minimax regret and strategic uncertainty this paper introduces a new solution concept a minimax regret equilibrium which allows for the possibility that players are uncertain about the rationality and conjectures of their opponents we provide several applications of our concept in particular we consider pricesetting environments and show that optimal pricing policy follows a non degenerate distribution the induced price dispersion is consistent with experimental and empirical observations baye and morgan 2004

estimating the marginal law of a time series with applications to heavy tailed distributions this article addresses estimating parametric marginal densities of stationary time series in the absence of precise information on the dynamics of the underlying process we propose using an estimator obtained by maximization of the quasi marginal likelihood which is a likelihood written as if the observations were independent we study the effect of the neglected dynamics on the asymptotic behavior of this estimator the consistency and asymptotic normality of the estimator are established under mild assumptions on the dependence structure applications of the asymptotic results to the estimation of stable generalized extreme value and generalized pareto distributions are proposed the theoretical results are illustrated on financial index returns supplementary materials for this article are available online

implementation in minimax regret equilibrium this note studies the problem of implementing social choice correspondences in environments where individuals have doubts about the rationality of their opponents we postulate the concept of minimax regret as our solution concept and show that social choice correspondences that are maskin monotonic and satisfy the no veto power condition are implementable in minimax regret equilibrium for all 0 1

a simplified jump process for common stock returns the specification of a statistical distribution which accurately models the behavior of stock returns continues to be a salient issue in financial economics with the introduction of arithmetic and geometric brownian motion models much attention has recently focused on a poisson mixture of distributions as an appropriate specification of stock returns for example see 12 3 8 10 5 and 1 consistent with empirical evidence these models yield leptokurtic security return distributions and furthermore the specification has much economic intuition in particular one may always decompose the total change in stock price into normal and abnormal components the normal change may be due to variation in capitalization rates a temporary imbalance between supply and demand or the receipt of any other information which causes marginal price changes this component is modelled as a lognormal diffusion process the abnormal change is due to the receipt of any information which causes a more than marginal change in the price of the stock and is usually modeled as a poisson process

option pricing for a jump diffusion model with general discrete jump size distributions we obtain a closed form solution for pricing european options under a general jump diffusion model that can incorporate arbitrary discrete jump size distributions including nonparametric distributions such as an empirical distribution the flexibility in the jump size distribution allows the model to better capture leptokurtic features found in real world data the model uses a discrete time framework and leads to a pricing formula that is provably convergent to the continuous time price as the discretization is increased the solution is easy to implement with fast convergence properties numerical results illustrate the efficiency and accuracy of the proposed model and highlight its robustness and flexibility this paper was accepted by noah gans stochastic models and simulation

the capital structure and investment decisions of the small owner managed firm some exploratory issues in the burgeoning literature on small firm financing the problem of underidentification in respect to the supply of and demand for capital has not been fully resolved in an attempt to progress this issue the current paper looks at some of the issues influencing the demand for finance in small firms which are owner managed the paper is primarily exploratory in nature and argues that a greater emphasis might usefully be placed on the cost of capital dimension in future research into small business financing in particular it is suggested that where the objective of an owner manager is to maintain control of the firm interdependent investment and financing strategies may be chosen to control the small firms cost of capital this in turn indicates that the tendency for some small firms to invest sub optimally and exhibit slower than average growth may not be primarily determined by limitations on their supplies of finance on the demand side it may well be that in addition to equity aversion a suboptimal capital structure decision is made in the form of a reduced demand for debt in other words given the level of equity that an owner manager chooses debt may not be fully expanded to the capacity limit consistent with value maximisation

day of the week effects and asset returns the number of empirical studies using daily stock returns is rapidly increasing researchers generally assume that the distribution of stock returns is identical for all days of the week a convenient statistical assumption but not a necessary condition of market equilibrium nevertheless there are reasons to suspect that the distribution of returns may vary according to the day of the week the most obvious is the impact of weekends on monday s return since monday s return is calculated over three instead of one calender day the mean and variance may well be higher on monday compared with any other daily return perhaps three times as large previous research has examined the daily distribution of stock returns for a monday effect while fama 1965 does not compare daily mean returns he does report that monday s variance is about 20o greater than other daily returns with a traditional distributional assumption regarding the returns on a financial asset specifies that the expected returns are identical for all days of the week contrary to this plausible assumption this paper discovers that the expected returns on common stocks and treasury bills are not constant across days of the week the most notable evidence is for monday s returns where the mean is unusually low or even negative several explanations of the results are investigated but none proves satisfactory aside from documenting significant day of the week effects the implications of the results for tests of market efficiency are examined while market adjusted returns continue to exhibit day of the week effects these effects are no longer concentrated on monday during the last year we have had many conversations with our colleagues throughout the professions we are particularly thankful to the participants at sessions of the western and american finance associations where preliminary versions of this paper were presented special thanks are due to gene fama gailen hite jon ingersoll robert jarrow merton miller clifford smith and rex thompson the expert research assistance of frank rabinovitch and youngsup yun is gratefully acknowledged 1 the list of papers using daily stock returns is too long to name recent examples include charest 1978 dodd 1980 banz 1981 and reinganum 1981

option pricing when the variance changes randomly theory estimation and an application in this paper we examine the pricing of european call options on stocks that have vari ance rates that change randomly we study continuous time diffusion processes for the stock return and the standard deviation parameter and we find that one must use the stock and two options to form a riskless hedge the riskless hedge does not lead to a unique option pricing function because the random standard deviation is not a traded security one must appeal to an equilibrium asset pricing model to derive a unique option pricing function in general the option price depends on the risk premium associated with the random standard deviation we find that the problem can be simplified by assuming that volatility risk can be diversified away and that changes in volatility are uncorrelated with the stock return the resulting solution is an integral ofthe black scholes formula and the distribution function for the variance of the stock price we show that accurate option prices can be computed via monte carlo simulations and we apply the model to a set of actual prices

the variance gamma v g model for share market returns a new stochastic process termed the variance gamma process is proposed as a model for the uncertainty underlying security prices the unit period distribution is normal conditional on a variance that is distributed as a gamma variate its advantages include long tailedness continuous time specification finite moments of all orders elliptical multivariate unit period distributions and good empirical fit the process is pure jump approximable by a compound poisson process with high jump frequency and low jump magnitudes applications to option pricing show differential effects for options on the money compared to in or out of the money copyright 1990 by the university of chicago

oil prices brownian motion or mean reversion a study using a one year ahead density forecast criterion abstract for oil related investment appraisal an accurate description of the evolving uncertainty in the oil price is essential for example when using real option theory to value an investment a density function for the future price of oil is central to the option valuation the literature on oil pricing offers two views the arbitrage pricing theory literature for oil suggests geometric brownian motion and mean reversion models empirically driven literature suggests arma garch models in addition to reflecting the volatility of the market the density function of future prices should also incorporate the uncertainty due to price jumps a common occurrence in the oil market in this study the accuracy of density forecasts for up to a year ahead is the major criterion for a comparison of a range of models of oil price behaviour both those proposed in the literature and following from data analysis the kullbach leibler information criterion is used to measure the accuracy of density forecasts using two crude oil price series brent and west texas intermediate wti representing the us market we demonstrate that accurate density forecasts are achievable for up to nearly two years ahead using a mixture of two gaussians innovation processes with garch and no mean reversion

models of stock returns a comparison in this paper a discrete mixture of normal distributions is proposed to explain the observed significant kurtosis fat tails and significant positive skewness in the distribution of daily rates of returns for a sample of common stocks and indexes stationarity tests on the parameter estimates of this discrete mixture of normal distributions model revealed significant differences in the mean estimates that can explain the observed skewness and significant differences in the variance estimates that can explain the observed kurtosis an alternative explanation for the observed fat tails is the symmetric student model the result of a comparison between the models is that the discrete mixture of normal distributions model has substantially more descriptive validity than the student model for many years both financial economists and statisticians have been concerned with the description of stock market returns the form of the distribution of stock returns is a crucial assumption for mean variance portfolio theory theoretical models of capital asset prices and the prices of contingent claims for example understanding the behavior of the variance is essential to option pricing models empirical tests of asset pricing models and the efficient markets hypothesis draw statistical inferences that are also conditional on distributional assumptions the most convenient assumption for financial theory and empirical methods is that the distribution of security rates of return be multivariate normal with parameters that are stationary over time since the normal distribution is stable under addition any arbitrary portfolio of stocks will also be normally distributed with the additional assumption of risk aversion mean variance theory follows furthermore the assumptions of normality and parameter stationarity are required for most of the econometric techniques typically used in empirical research tests of the normality hypothesis on the daily returns of the dow jones industrial stocks by fama 121 revealed more kurtosis fatter tails than that predicted from a sample of independent and identically distributed normal variates fama concluded from this evidence that the distribution of price changes conforms better to the stable paretian distribution with characteristic exponent

market power assessment and mitigation in hydrothermal systems the objective of this paper is to investigate market power issues in bid based hydrothermal scheduling initially market power is simulated with a single stage nash cournot equilibrium model market power assessment for multiple stages is then carried through a stochastic dynamic programming scheme the decision in each stage and state is the equilibrium of a multi agent game thereafter mitigation measures specially bilateral contracts are investigated case studies with data taken from the brazilian system are presented and discussed

rolling sampled parameters of arch and levy stable models in this paper an asymmetric autoregressive conditional heteroskedasticity arch model and a levy stable distribution are applied to some well known financial indices dax30 ftse20 ftse100 and sp500 using a rolling sample of constant size in order to investigate whether the values of the estimated parameters of the models change over time although there are changes in the estimated parameters reflecting that structural properties and trading behaviour alter over time the arch model adequately forecasts the one day ahead volatility a simulation study is run to investigate whether the time variant attitude holds in the case of a generated arch data process revealing that even in that case the rolling sampled parameters are time varying

measuring price risk in rating revenue coverage bs or no bs the black scholes bs option pricing model has been a cornerstone of modern financial theories since its introduction by black and scholes 1973 and its subsequent refinement by merton 1973 the model has realized widespread adoption for a number of purposes inherent in the model are a number of assumptions an important and potentially restrictive assumption is that the underlying asset price is log normally distributed among the many diverse uses of the bs model the model and underlying theory are used to derive measurements of the variance of expected harvest time prices for use in rating revenue coverage in the federal crop insurance program revenue coverage currently accounts for about 80 of the total liability insured in the program this liability frequently exceeds 100 billion and thus the accuracy of revenue premium rates is of vital importance the use of the bs model by the risk management agency rma of the usda has been the focus of recent criticisms of the program critics have argued in favor of retrospective measures of price variability that are based on historical price movements or have recommended other approaches to measuring price risk this article reports on a contracted review of revenue insurance rating methodology commissioned by rma we evaluate a number of alternative approaches to measuring expected price variability including several approaches recommended by critics of the federal program our results suggest that the bs model is preferred to recommended alternatives on the basis of numerous criteria

mean var portfolio optimization a nonparametric approach portfolio optimization involves the optimal assignment of limited capital to different available financial assets to achieve a reasonable trade off between profit and risk we consider an alternative markowitz s mean variance model in which the variance is replaced with an industry standard risk measure value at risk var in order to better assess market risk exposure associated with financial and commodity asset price fluctuations realistic portfolio optimization in the mean var framework is a challenging problem since optimizing var leads to a non convex np hard problem which is computationally intractable in this work an efficient learning guided hybrid multi objective evolutionary algorithm mode gl is proposed to solve mean var portfolio optimization problems with real world constraints such as cardinality quantity pre assignment round lot and class constraints a learning guided solution generation strategy is incorporated into the multi objective optimization process to promote efficient convergence by guiding the evolutionary search towards promising regions of the search space the proposed algorithm is compared against the non dominated sorting genetic algorithm nsga ii and the strength pareto evolutionary algorithm spea2 experimental results using historical daily financial market data from s p 100 and s p 500 indices are presented experimental results shows that mode gl outperforms two existing techniques for this important class of portfolio investment problems in terms of solution quality and computational time the results highlight that the proposed algorithm is able to solve the complex portfolio optimization without simplifications while obtaining good solutions in reasonable time and has significant potential for use in practice

a new foundation for the mean variance analysis abstract in this paper i re examine how the mean variance analysis is consistent with its traditional theoretical foundations namely stochastic dominance and the expected utility theory then i propose a simplified version of the coarse utility theory as a new foundation i prove that by assuming risk aversion and the normality of asset variables the simplified model is well behaved indifference curves are convex and the opportunity set is concave therefore there exist global optimal portfolios in the market finally i prove that decision making in accordance with the simplified model is consistent with the mean variance analysis

the term structure of credit spreads with jump risk abstract default risk analysis is important for valuing corporate bonds swaps and credit derivatives and plays a critical role in managing the credit risk of bank loan portfolios this paper offers a theory to explain the observed empirical regularities on default probabilities recovery rates and credit spreads it incorporates jump risk into the default process with the jump risk a firm can default instantaneously because of a sudden drop in its value as a result a credit model with the jump risk is able to match the size of credit spreads on corporate bonds and can generate various shapes of yield spread curves and marginal default rate curves including upward sloping downward sloping flat and hump shaped even if the firm is currently in a good financial standing the model also links recovery rates to the firm value at default so that the variation in recovery rates is endogenously generated and the correlation between recovery rates and credit ratings before default reported in altman j finance 44 1989 909 can be justified

conditional heteroscedasticity in time series of stock returns evidence and forecasts this article presents new evidence about the time series behavior of stock prices daily return series exhibit significant levels of second order dependence and they cannot be modeled as linear white noise processes a reasonable return generating process is empirically shown to be a first order autoregressive process with conditionally heteroskedastic innovations in particular generalized autoregressive conditional heteroskedastic garch 1 1 processes fit to data very satisfactorily various out of sample forecasts of monthly return variances are generated and compared statistically forecasts based on the garch model are found to be superior copyright 1989 by the university of chicago

level k mechanism design non equilibrium models of choice e g level k reasoning have significantly different sometimes more accurate predictions in games than does nash equilibrium when it comes to the maximal set of functions that are implementable in mechanism design however they turn out to have similar implications focusing on single valued rules we discuss the role and implications of different behavioural anchors arbitrary level 0 play and prove a level k revelation principle if a function is level k implementable given any level 0 play it must obey a slight weakening of standard strict incentive constraints further the same condition is also sufficient for level k implementability although the role of specific level 0 anchors is more controversial for the sufficiency argument nonetheless our results provide tight characterizations of level k implementable functions under a variety of level 0 play including truthful uniform and atomless anchors

information time option pricing theory and empirical evidence abstract with a stochastic time change from calendar time to information time we derive a parsimonious option pricing formula with stochastic volatility as a risk neutral poisson sum of merton s 1973 prices over the option s information time maturity domain the formula contains two unobservable parameters information arrival intensity and information time asset volatility with stochastic volatility induced by random information arrival when the information arrival rate intensifies the option price increases and vice versa we test the formula in pricing hedging and excess profits capture empirically using currency and the s p 500 futures options transaction data

a data analytic look at skewness and elongation in common stock return distributions this article explores the nature of skewness and elongation in daily common stock return distributions of individual firms using estimates of g for skewness and h for elongation obtained from tukey s g and h distributions both parametric and nonparametric bootstrap estimates of standard errors of the g estimates are computed and compared daily return distributions are first examined cross sectionally over a large sample of firms the estimates of the skewness parameter exhibit variation across individual firms but some general trends are evident across industry groups and firm sizes return distributions typically seem to be more elongated than the gaussian distribution from a time series perspective both skewness and elongation are persistent in the return distributions of individual firms and vary over a finite range first order autocorrelation coefficients of monthly g and h estimates are large and suggest a certain degree of predictability

evaluation of regulatory impacts on dynamic behavior of investments in electricity markets a new hybrid dp game framework a new hybrid framework based on game theory and dynamic programming dp with random demands and prices is proposed for studying the impacts of regulatory interventions on the dynamics of investment in power generation in electricity markets in our approach using markov chains the electric demand and growth of fuel prices have been modeled dp has been used for solving the generation expansion planning gep problem investment strategies of other investors in the market are modeled as constraints the income of the investor is calculated by modeling strategic interactions among market players in the spot energy market the cournot game concept has been applied and the nash equilibrium is calculated for each state and stage of dp simulation results confirm that the proposed framework is an appropriate decision support tool that provides useful information about dynamics of investment

skewness in financial returns abstract in this paper the symmetry of daily returns is addressed in eight international stock markets and three spot exchange rates tests of symmetry with the sample skewness seem of little value due to the non normality of the returns under alternative non normal distributions the symmetry of the returns cannot be rejected for most markets distribution free procedures do not detect strong asymmetries in most of the series either however some differences between returns below the mean and returns over the mean are observed in several markets

nash implementation using undominated strategies we study the problem of implementing social choice correspondences using the concept of undominated nash equilibrium i e nash equilibrium in which no one uses a weakly dominated strategy we show that this mild refinement of nash equilibrium has a dramatic impact on the set of implementable correspondences our main result is that if there are at least three agents in the society then any correspondence which satisfies the usual no veto power condition is implementable unless some agents are completely indifferent over all possible outcomes many common welfare criteria such as the pareto correspondence and several familiar voting rules such as majority and plurality rules satisfy our conditions this possibility result stands in sharp contrast to the more restrictive findings with implementation in either nash equilibrium or subgame perfect equilibrium we present several examples to illustrate the difference between undominated nash implementation and implementation with alternative solution concepts

undominated nash implementation in bounded mechanisms we study implementation in undominated nash equilibrium by bounded mechanisms an undominated nash equilibrium is a nash equilibrium in which no agent uses a weakly dominated strategy a mechanism is bounded if every dominated strategy is dominated by some undominated strategy we identify necessary conditions and sufficient conditions for such implementation these conditions are satisfied in virtually all economic environments and are also satisfied by interesting correspondences from the social choice literature for economic settings we provide a particularly simple implementing mechanism for which the undominated equilibrium outcomes coincide with those obtained from the iterative elimination of weakly dominated strategies

correlations in price changes and volatility across international stock markets the short run interdependence of prices and price volatility across three major international stock markets is studied daily opening and closing prices of major stock indexes for the tokyo london and new york stock markets are examined the analysis utilizes the autoregressive conditionally heteroskedastic arch family of statistical models to explore these pricing relationships evidence of price volatility spillovers from new york to tokyo london to tokyo and new york to london is observed but no price volatility spillover effects in other directions are found for the pre october 1987 period article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

stock price distributions with stochastic volatility an analytic approach we study the stock price distributions that arise when prices follow a diffusion process with a stochastically varying volatility parameter we use analytic techniques to derive an explicit closed form solution for the case where volatility is driven by an arithmetic ornstein ublenbeck or ar1 process we then apply our results to two related problems in the finance literature 1 options pricing in a world of stochastic volatility and 2 the relationship between stochastic volatility and the nature of fat tailes in stock price distributions article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

on measuring skewness and elongation in common stock return distributions the case of the market index this article is an exploratory investigation of the distributional properties of market index returns using j w tukey s g and h distributions specifically it is shown that over sufficiently long periods of time the distribution of the market index is adequately explained as a skewed elongated g x h distribution estimates of skewness and elongation are developed that are easy to calculate and are robust with respect to outliers functional forms for the appropr iate distributions are provided the findings reported here have implications for understanding skewness and elongation developing appropriate portfolio strategies and devising pricing models incorporating higher moments copyright 1988 by the university of chicago

nonnormalities and tests of asset pricing theories the robustness of the multivariate test of gibbons ross and shanken 1986 to nonnormalities in the residual covariance matrix is examined after considering the relative performance of various tests of normality simulation techniques are used to determine the effects of nonnormalities on the multivariate test it is found that where the sample nonnormalities are severe the size and or power of the test can be seriously misstated however it is also shown that these extreme sample values may overestimate the population parameters hence we conclude that the multivariate test is reasonably robust with respect to typical levels of nonnormality in traditional hypothesis testing a nonrandom test maps the values of a random variable into a sample space dichotomized into regions where a hypothesis is either accepted or rejected there are three possible outcomes from this process 1 a correct decision 2 a false rejection type i error or 3 failure to reject the hypothesis when it is false type ii error of the latter two types of error an error of the first kind is usually considered less desirable so typically a level of significance is selected with low probability of type i error e g 0 05 or 0 01 and a test is chosen so as to maximize power minimize probability of type ii error for the specified level of type i error knowledge of the relative level of these two errors is critical in assimilating the results of an experiment for example if the power of a test is equal to its significance level i e a weak test rejection of the null contains zero information 2 additionally in constructing parametric tests of hypotheses it is necessary to assume some distribution for the underlying data consequently when using parametric tests rejection of the null is only equivalent to rejection of at least one of the underlying hypotheses i e the null hypothesis or the distributional assumption interestingly the size significance level and power of procedures used to test

implementation in undominated nash equilibria without integer games a mechanism which uses neither integer games nor modulo games is shown to implement any social choice function in a production economy with private and excludable public goods more precisely th

the ex ante and ex post price effects of quarterly earnings announcements reflected in option and stock prices the subject of this study is the effect of investors anticipations of impending informative disclosures on the behavior of option and stock prices our approach introduced in a previous paper patell and wolfson 1979 and substantially extended here represents the following significant departure from traditional information content studies instead of analyzing security price reactions to announcements we analyze preannouncement option prices in order to discern investors beliefs about the range of possible stock price reactions expected to accompany a forthcoming disclosure whose actual content is not yet known in the tests reported here we focus on quarterly earnings announcements as disclosure events whose timing is predictable and we attempt to detect their systematic influence on the relationship between stock and option prices our operational definition of information content emphasizes changes in the variability of common stock returns in response to earnings disclosures while market efficiency precludes investors from predicting the direction of the stock price change which will accompany a future earnings announcement it is likely that investors will anticipate increased price variability at the time of disclosure and indeed several studies have documented announcement date increases in stock price volatility

extracting market information from equity options with exponential levy processes levy processes have been successfully applied in the modeling of financial assets useful information such as implied volatility skewness and risk preferences can be derived from market option prices in this paper we advocate using esscher conjugate levy processes to estimate risk neutral and empirical densities more specifically we employ the exponential meixner and nig processes to calculate in closed form the pricing kernel in the equity market and then study the evolution of equity market behavior between 2002 and 2010 our empirical analysis using s p 500 options shows that the risk preferences of equity investors were signalling an anomaly in the market well before the subprime prime mortgage crisis august 2007 and the crisis of confidence that followed anticipating the downfall in equity markets in 2008 but then returning to normal levels in 2009

hydrothermal market simulator using game theory assessment of market power the aim of this work is to build a model able to simulate a hydrothermal electric power market based on simple bids to a power exchange the model studies the behavior of different market agents in a short term horizon and delivers information about spot prices use of water and other relevant variables initially a thermoelectric market is simulated through a static model based on cournot concepts the addition of hydroelectric power stations and time dependencies is made later using a dynamic programming algorithm to build a dynamic model in each stage and state of the dynamic programming a nash cournot equilibrium is determined to assess the behavior of the thermoelectric power stations static model different strategies that firms can follow and the consequences of each one of them are analyzed market power mitigation effects of physical and financial bilateral contracts are also investigated a case study with data on the chilean power system is presented and analyzed

minute by minute efficiency normality and randomness in intra daily asset prices in this study we test the efficiency of asset markets at intervals as short as 30 seconds we also describe the properties of a simple new stochastic process as a potential model of the behaviour of asset prices and test it on intra daily deutsche mark futures prices according to this process asset prices are constant between economically relevant events which occur at the random times generated by a poisson process at the moments of these events prices jump to new values the size of the jump is drawn from a normal distribution tests of this process indicate that it cannot be rejected for most of the days in the sample

short sales in log robust portfolio management abstract this paper extends the log robust portfolio management approach to the case with short sales i e the case where the manager can sell shares he does not yet own we model the continuously compounded rates of return which have been established in the literature as the true drivers of uncertainty as uncertain parameters belonging to polyhedral uncertainty sets and maximize the worst case portfolio wealth over that set in a one period setting the degree of the manager s aversion to ambiguity is incorporated through a single intuitive parameter which determines the size of the uncertainty set the presence of short selling requires the development of problem specific techniques because the optimization problem is not convex in the case where assets are independent we show that the robust optimization problem can be solved exactly as a series of linear programming problems as a result the approach remains tractable for large numbers of assets we also provide insights into the structure of the optimal solution in the case of correlated assets we develop and test a heuristic where correlation is maintained only between assets invested in in computational experiments the proposed approach exhibits superior performance to that of the traditional robust approach

rational entry into risky markets with negative expected returns the role of biased misestimation of profit potential abstract we extend the theory of negative long run profits in risky industries by incorporating a negatively skewed profit distribution rational behavior with incomplete information is introduced by allowing economic agents to know the median rather than the mean rate of return we compare this to the case involving postdecision bolstering where entrants choose to discount available information on the industry profit distribution monte carlo experiments are tailored to the experience of the u s home building industry

student t distribution based var mgarch an application of the dcc model on international portfolio risk management significant second moment transmission effects and obvious time varying patterns of correlation coefficients among major equity and currency markets in the us japan and the uk are found to exist such observations inspire the time varying setting of dynamic conditional correlation coefficients in mgarch models on the other hand the multivariate student t distribution is suitable for analysing the visible leptokurtosis that is common in financial markets both are important for international portfolio risk management thus a comparison on the hedging efficiency of hypothetical portfolios consisting of stock and currency future positions is conducted in order to justify the multivariate student t distribution based on the dcc mgarch model

extracting probabilistic information from the prices of interest rate options tests of distributional assumptions return distributions in general and interest rates in particular have been observed to exhibit skewness and kurtosis that cannot be explained by the log normal distribution using g and h distribution we derived a closed form option pricing formula for pricing european options we measured its performance using interest rate cap data and compared it with the option prices based on the lognormal burr 3 weibull and gb2 distributions we observed that the g and h distribution exhibited a high degree of accuracy in pricing options much better than those other distributions in extracting probabilistic information from the option market

bounds and prices of currency cross rate options abstract this paper derives the pricing bounds of a currency cross rate option using the option prices of two related dollar rates via a copula theory and presents the analytical properties of the bounds under the gaussian framework our option pricing bounds are useful because 1 they are general in the sense that they do not rely on the distribution assumptions of the state variables or on the selection of the copula function 2 they are portfolios of the dollar rate options and hence are potential hedging instruments for cross rate options and 3 they can be applied to generate bounds on deltas the empirical tests suggest that there are persistent and stable relationships between the market prices and the estimated bounds of the cross rate options and that our option pricing bounds obtained from the market prices of options on two dollar rates and the historical correlation of two dollar rates are highly informative for explaining the prices of the cross rate options moreover the empirical results are consistent with the predictions of the analytical properties under the gaussian framework and are robust in various aspects

the distribution of stock returns new evidence against the stable model we present a simple but effective procedure for determining whether a reasonably large sample comes from a stable population against the alternative that it comes from a population with finite higher moments the procedure uses the fact that a stable population sample has moments of the fourth and sixth order whose magnitudes increase very rapidly as the sample size increases this procedure shows convincingly that stock returns when taken as a group do not come from stable populations even for individual stocks our results show that the stable population model null hypothesis can be rejected for more than 95 of the stocks

on jump processes in the foreign exchange and stock markets exchange rates exhibit systematic discontinuities even after allowingfor conditional heteroskedasticity in the diffusion process the results are much more significant in theforeign exchange market than in the stock market which suggests differences in the structure of these markets finally this jump component is shown to explain some of the empirically observed mispricings in the currency options market the objective of this article is to analyze and compare the empirical distribution of returns in the stock market and in the foreign exchange market there are a number of reasons why a better understanding of the stochastic processes driving prices in these markets would be useful many financial models rely heavily on the assumption of a particular stochastic process while relatively little attention is paid to the empirical fit of the postulated distribution as a result models like option pricing models are applied indiscriminately to various markets such as the stock market and the foreign exchange market when the underlying processes may be fundamentally different the foreign exchange market for instance is characterized by active exchange rate man

option pricing under a normal mixture distribution derived from the markov tree model abstract we examine a markov tree mt model for option pricing in which the dynamics of the underlying asset are modeled by a non iid process we show that the discrete probability mass function of log returns generated by the tree is closely approximated by a continuous mixture of two normal distributions using this normal mixture distribution and risk neutral pricing we derive a closed form expression for european call option prices we also suggest a regression tree based method for estimating three volatility parameters and required to apply the mt model we apply the mt model to price call options on 89 non dividend paying stocks from the s p 500 index for each stock symbol on a given day we use the same parameters to price options across all strikes and expires comparing against the black scholes model we find that the mt model s prices are closer to market prices

insider trading abnormal return and preferential information supervising through a probabilistic model abstract the enforcement of the ban on insider trading requires an evaluation of the disgorgement i e the capital gain of the insider trader who takes advantage of the exploitation of preferential information an initial step forward on this topic has been taken by the sec the united states securities and exchange commission which has developed a quantitative procedure based on the event study methodology this paper develops an adaptation of this procedure for the italian market and explains the limits of these methodologies in the analysis of the insider trading phenomenon in particular it emerges that the econometric approach cannot be applied to all insider trading schemes in fact in order to work out statistically significant results it relies on a series of assumptions such as the existence of a robust reference market index or the availability of long time series data for this reason a new procedure for computing the economic value of the information exploited by the insider based on a probabilistic approach has also been developed this methodology overcomes the issues connected to the event study procedure and can be applied by construction to all insider trading schemes and not only to the simplest ones in fact the model parameters are defined by using the trading strategy of the single insider thus if insider trading takes place the model is able to offer a disgorgement computation hence by hypotheses of its construction it is able to detect the difference between insiders and followers the new procedure has been adopted by consob and has been presented to the judicial system which is in charge of inflicting the fine

a game theoretic model for generation expansion planning problem formulation and numerical comparisons this paper presents an application of noncooperative game theory to generation expansion planning gep in a competitive electricity industry the authors apply the cournot model of oligopoly behavior to formulate a gep model that may characterize expansion planning in a competitive regime particularly in pool dominated generation supply industries numerical experiments are conducted on a test system to analyze generation investment and market participation decisions of candidate expansion units that vary in costs and forced outage rates the numerical results point to 1 greater industry expansion and system reliability under cournot competition than under centralized expansion planning and 2 higher probabilistic measures of reliability from multi player expansion than from expansion by a traditional monopolist with an equivalent reserve margin requirement furthermore the authors summarize analytical results involving a simplified version of the gep game

the effects of estimation error on measures of portfolio credit risk abstract this paper uses monte carlo simulations to assess the impact of noisy input parameters on the accuracy of estimated portfolio credit risk assumptions about input quality are derived from the distribution of historical sample statistics commonly used in default risk modelling the resulting estimation error in the distribution of portfolio losses is considerable losses that are judged to occur with a probability of 0 3 may actually occur with a probability of 1 the paper also shows that estimation error leads to biases in value at risk estimates and significance levels of backtests the biases can be corrected by analysing predictive distributions which average over the unknown parameter values

evidence on price stabilization and underpricing in early ipo returns using data on 560 firm commitment initial public offerings of common stock for the 1982 1983 period we find that the cross sectional distribution of one day returns is modeled better as a mixture of two distributions with the parameter estimates of one distribution being consistent with underpricing and the other with price stabilization further the evidence that early ipo returns are drawn from a mixture distribution persists for at least four weeks the implications of these results for the analysis of ipo returns are illustrated by examining the influence of a measure of ex ante price uncertainty on ipo pricing

modeling market power by natural gas producers and its impact on the power system strategic behavior by natural gas producers may influence the operation as well as the development of an electricity system within this paper a computational game theoretic investment model is presented which allows assessing market power by natural gas producers and its effects on the electricity market under consideration of emission markets the model is formulated as a mixed complementarity problem it uses typical time segments to represent both seasonal load fluctuations on the natural gas market and load fluctuations within a day on the electricity market investment is possible in natural gas production and lng infrastructure as well as power plants a test case is presented covering three regions and simultaneously optimizing power plant dispatch and utilization of transmission lines on the power market as well as supply transport and storage on the natural gas market we compute prices production volumes and power plant utilization for two different market power specifications to show the impact of oligopolistic market behavior

implementation in undominated strategies a look at bounded mechanisms this paper examines the impact of placing natural restrictions on the mechanisms considered for implementation problems it is shown that if all mechanisms are considered and preferences satisfy a basic condition then any social choice correspondence can be implemented in undominated strategies an example points out that the strength of this result derives from the use of mechanisms with questionable features in part of the message space the agent who announces the highest integer is rewarded this sort of tail chasing construction common in the constructive proofs of the literature is used to assure that undesired strategy combinations do not form an equilibrium if such mechanisms are ruled out then the social choice correspondences which can be implemented in undominated strategies satisfy an incentive compatibility type condition called strategy resistence for social choice functions this is equivalent to strategy proofness this contrast suggests that this issue should be examined as it applies to other solution concepts used in implementation theory the last portion of the paper begins to explore the issue as it relates to nash implementation and undominated nash implementation

regret aversion and opportunity dependence this paper provides an axiomatic model of decision making under uncertainty in which the decision maker is driven by anticipated ex post regrets our model allows both regret aversion and likelihood judgement over states to coexist also we characterize two special cases minimax regret with multiple priors that generalizes savage s minimax regret and a smooth model of regret aversion

an application of the chi squared goodness of fit test to discrete common stock returns this article presents the centered method for establishing cell boundaries in the x 2 goodness of fit test which when applied to common stock returns significantly reduces the high bias of the test statistic associated with the traditional mann wald equiprobable approach a modified null hypothesis is proposed to incorporate explicitly the usually implicit assumption that the observed discrete returns are approximated by the hypothesized continuous density simulation results indicate extremely biased x 2 values resulting from the traditional approach particularly for low priced and low volatile stocks daily stock returns for 114 firms are tested to determine whether they are approximated by a normal or one of several normal mixture densities results indicate a significantly higher degree of fit than that reported elsewhere to date

option values under stochastic volatility theory and empirical estimates abstract this paper numerically solves the call option valuation problem given a fairly general continuous stochastic process for return volatility statistical estimators for volatility process parameters are derived and parameter estimates are calculated for several individual stocks and indices the resulting estimated option values do not differ dramatically from black scholes values in most cases although there is some evidence that for longer maturity index options black scholes overvalues out of the money calls in relation to in the money calls

a general distribution for describing security price returns this paper introduces a generalized distribution called the gb2 distribution for describing security returns the distribution is extremely flexible containing a large number of well known distributions such as the lognormal log t and log cauchy distribu tions as special or limiting cases and allowing large even infinite higher moments this flexibility allows a direct representation of different degrees of fat tails in the distribution the properties of the gb2 make it useful in empirical estimation of security returns and in facilitating the development of option pricing models and other models that depend on the specification and mathematical manipulation of distributions copyright 1987 by the university of chicago

skewness persistence in common stock returns recent empirical studies have found ex post common stock returns to be consistently positively skewed the frequency of positive skewness in this study is found to be relatively stable over varying time periods from 1961 to 1980 however the skewness of individual stocks and portfolios of stocks does not persist across different time periods positively skewed equity portfolios in one period are not likely to be positively skewed in the next time period past positively skewed returns do not predict future positively skewed returns

forecasting next day electricity prices by time series models in the framework of competitive electricity markets power producers and consumers need accurate price forecasting tools price forecasts embody crucial information for producers and consumers when planning bidding strategies in order to maximize their benefits and utilities respectively this paper provides two highly accurate yet efficient price forecasting tools based on time series analysis dynamic regression and transfer function models these techniques are explained and checked against each other results and discussions from real world case studies based on the electricity markets of mainland spain and california are presented

efficient determination of cournot equilibria in electricity markets this paper analyzes the deregulated electricity market using game theory and investigates the properties of cournot equilibrium points a new algorithm for the calculation of the cournot equilibrium of an electricity market in the absence of transmission constraints is presented the algorithm is based on the transformation of the cournot game into a three level decision making scheme with economic signal exchange the algorithm is tested on a hypothetical market in order to demonstrate the effects of market concentration and demand elasticity case studies indicate that the algorithm is very efficient computationally and therefore suitable for use with multi period production scheduling models for the electricity market

entry into the electricity market uncertainty competition and mothballing options the present paper analyzes the entry strategies into the electricity market of two firms that have power plants under price uncertainty and competition we consider the symmetric and asymmetric two firms which have either a thermal power plant or a nuclear power plant the differences between the thermal power plant and the nuclear power plant such as the cost structure and operational flexibility are modeled the threshold values of market entry are calculated for each firm with either the thermal power plant or the nuclear power plant as the leader or the follower we show the dependence of cost structures on entry thresholds of the leader and the follower into the electricity market for various market and cost conditions the diagrams of the leader are also shown

the bootstrap approach for testing skewness persistence this study presents a new methodology for testing changes in skewness between time periods or samples using the bootstrap method a monte carlo simulation experiment was conducted to compare the effectiveness of the bootstrap method with the method suggested by lau wingender and lau 1989 to test skewness persistence the results show the bootstrap method to be more powerful than the other method the bootstrap method was also used to determine the persistence of skewness in stock returns the results show that in a large percentage of stocks skewness persists over time

the time variance relationship of security returns implications for the return generating stochastic process using a test statistic which specifically allows for parameter shifts over time we investigate the time variance relationship of security returns the null hypothesis of stationary and independent increments is rejected and the existence of a complex short term reversal phenomenon is reported

linear complementarity models of nash cournot competition in bilateral and poolco power markets two cournot models of imperfect competition among electricity producers are formulated as mixed linear complementarity problems lcps and a simple example is presented to illustrate their application the two models simulate bilateral markets the models include a congestion pricing scheme for transmission but other transmission pricing approaches can also be represented in this framework the two models differ from each other in that one has no arbitrage between nodes of the network while in the other model arbitragers erase any noncost based differences in price the latter bilateral model turns out to be equivalent to a cournot model of a poolco the models differ from other cournot market models in that they include both of kirchhoff s laws via a dc approximation can include arbitragers possess unique solutions and are readily solved by efficient lcp algorithms the key assumption that permits their formulation as lcps is that each producer naively assumes that its output will not affect transmission prices

irrationality and ambiguity in extensive games abstract based on a model where deviations from equilibrium play are assumed to identify irrational players who are characterized by ambiguous set valued strategies this paper introduces an equilibrium notion for extensive games with ambiguity averse players that yields a precise interpretation for the counterfactual reasoning usually associated with backward induction the resulting equilibria are always nash equilibria but may not satisfy the conditions required for various refinements of nash equilibrium including those for subgame perfection existence of such equilibria is proved for all two player games and for n player games with perfect information

nash equilibrium and welfare optimality if is a set of social alternatives a social choice rule scr assigns a subset of a to each potential profile of individuals preferences over a where the subset is interpreted as the set of welfare optima a game form or mechanism implements the social choice rule if for any potential profile of preferences 1 any welfare optimum can arise as a nash equilibrium of the game form implying in particular that a nash equilibrium exists and 2 all nash equilibria are welfare optimal the main result of this paper establishes that any scr that satisfies two properties monotonicity and no veto power can be implemented by a game form if there are three or more individuals the proof is constructive

an empirical study of applied game theory transmission constrained cournot behavior restructured energy markets present opportunities for the exercise of market power meaning market players can potentially maintain prices in excess of competitive prices in this paper we investigate cournot equilibrium in a simple example network we analyze three market players in a transmission constrained system and consider nonconstant marginal cost several scenarios are evaluated that show a pure strategy equilibrium can break down even when a transmission constraint exceeds the value of the unconstrained cournot equilibrium line flow

bootstrapping financial time series it is well known that time series of returns are characterized by volatility clustering and excess kurtosis therefore when modelling the dynamic behavior of returns inference and prediction methods based on independent and or gaussian observations may be inadequate as bootstrap methods are not in general based on any particular assumption on the distribution of the data they are well suited for the analysis of returns this paper reviews the application of bootstrap procedures for inference and prediction of financial time series in relation to inference bootstrap techniques have been applied to obtain the sample distribution of statistics for testing for example autoregressive dynamics in the conditional mean and variance unit roots in the mean fractional integration in volatility and the predictive ability of technical trading rules on the other hand bootstrap procedures have been used to estimate the distribution of returns which is of interest for example for value at risk var models or for prediction purposes although the application of bootstrap techniques to the empirical analysis of financial time series is very broad there are few analytical results on the statistical properties of these techniques when applied to heteroscedastic time series furthermore there are quite a few papers where the bootstrap procedures used are not adequate