sharing and anti sharing in teams compared to budget balanced sharing contracts anti sharing may improve the eciency of teams the anti sharer collects a fixed payment from all team members he receives the actual output and pays out its value to them if a team members becomes anti sharer he will be unproductive in equilibrium hence internal anti sharing fails to yield the first best outcome anti sharing is more likely to yield a higher team profit than sharing the larger the team the curvature of the production function or the marginal eort cost sharing is more likely to be better the greater the marginal product the cross partials of the production function or the curvature of the eort cost

the democratic political economy of progressive income taxation why do both left and right political parties typically propose progressive income taxation schemes in political competition analysis of this problem has been hindered by the two dimensionality of the issue space to give parties a choice over a domain that contains both progressive and regressive income tax policies requires an issue space that is at least two dimensional nash equilibrium in pure strategies of the standard two party game whose players have complete preferences over a two dimensional policy space generically fails to exist i introduce a new equilibrium concept for political games based on the fact of factional conflict within parties each party is supposed to consist of reformists militants and opportunists each faction has a complete preference order on policy space but together they can only agree on a partial order nash equilibria of the two party game where the policy space consists of all quadratic income tax functions and each party is represented by its partial order exist and it is shown that in such equilibria both parties propose progressive income taxation

the impact of firm specific news on implied volatilities we study the implied volatility behavior of call options around scheduled news announcement days implied volatilities increase significantly during the pre event period and reach a maximum on the eve of the news announcement after the news release implied volatility drops sharply and gradually moves back to its long run level only on the event date are movements in the price of the underlying significantly larger than expected these results confirm the theoretical results of merton 1973

are price limits really bad for equity markets despite widely documented criticisms price limit rules are present in many equity markets around the world using a game theoretic model we argue that if the cost of monitoring a market is high price limit rules are beneficial empirical tests based on a cross section of 43 equity markets across five continents support our theoretical prediction we find that the probability of the existence of price limit rules is greater in markets that incur higher monitoring costs due to poorer business disclosure more corruption and less efficiency in legal regulatory and technological environments

moral hazard in risk averse teams holmstrom 1982 has shown that a non budget balancing contract induces a team of risk neutral agents to choose the first best effort levels this is not generally true when agents are risk averse furthermore a massacre contract which punishes all but one agent when the outcome is low can attain the first best over a wider range of parameters than any other budget balancing contract

the pricing of options on assets with stochastic volatilities one option pricing problem that has hitherto been unsolved is the pricing of a european call on an asset that has a stochastic volatility this paper examines this problem the option price is determined in series form for the case in which the stochastic volatility is independent of the stock price numerical solutions are also produced for the case in which the volatility is correlated with the stock price it is found that the black scholes price frequently overprices options and that the degree of overpricing increases with the time to maturity one option pricing problem that has hitherto remained unsolved is the pricing of a european call on a stock that has a stochastic volatility from the work of merton 12 garman 6 and cox ingersoll and ross 3 the differential equation that the option must satisfy is known the solution of this differential equation is independent of risk preferences if a the volatility is a traded asset or b the volatility is uncorrelated with aggregate consumption if either of these conditions holds the risk neutral valuation arguments of cox and ross 4 can be used in a straightfoward way this paper produces a solution in series form for the situation in which the stock price is instantaneously uncorrelated with the volatility we do not assume that the volatility is a traded asset also a constant correlation between the instantaneous rate of change of the volatility and the rate of change of aggregate consumption can be accommodated the option price is lower than the blackscholes b s 1 price when the option is close to being at the money and higher when it is deep in or deep out of the money the exercise prices for which overpricing by b s takes place are within about ten percent of the security price this is the range of exercise prices over which most option trading takes place so we may in general expect the b s price to overprice options this effect is exaggerated as the time to maturity increases one of the most surprising implications of this is that if the b s equation is used to determine the implied volatility of a near the money option the longer the time to maturity the lower the implied volatility numerical solutions for the case in which the volatility is correlated with the stock price are also examined the stochastic volatility problem has been examined by merton 13 geske 7 johnson 10 johnson and shanno 11 eisenberg 5 wiggins 16 and

do regulations work a comprehensive analysis of price limits and trading restrictions in experimental asset markets with deterministic and stochastic fundamental values abstract we examine how traders react to two prominent stock market regulations under a constant fundamental value fv process price limits and trading restrictions significantly reduce the price level and mispricing size when traders are inexperienced under a markov process fv there is no evidence for these regulations to reduce mispricing the novel markov process also serves as a testbed for several financial hypotheses related to the regulations we find that price limits do not improve reactions to market news and the binding of price limits magnifies the momentum in the price movements these findings suggest that the scope of these regulations is limited and that they can backfire in some market environments

a contribution to event study methodology with an application to the dutch stock market abstract this paper proposes an extended market model for event studies based on daily stock returns for actual data the assumptions of the simple market model are violated the return distribution is not normal and neither the variance of the error term nor the risk parameter beta are constant our model incorporates the generalized autoregressive conditional heteroskedasticity garch model with t distributed errors and a time dependent beta we test for anomalies by adding dummy variables in the regression equation our model is fairly general and could be used in a wide variety of event study situations we illustrate the model by an analysis of the weekend and the option expiration effect we use return data from the dutch stock market the weekend effect on stock returns is significant but no expiration effect could be detected

widening price limit effects evidence from an emerging stock market abstractthis study investigates the impact of the widening of price limits on the taiwan stock exchange from 7 to 10 by comparing the differences in performance with the different price limit l

the term structure of implied forward volatility recovery and informational content in the corn options market using a flexible method we develop the term structure of volatility implied by corn futures options with differing maturities and evaluate its ability to predict subsequent realized price volatility the implied forward volatilities anticipate realized volatility well for the nearby interval the implied forward volatilities provide unbiased forecasts and are superior to forecasts based on historical volatilities for more distant intervals early year options predict the direction and magnitude of future volatility changes about as well as a three year moving average and better than a naive forecast however later year options display less forecast power in part due to reduced trading activity

price limits and stock market volatility abstract we examine the relationship between price limits and stock market volatility we find when price limits are made more less restrictive stock market volatility is usually not lower higher this finding contradicts conventional wisdom and the view of most regulators

volume volatility and new york stock exchange trading halts trading halts increase rather than reduce both volume and volatility volume volatility in the first full trading day after a trading halt is 230 percent 50 to 115 percent higher than following pseudohalts nonhalt control periods matched on time of day duration and absolute net of market returns these results are robust over different halt types and news categories higher posthalt volume is observed into the third day while higher posthalt volatility decays within hours the extent of media coverage is a partial determinant of volume and volatility following both halts and pseudohalts but a separate halt effect remains after controlling for the media effect in the wake of the 1987 market break a number of commentators including the presidential task force on market mechanisms recommended the establishment of circuit breaker mechanisms the primary argument supporting circuit breakers both price limits and trading halts is that nontrading periods provide an opportunity for normal information transmission in times of market duress proponents of circuit breakers claim that during major price changes there can be a breakdown in the transmission of information between the trading floor and market participants therefore the primary function of a circuit breaker should be to reinform participants greenwald and stein 1988 p 17 by lowering informational asymmetries between traders halts could permit the orderly emergence of a new consensus price but would informative trading halts succeed many academics are openly suspicious of any kind of market interference and assume that trading halts are guilty until proven innocent grossman 1990 p 3 for example argues that the closing of markets merely prevents consenting adults from carrying out their desires on the floor of the stock exchange not only do halts impose a liquidity cost on traders but studies suggest that information will not be as

jump diffusion option valuation in discrete time we develop a simple discrete time model to value options when the underlying process follows a jump diffusion process multivariate jumps are superimposed on the binomial model of cox ross and rubinstein 1979 to obtain a model with a limiting jump diffusion process this model incorporates the early exercise feature of american options as well as arbitrary jump distributions it yields an efficient computational procedure that can be implemented in practice as an application of the model we illustrate some characteristics of the early exercise boundary of american options with certain types of jump distributions jump diffusion processes are popular in option valuation models these processes were incorporated by merton 1976 into the theory of option valuation and constitute an important alternative to the lognormal diffusion process assumed in the black and scholes 1973 model in this paper we develop a tractable discrete time model for valuing options with these processes many authors have suggested that incorporating jumps in option valuation models may explain some of the large empirical biases exhibited by the black scholes model 1 however in many cases closed form solutions for valuing options are not available for example this is true when there is a positive probability of early exercise when the jump distribution is neither lognormal nor discrete or when the option is based on the term structure of interest rates see ahn and thompson 1988 and jarrow and madan 1991 in these important cases the model developed in this paper can be used to value options another aim of this paper is to provide a model which relies on only simple mathematics to price options with jump diffusion processes it is hoped that the key economic relationships underlying jump diffusion models are transparent in this model we provide enough details to make the procedure readily accessible

the switch from continuous to call auction trading in response to a large intraday price movement some european exchanges e g euronext frankfurt and madrid make use of a mechanism to moderate price volatility that was proposed by madhavan 1992 as preferable to a trading halt in times of market stress it consists of a temporary switch from continuous to call auction trading in an individual security whenever its price moves beyond predetermined limits this article studies whether this mechanism sharpens the information content of prices dampens volatility and normalizes trading volume and intensity taking intraday data for the madrid order driven continuous market i find post switch improvements in the information content of prices and reductions in volatility especially for thinly traded stocks trading volume and intensity peaked around auctions but soon returned to preevent levels

a welfare comparison of private and public monopoly abstract the cost function of a monopoly is c q k q where is unknown to the regulator we evaluate various ownership and regulation regimes in terms of social welfare determined by both the amount of total surplus and its distribution maximal welfare is achieved by the regulated public firm when its bias is pro consumer and also when it is pro worker and is low enough we compare an unregulated public firm with a private one regulated a la loeb magat baron myerson and characterize the frontier in parameter space where one or the other dominates

a model of a team contest with an application to incentives under list proportional representation abstract we develop a model of a team contest for multiple indivisible prizes team members exert costly effort to improve their team s success we analyze two intrateam allocation rules under a list rule prizes are allocated according to a predetermined list under an egalitarian rule prizes are allocated according to a fair lottery we show that which allocation rule maximizes team success depends on the degree of complementarity between members efforts and the convexity of the individual cost of effort function we then apply the model to the context of elections under proportional representation with both open and closed lists we derive conditions under which closed lists generate stronger incentives than open lists our results offer a rationale for the lack of evidence on the negative incentive effects of closed lists

political manipulation of a public firm s objective function abstract in the context of a government owned public firm that competes with a private firm this paper demonstrates how the government can maximize its true objective by assigning the public firm a different objective function interestingly this assigned objective function need bear no resemblance to the actual objective being sought enabling the government to disguise a politically unpopular agenda and or outside influence

transitory price changes and price limit rules evidence from the tokyo stock exchange we compare the volatility of 24 hour returns computed from the opening and closing prices of a diverse sample of tokyo stock exchange tse stocks we find that volatility at the open is greater than volatility at the close only for the most actively traded tse stocks daytime and overnight return covariances suggest that the volatility patterns are explained by the effect of implicit bid ask spreads at the open and partial price adjustment at the close both of which are related to the intensity of trading our results challenge the view that open to open returns are more volatile than close to close returns for stocks in general and are consistent with the hypothesis that tse price limit rules have a significant impact on the dynamics of security prices

stock return cross autocorrelations and market conditions in japan we show that changes in market conditions significantly affect cross autocorrelations and speed of adjustment in weekly stock returns we find significant positive cross autocorrelations between weekly returns on a portfolio of small firms and lagged large firm portfolio returns only when the lagged aggregate market has experienced a decline in value these positive return cross autocorrelations are also associated with lower abnormal portfolio trading volume and greater delays in the adjustment of individual stock prices to negative market wide information particularly for small firms the effect of lagged market states cannot be explained by market microstructure biases such as nonsynchronous trading or thin trading

asymmetric treatment of identical agents in teams abstract we investigate when identical agents will be treated asymmetrically in a simple team setting asymmetric treatment is optimal when the agents individual contributions to team performance are strategic complements symmetric treatment of identical agents is optimal when the agents contributions are strategic substitutes or when they are independent

a conditional distribution model for limited stock index returns abstract when a price limit regime exists for all of the stocks involved in an index the index return is an aggregate of limited variables and thereby it is restricted to the same limits we argue that neither a censored nor a truncated distribution model is appropriate for the aggregate return the proposed mixed beta distribution allows for varying conditional mean and volatility and with increasing volatility it changes from leptokurtic to platykurtic densities the model is illustrated and statistically evaluated with an empirical application to the shanghai stock market index returns under a 10 price change limit regime

how markets process information news releases and volatility we examine the impact of scheduled macroeconomic news announcements on interest rate and foreign exchange futures markets we find these announcements are responsible for most of the observed time of day and day of the week volatility patterns in these markets while the bulk of the price adjustment to a major announcement occurs within the first minute volatility remains substantially higher than normal for roughly fifteen minutes and slightly elevated for several hours nonetheless these subsequent price adjustments are basically independent of the first minute s return we identify those announcements with the greatest impact on these markets we examine the impact on interest rate and foreign exchange markets of scheduled macroeconomic news releases such as the employment report the consumer price index cpi and the producer price index ppi many market participants believe that such announcements have a major impact on financial markets indeed a small industry devoted to predicting the figures to be released in upcoming releases has evolved in recent years with the exception of the weekly money supply figures however the impact of such announcements on financial markets has received scant attention 1 this is doubly surprising given the considerable research interest in market volatility since these news releases are a potential source of much of this volatility consider for instance figure 1 as shown there prices in interest rate and foreign exchange futures markets are much more volatile between 8 30 and 8 35 a m eastern time et than during any other five minute trading period including

price equilibrium and willingness to pay in a vertically differentiated mixed duopoly in the framework of a vertically differentiated mixed duopoly with uncovered market and zero costs we study the existence of a price equilibrium when a welfare maximizing public firm producing low quality goods competes against a profit maximizing private firm producing high quality goods we show that a price equilibrium exists if the quality spectrum is wide enough vis a vis a measure of the convexity of the distribution of the consumers willingness to pay and that such equilibrium is unique if this sufficient condition is tightened logconcavity of the income distribution is inconsistent with the existence of equilibrium

the effects of trading halts on price discovery for nyse stocks this article uses intraday data for the year 1992 to investigate the effect of trading halts on price discovery for stocks traded on the new york stock exchange the results show that the degree of benefits from trading halts depends on the types of halts and significance of the news items it is found that trading halts reduce price dispersion when trading is halted due to imbalance in order flows such a positive effect is robust to the significance of news items trading halts can help price discovery when trading is halted due to the fact that some significant news items already hit the market and investors need more time to digest the impacts on price in contrast when officials call for the halt due to the pending news release with little significance trading halts actually inject more noise into the prices and undermine the price discovery process overall the results are consistent with the argument by exchanges that trading halts help dissipate information and facilitate the price discovery pr

predicting volatility in the foreign exchange market measures of volatility implied in option prices are widely believed to be the best available volatility forecasts in this article we examine the information content and predictive power of implied standard deviations isds derived from chicago mercantile exchange options on foreign currency futures the article finds that statistical time series models even when given the advantage of ex post parameter estimates are outperformed by isds isds however also appear to be biased volatility forecasts using simulations to investigate the robustness of these results the article finds that measurement errors and statistical problems can substantially distort inferences even accounting for these however isds appear to be too variable relative to future volatility it is widely believed that the volatility implied in option prices is the market s best estimate of future volatility after all if it were not one could devise a trading strategy that could generate profits by identifying mispriced options the purpose of this article is to investigate the information content and predictive power of volatility implied in options on foreign currencies the paper focuses on options on currency futures traded on the chicago mercantile exchange cme because of the depth and liquidity of cme futures and options traded side by side in the same market implied standard deviations isds allow for clean tests of the predictive power of implied volatilities early studies of the information content of isds have generally found that these contain substantial information for future volatility latane and rendleman 1976 chiras and manaster 1978 and beckers 1981 for example regress future volatility on the weighted implied volatility across a broad sample of chicago board options exchange cboe stocks and find that options contain volatility forecasts that are more accurate than historical measures 1 these studies performed shortly after the 1973 beginning of the cboe option market could only use a relatively short time span and therefore focused on cross sections rather than time series predictions

stock market structure and volatility the procedure for opening stocks on the nyse appears to affect price volatility an analytical framework for assessing the magnitude of the structurally induced volatility is presented the ratio of variance of open to open returns to closeto close returns is shown to be consistently greater than one for nyse common stocks during the period 1982 through 1986 tbe greater volatility at the open is not attributable to the way in which public information is released since both the opento open return and the close to close return span the same period of time instead the greater volatility appears to be attributable to private information revealed in trading and to temporaryprice deviations induced by specialist and other traders the implied cost of immediacy at the open is significantly higher than at the close other empirical evidence in this article documents the volume of trading at the open the time delays between the exchange opening and the first transaction in a stock the difference in daytime volatility versus overnight volatility and the extent to which volatility is related to trading volume

difference form contests and the robustness of all pay auctions abstract in much of the existing literature on rent seeking games the outcome of the contest is either infinitely sensitive or relatively insensitive to contestants efforts the current paper presents a family of contest games that permit characterization of equilibrium for all levels of sensitivity of the outcome to contestants efforts specifically the outcome of the contest depends on the difference between efforts which encompass the lottery and the all pay auction as polar cases the equilibrium converges to that of the all pay auction as the probability of winning the prize grows infinitely sensitive to one s effort and the main qualitative features of equilibrium persist over a large parameter region journal of economic literature classification numbers d44 d72

analysis of the term structure of implied volatilities from various empirical work it is well known that the volatility of asset returns changes over time this might be one of the reasons that implied volatilities differ for options that only differ in time to maturity we construct models for the relation between short and long term implied volatilities based on three different assumptions of stock return volatility behavior i e mean reverting garch and egarch models we test these relations on option price data and conclude that egarch gives the best description of asset prices and the term structure of options implied volatilities

options based forecasts of futures prices in the presence of limit moves the reported analysis examines a simultaneous estimation option based approach to forecast futures prices in the presence of daily price limit moves the procedure explicitly allows for changing implied volatilities by estimating the implied futures price and the implied volatility simultaneously using futures and futures options data for three agricultural commodities it is found that the simultaneous estimation approach accounts for the abrupt changes in implied volatility associated with limit moves and generates more accurate price forecasts than conventional methods that rely on only one implied variable

optimal contracts for teams in a team subject to both adverse selection each member s ability is known only to himself and moral hazard effort cannot be observed optimal contracts are under certain conditions linear in the team s output the outcome is the same whether the principal observes just the total output or each individual s contribution thus monitoring is not needed to prevent shirking by team members instead the role of monitoring is to discipline the monitor production is a collective enterprise by workers in a firm or firms in a joint venture the synergy that is the reason for the team s existence may mean that an individual s contribution to the team s output is not distinguishable so that it is impossible to pay him according to his own productivity how should the principal remunerate the team members so as to maximize his own profit in this paper we analyze incentives in teams with asymmetric information both adverse selection each member s ability is known only to himself and moral hazard effort cannot be observed directly holmstrom 1982 showed that in a team model with moral hazard the principal can ensure an outcome arbitrarily close to the full information ideal by using a contract that punishes each team member arbitrarily severely whenever team output falls below some target however this seems to be an unrealistically drastic way of solving the moral hazard problem in our model we in effect prevent the principal from using such a contract by introducing adverse selection in addition to moral hazard and by assuming that ability and effort interact in such a way that the principal is unable to disentangle an agent s effort from his ability under the assumption that the principal and the team members are risk neutral we shall show that the principal can implement his information constrained optimum simply by offering each agent a payment linear in the team s output although the essential feature of our analysis is the interaction between adverse selection and moral hazard this result can be understood by first considering the special case in which the agents abilities are common knowledge in this case the moral hazard problem can be completely solved the principal can do as well as he

trading and liquidity on the tokyo stock exchange a bird s eye view the trading mechanism for equities on the tokyo stock exchange tse stands in sharp contrast to the primary mechanisms used to trade stocks in the united states in the united states exchange designated specialists have affirmative obligations to provide continuous liquidity to the market specialists offer simultaneous and tight quotes to both buy and sell and supply sufficient liquidity to limit the magnitude of price changes between consecutive transactions in contradistinction the tse has no exchange designated liquidity suppliers instead liquidity is provided through a public limit order book and liquidity is organized through restrictions on maximum price changes between trades that serve to slow down trading in this article we examine the efficacy of the tse s trading mechanisms at providing liquidity our analysis is based on a complete record of transactions and best bid and best offer quotes for most stocks in the first section of the tse over a period of 26 months we study the size of the bid ask spread and its cross sectional and intertemporal stability intertemporal patterns in returns volatility volume trade size and the frequency of trades and market depth based on the response of quotes to trades and the frequency of trading halts and warning quotes the trading mechanism for equities on the tokyo stock exchange tse stands in sharp contrast to the primary mechanisms used to trade stocks in the united states in the united states exchange designated specialists have affirmative obligations to provide continuous liquidity in the market and to maintain a private limit order book with the public s limit orders on the tse exchange designated intermediaries saitori log limit orders and match them to incoming market orders but provide no market making services in the united states specialists offer simultaneous and tight quotes to both buy and sell on the tse public limit orders constitute the available bids and offers in the united states specialists supply sufficient liquidity to limit the magnitude of price changes between consecutive transactions 1 on the tse the market mechanism places limits on the magnitude of consecutive price

toward an economic theory of leadership leading by example this paper explores leadership within organizations leadership is distinct from authority because following a leader is a voluntary rather than coerced activity of the followers this paper considers how a leader induces rational agents to follow her in situations when the leader has incentives to mislead them copyright 1998 by american economic association

strategic incentives in teams implications of returns to scale this article demonstrates the critical relationship between the characteristics of the production function and the strategic incentives in a team equilibrium effort increases in team size when substitutability is low relative to returns to scale effort levels are actually strategic complements when returns to scale exceed the substitutability of members effort moreover even with equal shares the well known problem is determined by returns to scale and becomes worse as returns increase while a target scheme can support the optimal output level as an equilibrium it does not completely deter free riding a team member will accommodate shirking by increasing their own effort within a remarkably large accommodation zone where the additional effort cost is less than the bonus this accommodation of shirking by others exists for different returns to scale and even for very low levels of substitutability

price limit performance evidence from the tokyo stock exchange price limit advocates claim that price limits decrease stock price volatility counter overreaction and do not interfere with trading activity conversely price limit critics claim that price limits cause higher volatility levels on subsequent days volatility spillover hypothesis prevent prices from efficiently reaching their equilibrium level delayed price discovery hypothesis and interfere with trading due to limitations imposed by price limits trading interference hypothesis empirical research does not provide conclusive support for either positions we examine the tokyo stock exchange price limit system to test these hypotheses our evidence supports all three hypotheses suggesting that price limits may be ineffective

option pricing of earnings announcement risks this paper uses option prices to learn about the equity price uncertainty surrounding information released on earnings announcement dates to do this we introduce reduced form models and estimators to separate price uncertainty regarding earnings announcements from normal day to day volatility empirically we find strong support for the importance of earnings announcements we find that the anticipated price uncertainty is quantitatively large varies across time and is informative about the future return volatility finally we quantify the impact of earnings announcements on formal option pricing models

capturing all the information in foreign currency option prices solving for one versus two implied variables the information content of option prices has traditionally been expressed in an implied volatility parameter which is characterized as capturing the markets expectations about future volatility of the underlying asset researchers normally solve for an implied volatility alone a more recent trend has been to solve for both an implied interest rate and standard deviation simultaneously this study compares the proficiency of these two techniques in capturing the information in the market prices of foreign currency options the results show that solving for two implied variables consistently yields less information than solving for an implied volatility alone this raises the implication that by trying to reduce one source of bias by solving for two variables simultaneously researchers may be introducing a more serious source of error resulting in a dilution of the available information

the limitation of monotonicity property of option prices an empirical evidence many option pricing models are based on the assumption that the underlying asset price follows one dimensional diffusion process an alternative approach is to test the properties that should hold for all models based on a given stochastic process for the underlying asset following perignon 2006 we test the empirical validity of the monotonicity property for option prices by collecting all transaction data from 1 july 2006 to 31 december 2006 for option contracts traded on the taiwan futures exchange taifex we find that sampled intraday option prices violate the monotonicity property between 29 97 and 57 of the time and that call and put prices often increase or decrease together we also find evidence to show that the frequent violations of the monotonicity property are to a large extent attributable to microstructure effects and that they arise from rational trading tactics

examining the effectiveness of price limits in an artificial stock market abstract this paper proposes an agent based framework to examine the effectiveness of price limits in an artificial stock market the market is composed of many boundedly rational and heterogeneous traders whose learning behavior is represented by a genetic programming algorithm we calibrate the model to replicate several stylized facts observed in real financial markets based on this environment the impacts of price limits are analyzed from the perspectives of volatility price distortion volume and welfare we find that the imposition of price limits possesses both positive and negative effects however compared with the market without price limits appropriate price limits help to reduce volatility and price distortion and increase the liquidity and welfare

efficiency in sequential partnerships abstract we consider sequential partnerships in which agents obtain non verifiable information about the actions taken by previous agents for such partnerships a budget balanced sharing rule exists that induces efficient production the sharing rule has many desirable features 1 it uniquely implements efficient production 2 it does not rely on message games 3 it does not rely on unlimited liability and 4 it is robust to renegotiation the rule is furthermore simple intuitive and robust to sabotage coalition formation and noise it also induces efficient production when agents obtain incomplete information about previous actions journal of economic literature classificationnumbers d82 l23

partial privatization in mixed duopoly abstract we investigate a quantity setting duopoly involving a private firm and a privatized firm jointly owned by the public and private sectors the private firm maximizes profits while the privatized firm takes both profits and social welfare into consideration we consider how many shares the government should hold in the privatized firm we find that neither full privatization the government does not hold any shares nor full nationalization the government holds all of the shares is optimal under moderate conditions

stock market crashes and the performance of circuit breakers empirical evidence this study examines the behavior of a small stock market with circuit breakers and with a one hour preauction order imbalance disclosure during the october 1987 crash the crash and its aftershocks lasted for a week and selling pressure was concentrated in higher beta larger capitalization and lower leverage firm stocks circuit breakers when implemented reduced the next day opening order imbalance and the initial price loss however they had no effect on the long run response some price overreaction and reversal phenomena also are documented

fighting city hall entry deterrence and technology upgrades in cable tv markets this article investigates how private firms respond to potential entry from public firms this paper uses a data set of over 3 000 u s cable tv systems to present evidence consistent with entry deterrence incumbent cable tv firms upgrade faster when located in markets with a potential municipal entrant however the same systems are then slower to offer new products enabled by the upgrade suggesting upgrades in these markets occur for strategic reasons incumbent cable systems also upgrade faster in response to municipal entry threats than to private entry threats understanding how private firms respond to potential entry from public firms is especially important in light of recent u s government entry into several industries this paper was accepted by bruno cassiman business strategy

output and wages with inequality averse agents we analyze a two task work environment with risk neutral but inequality averse individuals for the agent employed in task 2 eort is verifiable while in task 1 it is not accordingly agent 1 receives an incentive contract which due to his wealth constraint leads to a rent that the other agent resents we show that greater inequality aversion unambiguously decreases total output and therefore average labor productivity more specifically inequality aversion reduces eort wage

the relation between price changes and trading volume a survey this paper reviews previous and current research on the relation between price changes and trading volume in financial markets and makes four contributions first two empiri cal relations are established volume is positively related to the magnitude of the price change and in equity markets to the price change per se second previous theoretical research on the price volume relation is summarized and critiqued and major insights are emphasized third a simple model ofthe price volume relation is proposed that is consis tent with several seemingly unrelated or contradictory observations and fourth several directions for future research are identified

speculative markets and the effectiveness of price limits abstract the aim of this paper is to study the effectiveness of price limits in speculative markets we construct a nonlinear stochastic asset pricing model in which traders rely on technical and fundamental analysis to determine their orders the dynamics of the model mimic stylized facts such as the emergence of bubbles excess volatility fat tails for returns or volatility clustering quite well using this model as a laboratory we find that price limits have the potential to reduce both volatility and deviations from fundamentals the more traders lend themselves to trend extrapolating behavior the better price limits work

stock splits volatility increases and implied volatilities a test of the efficiency of the chicago board options exchange relative to post split increases in the volatility of common stocks is presented the black scholes and roll option pricing formulas are used to examine the behavior of implied standard deviations isds around split announcement and ex dates comparisons with a control group of stocks find no relative increase in isds of stocks announcing splits however a relative increase is detected at the ex date therefore the joint hypothesis that 1 the blackscholes and roll formulas are true and 2 the cboe is efficient can be rejected recent studies by ohlson and penman 1985 dravid 1984 and dubofsky and french 1985 have documented significant increases in the observed variance of common stock returns subsequent to splits larger than 25 this is surprising because in theory no real event is associated with the actual day of the split dravid 1988 and lim and vijh 1986 have tried to explain the postsplit variance increase as the effect of stock price discreteness and the bid ask spread the evidence in lim and vijh 1986 and ohlson and penman 1985 suggests however that this is at best a partial explanation 2 although the causes of the volatility increase are not apparent the post split volatility increase should increase prices of calls on the splitting stock that expire after the ex date relative to those that expire before the ex date similarly prices of post split expiration calls on splitting stocks should increase relative to prices of calls on stocks that do not split in an efficient options market these relative price changes should occur at the announcement of the split in fact

order imbalances and stock price movements on october 19 and 20 1987 on october 19 1987 nyse stocks in the s p index declined seven percentage points more than nyse stocks not in this index in the first hour of trading on october 20 the s p stocks virtually recovered to the level of the non s p stocks there is a strong relation between order imbalances and stock price movements both in analyses of time series and cross sections thus in addition to the breakdown in the linkage between future prices and the spot index on these two days there were also breakdowns in the linkage among nyse stocks

the valuation of options on futures contracts rational restrictions are derived for the values of american options on futures contracts for these options the optimal policy in general involves premature exercise a model is developed for valuing options on futures contracts in a constant interest rate setting despite the fact that premature exercise may be optimal the value of this american feature appears to be small and a european formula due to black serves as a useful approximation finally a model is developed to value these options in a world with stochastic interest rates it is shown that the pricing errors caused by ignoring the location of the interest rate relative to its long run mean range from 5 to 7 when the current rate is 200 basis points from its long run value the role of interest rate expectations is therefore crucial to the valuation optimal exercise policies are found from numerical methods for both models in recent years there has been a steady growth in the number of financial assets which one might properly call derivative assets that are available for trading on the organized exchanges among these the most recent and notable are options contracts written on available futures contracts options are now traded on the futures contracts on stock market indexes on the futures contracts on treasury instruments on the futures contracts on foreign exchange rates and on the futures contracts on some metals in design these options contracts do not differ substantially from the well known options contracts on common stock except that the underlying asset is a futures contract the received theory of the valuation of these options suggests that such contracts provide a direct vehicle for investors to alter the terminal payoffs on their portfolios to a desired distribution in the absence of these contracts investors would be forced to pursue a dynamic portfolio policy at the expense of considerable transactions in order to achieve a similar distribution indeed the availability of put options on the futures contracts on stock market indexes now enables well diversified investors to purchase portfolio insurance in his seminal work black 1 provided a complete description of forward and futures contracts as well as the description and valuation of european options on forward contracts and on spot commodities breeden 3 has examined the use of commodity options in a theoretical framework and courtadon 6 has studied the valuation of options on treasury bond futures french 13 cox

mixed oligopoly equilibria when firms objectives are endogenous abstract we study a vertically differentiated market where two firms simultaneously choose the quality and price of the good they sell and where consumers may also care for the average quality of the goods supplied firms are composed of two factions whose objectives differ one is maximizing profit while the other maximizes revenues the equilibrium concept we model called firm unanimity nash equilibrium fune corresponds to the nash equilibrium between firms when there is efficient bargaining between the two factions inside both firms we first show that such equilibria are inefficient with both firms underproviding quality we then assume that the government takes a participation in one firm which introduces a third faction bent on welfare maximization in that firm we study the characteristics of equilibria as a function of the bargaining weight of the welfare maximizing faction we show that equilibrium welfare increases with this bargaining weight especially if consumers care a lot for the average quality of the goods provided

the creation and resolution of market uncertainty the impact of information releases on implied volatility we model and examine the impact of information releases on market uncertainty as mea sured by the implied standard deviation isd from option markets distinguishing between scheduled and unscheduled announcements we hypothesize that since the timing although not the content of scheduled announcements is known a priori the pre release isd will impound the anticipated impact of important releases on price volatility and that the isd will normally decline post release as this uncertainty is resolved conversely we hypothesize that the unexpected high volatility caused by major unscheduled releases will cause market participants to adjust upward their estimates of likely volatility over the remaining life of the option resulting in an increase in the isd our evidence supports both hypotheses the isds that we consider are from the t bond eurodollar and deutschemark options markets we examine scheduled macroeconomic news releases such as the employment report and the ppi we also find that the observed tendency for the isd to fall on fridays and rise on mondays is due to the weekday pattern of scheduled news releases

capacity investment timing by start ups and established firms in new markets we analyze the competitive capacity investment timing decisions of both established firms and start ups entering new markets which have a high degree of demand uncertainty firms may invest in capacity early when uncertainty is high or late when uncertainty has been resolved possibly at different costs established firms choose an investment timing and capacity level to maximize expected profits whereas start ups make those choices to maximize the probability of survival when a start up competes against an established firm we find that when demand uncertainty is high and costs do not decline too severely over time the start up takes a leadership role and invests first in capacity whereas the established firm follows by contrast when two established firms compete in an otherwise identical game both firms invest late we conclude that the threat of firm failure significantly impacts the dynamics of competition involving start ups this paper was accepted by yossi aviv operations management

foreign exchange option prices as predictors of equilibrium forward exchange rates abstract this study investigates empirically the efficiency of the forward foreign exchange market by using exchange rates implied from currency option prices to signal trading strategies in 30 day forward contracts the proportional deviation between implied and simultaneously observed exchange rates is found to be a direct and statistically significant determinant of subsequent returns on forward contract holdings however an ex ante trading rule test reveals that the additional information impounded in currency option prices is insufficient to generate statistically economic profits

a transaction data study of weekly and intradaily patterns in stock returns abstract weekly and intradaily patterns in common stock prices are examined using transaction data for large firms negative monday close to close returns accrue between the friday close and the monday open for smaller firms they accrue primarily during the monday trading day for all firms significant weekday differences in intraday returns accrue during the first 45 minutes after the market opens on monday mornings prices drop while on the other weekday mornings they rise otherwise the pattern of intraday returns is similar on all weekdays most notable is an increase in prices on the last trade of the day

the pricing of japanese equity warrants discrepancies between the black scholes value of japanese equity warrants and their observed prices are explained in part by the stochastic volatility of changes in prices of the underlying stocks we fit garch and egarch models to the stochastic volatility and briefly compare their performance to the cev model a hopscotch algorithm is used to value the warrants in the presence of the stochastic stock price volatility the stochastic volatility hopscotch warrant values still differ substantially from corresponding prices in contrast away from the money short term nikkei 225 options valued with the same stochastic volatility models are close to observed prices a regression model is used to fit the differences between warrant values and prices as a function of proxies for market impediments

standard deviations implied in option prices as predictors of future stock price variability abstract standard deviations implied in option prices have recently been introduced as being better than average predictors of future stock price variability this article specifically studies the predictive ability of implicit standard deviations taking into account the dividend problem and the problem of optimal weighting schemes of the standard deviations when there are several options on the same stock transaction data information was used to study the importance of non simultaneities in observing stock and option prices

policy objectives and performance in a mixed market with bargaining abstract we analyse a mixed duopoly in which wages and salaries are determined by nash bargaining and where the public firm s unit costs depend on its objectives because of constant returns to scale welfare maximisation without restriction would eliminate or significantly weaken the private firm therefore we focus on constrained welfare maximisation in which case unit costs are normally higher in the public firm on the other hand the private firm may even earn more than in a monopoly if the public firm maximises profits or if the constraint offers too much protection

duopoly and quality standards abstract in the absence of sunk costs a low quality producer benefits from a mildly restrictive quality standard whereas a high quality producer suffers from it consumers welfare increases if the firm producing the higher quality does not increase its quality significantly in response to the increase in quality by its rival a sufficiently severe standard causes exit from the industry when there are no sunk cost the high quality producer exits first

a theory of price limits in futures markets abstract the existence of price limits in certain futures markets is explained by demonstrating that price limits may act as a partial substitute for margin requirements in ensuring contract performance their effectiveness is a decreasing function of the amount of information available to traders about the equilibrium futures price which is unobservable in the event of a limit move and the theory predicts that no limits will exist in the markets for financial futures actual limits are broadly consistent with the theory his interpretation plausible as it was was totally misleading with the dangerous verisimilitude of a theory which will fit all or nearly all the facts and yet more entirely miss the truth by a mere accident then would a frank perplexity heritage v sackville west