.2 Derivatives markets

    Derivatives exist to transfer risks from those who do not want to bear it to

    those who do (Marthinsen, 2005). These are financial instruments whose returns are

    derived from those of other financial instruments. Derivatives are contractual

    instruments whose performance is determined by how an underlying asset or

    instrument performs. While derivatives can be powerful speculative instruments,

    businesses most often use them to hedge in order to protect themselves against shocks

    in currency values, commodity prices and interest rates for example. At the end of

    June 2004 the Bank for International Settlements (2007) recorded a total notional

    amount of all the outstanding positions in the derivatives market of $220 trillion. This

    trading volume underlines the importance of financial derivatives.

    Derivatives come roughly in two basic categories: option-type contracts and

    forward-type contracts. These may be exchange-listed, such as futures and stock

    options, or they may be privately traded. The major difference between the two basic

    categories is explained by the right to exercise an option or the obligation to execute

    the contract at delivery date. This thesis deals with financial instruments in the options

    market.

    2.3 Options markets

    The options markets have been tremendously successful, reflected by the

    heavy trading volume in these markets for example the Chicago Board Options

    Exchange (2007) announced a volume of 674,735,348 option contracts over 2006.

    Options are derivative instruments that entail a contract between two parties

    a buyer and a seller. It gives the buyer the right to purchase or sell something at a later

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    date agreed at a todays settled price. Options exist on financial assets, like stocks and

    bonds, but also on commodities, futures contracts and foreign currencies. Most of

    these types of options are traded on exchange-listed basis. However, the over-the-

    counter market, a market in which option trading is conducted privately between two

    parties who prefer rather contracting with each other than to a public transaction, has

    been revived and is now very large and widely used by corporations and financial

    institutions.

    A wide variety of options exist, but generally they can be divided into two

    main categories. The payoff for path-independent options is not affected by the

    sequence of prices of the underlying asset as it moves towards the expiration of the

    option. In other words, the average price over time of the underlying asset does not

    influence the payoff of the option. In contrast, path-dependent options are affected by

    the price fluctuation of the underlying asset over the holding period of the option

    (Chance, 2004).

    Recently, customized options have been made available to investors. Now

    innovation still occurs in the market for customized options that are not exchange-

    listed (Bodie, Kane and Marcus, 2005). The path-dependent exotic option I am going

    to deal with in this thesis is the Asian option.

    In order to be able to answer the conducted research question I will elaborate

    on differences between this European-style Asian stock option and the European

    vanilla stock option. Hereby I assume the options to be written on non-dividend

    paying stocks. Differences in these two stock options can be found in both the payoff

    construction and the valuation method.

    2.4 European vanilla stock options

    European vanilla stock options give its holders the right to sell or buy the

    underlying asset for a specified price, called the strike price, on some specified

    expiration date.

    The term European does not refer to geographic regions of these options or

    their underlying assets. It is confined to the possibility to exercise an option only at

    maturity, in contrast to so-called American options, which can be exercised prior to

    the expiration date.

    In general, this type of option can be divided into call options and put options.

    A call gives the right to buy the underlying; a put option gives the right to sell. The

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    holder of a European call is not required to exercise the right to buy. He or she will

    only choose to do so if the market value of the asset to be purchased exceeds the

    strike price at the end of the holding period. If the call is left unexercised, it will be

    worthless. Since the holder cannot be forced to exercise the option, the minimum

    value of a European call therefore is:

    0eC

    Logically, no one would pay more for the right to buy a stock than for the stock itself.

    Therefore the maximum value of a European call is:

    0SCe

    In case the call is exercised, the value will be the difference between the stock price at

    expiration and the strike price. The mathematical way of presenting the value of a

    European call at expiration is as follows:

    ),0( XSMAXCTe=

    But more strongly, what is important is the value of the European call prior to

    expiration. The price of a European call must at least equal the greater of zero or the

    stock price minus the present value of the exercise price. If this is not the case,

    arbitrage opportunities arise, like aforementioned. An investor could then buy the call

    and invest in risk-free bonds and take a short position in the stock. Since the

    combination of buying a call and risk-free bonds is less then the stock sold short, one

    has a positive initial cash flow. At maturity of the call, again, the exercise price can be

    higher than the stock price, of which the difference would lead to another positive

    cash flow. If the exercise price turns out to be lower, then there would be no cash flow

    at maturity. In other words, if the following lower bound for pricing a European call

    would not hold, investors would have the opportunity the gain money from a risk-free

    position:

    ))1(,0( 0T

    e rXSMAXC

    +

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    Similar equations holds for European put options. A holder of a European put

    has the right to sell the underlying asset for a specified price, called the strike price,

    on some specified expiration date. Since this is not obligatory the put holder will only

    do so if exercising provides a positive cash flow. Therefore the minimum value of a

    put is:

    0eP

    An investor that holds European puts expects the price of the underlying asset to

    decrease. If the stock price is lower than the exercise price the put holder will have a

    positive cash flow, because he or she can short sell the stock for the exercise price and

    buy back the stock for the current price. So the gain from a European put is the

    difference between the strike price and the stock price at maturity. The mathematical

    way of presenting the value of a European put at expiration is as follows:

    ),0(Te

    SXMAXP =

    The best case scenario for a put holder is when the company that has written the put

    goes bankrupt. Then the stock at maturity is worth zero and the put holder earns the

    strike price (minus the premium paid to buy the right to sell). The maximum value of

    a European put therefore is the present value, discounted for interest rate r, of the

    strike price:

    T

    erXP + )1(

    Subsequently, the value of a European put must always at least equal the greater of

    zero or the present value of the strike price minus the stock price. Otherwise arbitrage

    opportunities arise. An investor could then sell short the put, borrow money the

    present value of the strike price X, and buy the stock. This generates an initial positive

    cash flow as buying the stock is less than selling short the put and borrow money

    equivalent to the discounted strike price. At maturity of the put, the stock price could

    be lower than the exercise price, what leads to another positive cash flow. If the stock

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    price turns out to be higher than the exercise price, there would be no cash flow at

    maturity. In conclusion, if the following lower bound for pricing a European put

    would not hold, investors would have the opportunity the gain money from a risk-free

    position:

    ))1(,0( 0SrXMAXPT

    e +

    For further reading on European vanilla stock options, see John C. Hull, Options,

    Futures and other Derivatives, 6th edition, 2006, chapter 9.

    2.5 European-style Asian stock options

    Asian options are options where the payoff depends on the average price of the

    underlying asset during at least some part of the life of the option (Hull, 2006).

    Because of this fact, Asian options have a lower volatility and hence rendering them

    cheaper relative to their European counterparts. They are commonly traded on

    currencies and commodity products which have low trading volumes. Asian options

    were originally used in 1987 when Banker's Trust Tokyo office used them for pricing

    average options on crude oil contracts (Global Derivatives, 2007). This explains the

    term Asian, which is not related to any geographic positioning.

    Asian options, also referred to as average options, are related to the category

    of exotic options. The payoff of these non-vanilla types of options is path-dependent.

    Other examples are Russian options, Israeli options, chooser options and barrier

    options. In this thesis I am dealing with the Asian option type and since I am going to

    compare this type with European vanilla options I will deal with European-style Asian

    options only.

    Generally, Asian options are broadly segregated into three categories;

    arithmetic average Asians, geometric average Asians and both these forms can be

    averaged on a weighted average basis, whereby a given weight is applied to each

    stock being averaged. This can be useful for attaining an average on a sample with a

    highly skewed sample population (Global Derivatives, 2007). A further breakdown of

    these options implies that they can either be based on the average price of the

    underlying asset, or on the average strike price. In other words, the average price can

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    replace either the stock price at expiration, or the strike price at expiration. In sum,

    four main types of European-style Asian options with accompanying payoff diagrams

    exist:

    Average price call ),0( XSMAX avg =

    Average price put ),0(avg

    SXMAX =

    Average strike call ),0( avgT SSMAX =

    Average strike put ),0( Tavg SSMAX =

    Now assume a three-period case for all types of European-style Asian options

    mentioned above. There are eight possibility outcomes; the average price of the

    underlying asset can go up three times but also down three times. All the possibilities

    are stated in the second column of the table below. The probability of each outcome

    can be found in the third column. In column four the current price at maturity is given,

    taken into account an increase (up) in S(t) of 25% and a decrease (d) in S(t) of 20%.

    Column four gives the average price of the asset over all three periods. The last four

    columns represent the payoffs in each outcome for the discussed types of European-

    style Asian options.

    From the bottom line in the table above one can find the values for each type of Asian

    option. This value is calculated as the sum of the product of the payoffs and the

    respective probability of that payoff, discounted at the risk-free rate of 5% (Chance,

    2004).

    This way of pricing Asian options makes use of the binomial model. For

    European vanilla options this binomial model requires a large number of time steps to

    give an accurate approximation to the price for standard European vanilla options,priced with the Black-Scholes model. Unfortunately there is no similar pricing

    Outcome Path Probability S(T) S(avg) Avg price call Avg price put Avg strike call Avg strike put

    1 uuu 0,171 97,66 72,07 22,07 0,00 25,59 0,00

    2 uud 0,137 62,50 63,28 13,28 0,00 0,00 0,78

    3 udu 0,137 62,50 56,25 6,25 0,00 6,25 0,00

    4 duu 0,137 62,50 50,63 0,63 0,00 11,87 0,00

    5 udd 0,110 40,00 50,63 0,63 0,00 0,00 10,63

    6 dud 0,110 40,00 45,00 0,00 5,00 0,00 5,00

    7 ddu 0,110 40,00 40,50 0,00 9,50 0,00 0,50

    8 ddd 0,088 25,60 36,90 0,00 13,10 0,00 11,30

    Option value = 5,71 2,37 5,92 2,48

    Payoff

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    formula for Asian options that are arithmetic. There exists a formula for Asian options

    that have a geometric average, but these types are rarely traded in the market or

    embedded in financial contracts.

    Furthermore, this binomial model can be used in an illustrative way, but is

    impractical in realistic scenarios. In the example describe above, I dealt with a

    hypothetical three-period case. If for example the average of an Asian option is being

    hold for n periods, the binomial model needs to calculate 2 paths either up or down.

    For a 60-period case this would lead to 1,152,921,504,606,850,000 paths.

    Some formulas to price Asian options exist and are used in practice, but lead

    only to an approximated price. I will go over some of these approximation formulas

    later in my thesis. For further reading on pricing European-style Asian options based

    on the binomial model, see Don M. Chance, An Introduction to Derivatives & Risk

    Management, 6th edition, 2004, chapter 14.

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    3. Pricing methods

    3.1 The Black-Scholes Option Pricing Model

    As the binomial tree model is a basic method for conceptualizing theapproximation of valuating calls and puts, it is not straightforward for practical use.

    The commonly used model for accurately pricing European vanilla stock options is

    the Black-Scholes model. Based on the Capital Asset Pricing Theory and stochastic

    calculus an accurate pricing formula was developed (Black and Scholes, 1973). The

    core concepts of this model are the use of natural logarithm and the exponential

    function. Furthermore, the model is based on a specific set of assumptions. First,

    stock prices behave randomly and evolve according to a lognormal distribution with

    the natural logarithm, e, of the return on the stock. Second, the risk-free rate and

    volatility of the log return on the stock are constant throughout the options life, to

    simplify the model. Next, the model assumes no dividend payments, taxation or

    transaction costs and more strongly, it ignores the possibility of early exercise, such

    that it automatically deals with European options. The end formula for pricing a

    European call is obtained through complex mathematics, but the result is as follows:

    )(*)(* 210 dNXedNSCTr

    ec= ,

    where

    T

    TrXSd c

    )2()ln( 201

    ++= ,

    and

    Tdd=

    12 .

    From this pricing method derives that the price of a European call equals the expected

    value of the stock price at expiration, given the fact that the stock price exceeds the

    exercise price at expiration ( XST > ), discounted at the continuously compounded

    interest rate, Trce . The second part is the expected payout of the entire exercise price

    at expiration. Since this is a future value, it should be multiplied by Trce , but the

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    present value of the call price is needed, so it can be cancelled out. So both )( 1dN

    and )( 2dN are the cumulative normal probabilities of these expressions of the model.

    Inserting the put-call parity into the pricing formula for European calls as

    explained above provides the pricing formula in the Black-Scholes model for

    European put options:

    Tr

    eecXeSCP

    += 0 (put-call parity),

    rewriting into the Black-Scholes model gives

    )](1[)](1[ 102 dNSdNXePTr

    ec =

    This is the commonly used formula for pricing European puts on stock options under

    the aforementioned assumptions. Klemkosky and Resnick (1979) derive from their

    study that inefficiency in their empirical model results to test put-call parity

    consistency is a result of option overpricing or underpricing. This influences the

    accuracy of the Black-Scholes model. For further reading upon the Black-Scholes

    model and put-call parity, see Stoll (1969), MacBeth and Merville (1979), and Chriss

    (1997).

    3.2 The Monte Carlo Simulation Approach

    A fast and very accurate model for pricing path-dependent options such as

    Asian options has yet not been found. Still several researchers have devised

    approximation algorithm for Asian options. Chalsani, Jha and Varikooty (1997)

    conclude that pricing path-dependent options in the binomial tree model of Cox, Ross

    and Rubinstein (1979) is notoriously hard and that the Black-Scholes differential

    equation for the price of such options has no known closed form solution.

    Furthermore they summarize the researches on the approximation algorithm into tree

    categories.

    Geman and Yor (1993) considered an approach by deriving formulas for the

    Laplace transform of an Asian option. The second method, as being investigated by

    Levy and Turnbull (1992), Levy (1992) and Turnbull and Wakeman (1991), consists

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    of approximations on the distribution of arithmetic average on which the payoff of an

    Asian option is based. The pricing method most often used in practice has been

    studied by Kemna and Vorst (1990) and Carverhill and Clewlow (1990). The latter

    have explored Fourier transform techniques, while the first have used Monte Carlo

    simulation to price options based on average value assets.

    By presenting a dynamic hedging strategy from which the value of an average

    option can be derived, Kemna and Vorst (1990) explain mathematically why no

    explicit formula for an average option like the European-style Asian option can be

    derived. According to them the combined process ),( tt AS , that is the price of the

    underlying asset S at time t and the average value A at time t, is not Gaussian in

    character which means it is not a function in the form of

    22 )2/()(

    )(cbx

    aexf

    = . For

    mathematical proof of this, see Kemna and Vorst (1990).

    Therefore they are obliged to use numerical computations, for which they take

    a Monte Carlo simulation approach in finding a valuation model for Asian options.

    This simulation approach generates random numbers according to probabilities that

    are associated with uncertainty (Chance, 2004). This method does not take into

    account American-style Asian options since these are exposed to price manipulation

    as they can be exercised early. Therefore only European-style Asian options are takeninto account.

    The generated numbers from the simulation represent possible changes in

    stock price S , making up the average of the European-style Asian option at a certain

    time interval from a certain point in the future until the maturity date. Mathematically

    this is written out as t . Also, the numbers are based on the continuously

    compounded interest rate Trce and how sensitive the stock price is for changes, i.e. the

    volatility of the stock

    . The variable

    is a random number generated from astandard normal probability distribution. This leads to the general formula:

    tStSrS c +=

    As Kemna and Vorst use their theoretical numerical approximation of the value of an

    average option in line with the Monte Carlo simulation method, they use the normal

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    distribution of

    1

    logi

    i

    St

    St, with mean

    n

    TTr ))(2

    1( 0

    2

    and variancen

    TT )( 02

    in

    the formula to generate a random sequence of future stock prices at nT . For

    mathematical proof of this, see Kemna and Vorst (1990). Independent drawings,

    nxx ,...,1 from the standard normal distribution are generated to simulate this random

    sequence:

    i

    TiTi

    nx

    TT

    n

    TTr

    SS)(

    ))(2

    1(

    loglog 00

    2

    )1()(

    +

    +=

    For each series the change in stock price in the final time interval is calculated and

    then inserted into the formula for the price of an Asian option at maturity. This leads

    for each series to an expectation of the price of on Asian option. Discounting the

    average of all generated expected option price to obtain the present value of the option

    is done using the continuously compounded interest rate, )( 0TTrce . So the expectation

    of the price of an Asian option, ~C, is:

    ( )=

    n

    i

    TTr

    Tc

    ieY

    1

    )( 0* ,

    where

    }0,max XSYavgT

    = .

    More complex options require changes in the Monte Carlo simulation

    procedure, but with European-style Asian options the speed and simplicity of this

    procedure is desirable. Kemna and Vorst (1990) and Grant, Vora and Weeks (1997)

    for example have researched on modifications of the procedure, but in this thesis I

    keep the European-style Asian option pricing method very simplified. Researches,

    however, have shown that with the efficient pricing method using modified and

    extended versions of the Monte Carlo simulation procedure result in sufficient

    analytical approximations on the price of European-style Asian options. For further

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    reading hereupon, see Chalsani, Jha and Varikooty (1997), Vanmaele, Deelstra,

    Liinev, Dhaene and Goovaerts (2006), and Reynaerts, Vanmaele, Dhaene, and

    Deelstra (2006).

    The difference in complexity of pricing European-style Asian options

    compared to European vanilla options is substantial. For the pricing of the vanilla

    options a well-defined pricing formula is available and can be considered as exact.

    This enhanced the ability to sweeping standardization of the European puts and calls.

    Next to the use in OTC markets these types of options are therefore also traded on

    exchange-list basis. In the literature the use of these options are extensively described.

    Institutional investors play this options market by continuously profiting from

    arbitrage opportunities due to the over- and underpricing of vanilla options. Also

    these financial instruments are being used for several hedging strategies. For basic

    ideas, see Hull (2006).

    For the European-style Asian options, however, no ultimate exact pricing

    method has been found, leaving the method described above only to be an accurate

    analytical approximation. This brings along pricing errors, making the application of

    this type of options more complex. Still, the Asian option is preferable in useful in

    practice. I discuss the application in the next section.

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    4. The application of European-style Asian options

    4.1 Stand-alone trades

    In practice a rough distinction can be made between ways of trading withEuropean-style Asian options. On the one hand they are traded as stand-alone

    products in the over-the-counter market, as European-style Asian options are not

    exchange list-based standardized options. The basic findings upon the pricing

    methods used to value European-style Asian options can be a factor that withholds the

    financial markets to trade this type of options based on exchange-list. Milevsky and

    Posner (1998) indicate that the entire volume of Asian options is traded on OTC and

    lies somewhere between five to ten billion US dollars.

    This financial instrument as a stand-alone can be supportive and useful for

    both companies and individual investors or fund managers. For one reason, fund

    managers that hold a portfolio of stocks can face losses from price movements of one

    of these stocks. The fund manager therefore needs to rehedge this price fluctuation

    continuously in order to meet the minimum rate of return. By making use of a

    European-style Asian option on the underlying stock, one does not need to do so, as

    the option is based on the average stock price over the holding period. Hence, the

    fund manager does not need to rehedge the portfolio continuously. Here, the Asian

    option is being used as a hedging instrument.

    Secondly, applying European-style Asian options might be useful for

    companies that need to buy commodities like crude oil, aluminum or gold at a specific

    time of the year. If such companies sell their product regularly throughout the year,

    they are likely to face profit margins as the price of the commodities is volatile.

    Taking a position in Asian options on the underlying commodity allows managers to

    smoothen their profit margin on sales. This is a cost efficient way of hedging cash

    flows over extended periods. Also, in thinly traded asset markets the use of European-

    style Asian options is preferable as in these markets price manipulation near maturity

    is possible (Vanmaele et al., 2006) and furthermore for underlying assets of Asian

    options exchange rates and interest rates are often used (Reynaerts et al., 2006). So

    the Asian option functions as a hedging instrument here.

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    4.2 Embedment in financial contracts

    The characteristics of Asian options make them also useful in complex

    financial contracts and strategies. Nielsen and Sandmann (2003) explain that Asian

    options can also be part of retirement plans, life insurance or corporate financing, by

    giving an example. They consider an investment plan where periodic payments are

    spread over a certain period invested in a specified risky asset. At maturity the value

    of this periodic investment is composed of the price of the asset and the price on each

    of the investment days. In order to guarantee a minimum rate of return on this

    investment plan an Asian option on the average return can be used as a risk reduction

    instrument. This is especially of relevance when the periodic payments are part of a

    retirement scheme.

    Also, Schrager and Pelsser (2004) underline the use of Asian options by

    elaborating on the existing literature on insurance contracts. They extend the way of

    viewing a single premium Unit Linked contract as a stock along with a put option on

    that stock, by explaining that in practice payments of multiple premiums are

    straightforward. It is shown that for a generic structure of the cost and mortality

    deductions the structure of the payoff remains Asian like (Schrager and Pelsser, 2004).

    They also prove the analogy of the guarantee with Asian options by finding equality

    between both the insurance contract and its equivalent.

    A third example of the embedment of Asian options is an Oranje-Nassau bond

    contract. This type of contract consists of a Dutch government bond in combination

    with an option on the average asset value of a commodity. The settlement price of

    such a contract was defined as the average Brent Blend oil price over the last year of

    the contract. The redeemer of the contract was to receive the face value of the bond

    plus the difference between this face value and the settlement price, but had to forfeit

    a percentage of the coupon rate. Similar structures are briefly described by Kemna

    and Vorst (1990) and include examples of Mexican Petrobonds, Delaware Gold

    indexed bonds, Petrolewis oil indexed notes and BT Gold Notes Limited notes. In

    case where the settlement price is lower than the face value, the average option leads

    to the profit of an arbitrage opportunity.

    Finally, Asian options included in bond contracts protect the issuer of any

    possible price manipulation of the underlying asset at maturity. Next to that it gives

    the bond holder also the ability to gain profit from a firm of which its profits mainly

    depends on the price of an underlying asset. For example, if an asset has a low price

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    during the entire holding period of an option, but increase tremendously near maturity,

    then the firm would not be able to pay out the option premiums to the holders in case

    the option would be a European vanilla call option. The use here of a European-style

    Asian option would be preferable in order to smoothen premiums to be paid out by

    this firm and hedges the firms cash flows.

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    5. Conclusion and recommendation

    5.1 Conclusion

    The aim of this thesis is to provide clear answers to the research question:How can valuation and pricing differences between European vanilla options and

    European-style Asian options play a role in applying these options in line with

    determined trading objectives? From my discussion on the application of European-

    style Asian options and the simplified outline on differences in pricing methods

    between these options I have drawn my conclusions.

    The available literature on the various approaches for pricing European-style

    Asian options was too comprehensive to discuss entirely. Since the emphasis of my

    thesis is not on how to price the mentioned options I simplified this to a basic concept.

    I summarized an overview on findings that no accurate exact formula for pricing an

    Asian option is available and that the complexity substantiates its use in practice from

    the standardized European vanilla option. Next to that I mentioned the use of

    European vanilla options briefly and discussed the use of European-style Asian

    options. For each application I indicated for what purposes it was being used.

    In line with the research question stated above I wanted to investigate how the

    complexity of pricing Asian options could make a difference in applying the options

    in line with determined trading objectives. For European vanilla options it is obvious

    to conclude that these derivatives are used to profit from arbitrage opportunities in

    case they are mispriced. Aggressive derivatives traders are constantly looking for such

    opportunities in the market. For European-style Asian options these relative simple

    arbitrage opportunities are not readily available due to the complexity of pricing them.

    So European-style Asian options are not used to gain from arbitrage opportunities in

    stand-alone traded options. In case these options are embedded in financial contracts

    like Oranje Nassau bond contracts, however, they do lead to arbitraging.

    Furthermore, European options are commonly used in hedging strategies and

    extensive literature hereupon is available. The differences in pricing method does not

    influence the possibility to use Asian options in hedging strategies as from the

    discussion on the application can be found that these type of options is commonly

    used to hedge positions as well. The examples I used provide evidence that in certain

    situations institutional and individual investors prefer the complex structure of Asian

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    like payoff diagrams, for example a guarantee of a minimum rate of return on a

    investment plan, equality with multiple premium Unit Linked insurance contracts,

    protection against price manipulation near or at maturity and price smoothening of

    underlying assets in order to hedge cash flows. I conclude that in these cases the

    pricing differences between European vanilla options and European-style Asian

    options play a significant role in setting preferences for the application of these

    options to achieve determined trading objectives as the structure of European-style

    Asian options is preferred.

    5.2 Recommendation

    In this literature study I have investigated the differences in pricing methods

    between European-style Asian options and European plain vanilla options.

    Subsequently I looked for practical examples on the application of Asian options and

    how in practice is determined when European-style Asian options are preferred rather

    than vanilla options considering the pricing differences.

    Further research on the application of Asian options could show how in

    practice is dealt with the complexity of pricing. This could be extended to various

    path-dependent options, as they exist in several variants.

    5.3 Acknowledgement

    I would like to thank my supervisor Jiajia Cui for her comments and

    suggestions.

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