supply chain relationships and contracts the impact of repeated interaction on capacity investment and procurement consider a firm developing an innovative product due to market pressures production must begin soon after the product development effort is complete which requires that an upstream supplier invests in capacity while the design of the product and production process are in flux because the product is ill defined at this point in time the firms are unable to write court enforceable contracts that specify the terms of trade or the supplier s capacity investment however the firms can adopt an informal agreement relational contract regarding the terms of trade and capacity investment the potential for future business provides incentive for the firms to adhere to the relational contract we show that the optimal relational contract may be complex requiring the buyer to order more than her demand to indirectly monitor the supplier s capacity investment we propose a simpler relational contract and show that it performs very well for a broad range of parameters finally we identify characteristics of the business environment that make relational contracting particularly valuable

optimal pricing and return policies for perishable commodities this paper considers the pricing decision faced by a producer of a commodity with a short shelf or demand life a hierarchical model is developed and the results of the single period inventory model are used to examine possible pricing and return policies the paper shows that several such policies currently in effect are suboptimal these include those where the manufacturer offers retailers full credit for all unsold goods or where no returns of unsold goods are permitted the paper also demonstrates that a policy whereby a manufacturer offers retailers full credit for a partial return of goods may achieve channel coordination but that the optimal return allowance will be a function of retailer demand therefore such a policy cannot be optimal in a multi retailer environment it is proven however that a pricing and return policy in which a manufacturer offers retailers a partial credit for all unsold goods can achieve channel coordination in a multi retailer environment this article was originally published in marketing science volume 4 issue 2 pages 166 176 in 1985

planning under incomplete information and the ratchet effect abstract central planning of production is usually performed under asymmetric information the firm in general has more information about its productive possibilities than the central planner from now on for short cp this justifies the use of incentives schemes in which the cp does not directly fix activity levels casual observation of such existing schemes suggests that the time dimensions is crucial for their working typically the cp revises the incentive scheme over time to take into account the information provided by the firm s performance managers of centrally planned economies as well as economists have long recognized that this revision induces firms to underproduce in order to avoid demanding schemes in the future this is the ratchet effect it is purpose of the present paper to study the ratchet effect under the non commitment assumption which we believe to be more realistic the inadequacy of conceptual tools made if difficult in the past to consider such an assumption now basic research on dynamic games with incomplete information recently resulted in new ideas which look particularly relevant for a theoretical analysis of the problem

designing supply contracts contract type and information asymmetry this paper studies the value to a supplier of obtaining better information about a buyer s cost structure and of being able to offer more general contracts we use the bilateral monopoly setting to analyze six scenarios three increasingly general contracts wholesale pricing schemes two part linear schemes and twopart nonlinear schemes each under full and incomplete information about the buyer s cost structure we allow both sides to refuse to trade by explicitly including reservation profit levels for both for the supplier this is implemented through a cutoff policy we derive the supplier s optimal contracts and profits for all six scenarios and examine the value of information and of more general contracts our key findings are as follows first the value of information is higher under two part contracts second the value of offering two part contracts is higher under full information and third the proportion of buyers the supplier will choose to exclude can be substantial

an empirical test of a valuation model for american options on futures contracts pricing models for american call and put options on futures contracts are derived herein these models are used to investigate the efficiency of the market for options on standard poor 500 and german mark futures the evidence presented here indicates that market prices for these options deviate substantially from their corresponding model prices in addition it is shown that a hedging strategy originated at prices that indicate a deviation of market from model is successful in translating the observed mispricing into excess profits after transactions costs however these net profits are eliminated if the origination of the strategy is delayed by one trade or if bid ask spreads are accounted for

price setting supergames with capacity constraints this paper examines the role of industry capacity in enforcing collusion in the context of repeated games for a fixed capacity per firm it is shown that changes in the number of firms have a non monotone effect on the best enforceable cartel price this is due to the fact that while an additional firm lowers the share that each of the other firms enjoys at the collusive price it also increases the losses to each firm should the cartel fail

capacity constraints mergers and collusion abstract the objective of this paper is two fold to contribute to the analysis of tacit collusion in bertrand supergames with asymmetric capacity constraints and from a more applied perspective to bring a new light on merger analysis and provide useful guidelines for competition policy taking into account dynamic aspects of competition it is well known that capacity constraints affect tacit collusion as they limit both incentives to deviate e g to undercut rivals and retaliation possibilities however most studies have so far focused on symmetric situations where all firms have the same capacity which leads to ambiguous and unintuitive results and also considerably limits the scope of application studying asymmetric situations makes it possible to analyse the impact of changes in the distribution of these capacities expansions but also mergers split offs transfers etc and to provide guidelines for competition policy and particularly for merger policy these guidelines which differ substantially from those inspired by more static analyses such as the herfindahl or other standard concentration tests are applied to a famous merger that took place in the french bottled water market the nestle perrier merger case

pricing and trading european options by combining artificial neural networks and parametric models with implied parameters we compare the ability of the parametric black and scholes corrado and su models and artificial neural networks to price european call options on the s p 500 using daily data for the period january 1998 to august 2001 we use several historical and implied parameter measures beyond the standard neural networks in our analysis we include hybrid networks that incorporate information from the parametric models our results are significant and differ from previous literature we show that the black and scholes based hybrid artificial neural network models outperform the standard neural networks and the parametric ones we also investigate the economic significance of the best models using trading strategies extended with the chen and johnson modified hedging approach we find that there exist profitable opportunities even in the presence of transaction costs

arbitrage continuous trading and margin requirements this paper studies the impact that margin requirements have on both the existence of arbitrage opportunities and the valuation of call options in the context of the blackscholes economy margin restrictions are shown to exclude continuous trading arbitrage opportunities and with two additional hypotheses still to allow the black scholes call model to apply the black scholes economy consists of a continuously traded stock with a price process that follows a geometric brownian motion and a continuously traded bond with a price process that is deterministic continuous trading security market models constitute a significant area of continuing reesearch in financial economics these models form the basis of the option pricing methodology see merton 16 for a review and current intertemporal asset pricing models see merton 15 breeden 3 and cox ingersoll and ross 5 given the importance of these models it is of no surprise that there has been significant academic concern see dybvig 9 cox ingersoll and ross 4 p 341 and ingersoll 13 pp 13 25 over the discovery of a continuous trading strategy by harrison and kreps 10 called the doubling strategy that generates a sure dollar from a zero investment the existence of this doubling strategy violates a basic premise of the option pricing methodology the premise of no arbitrage opportunities given this violation the question naturally arises as to whether the option pricing methodology is internally consistent fortunately harrison and pliska 11 showed that the exclusion of arbitrage opportunities and the doubling strategy does not invalidate the familiar derivation of the black scholes call option formula the exogenous exclusion of these doubling strategies is somewhat arbitrary however types of constraints that exclude continuous trading arbitrage opportunities were studied by kreps 14 harrison and kreps 10 and dybvig 9 these papers provide constraints that are unsatisfactory from an institutional point of view since they have no market analogue margin requirements on the other hand have a market analogue one purpose of this paper is to show that margin requirements also exclude continuous trading arbitrage opportunities to make this argument self contained we first provide a unified framework that synthesizes the previously stated results our assertion concerning margin re

empirical studies of financial innovation lots of talk little action this paper reviews the extant empirical studies of financial innovation adopting broad criteria we could find only somewhat more than two dozen studies and since some financial innovations are examined by more than one study they cover only seventeen phenomena especially striking is the fact that only two studies offer tests of the broad hypotheses concerning the environmental conditions spurring financial innovation e g regulation taxes unstable macroeconomic conditions and ripe technologies that have been advanced in descriptive articles we offer some tentative conjectures as to why empirical studies of financial innovation are comparatively rare among our suggested culprits is an absence of accessible data we urge financial regulators to undertake more surveys of financial innovation and to make the survey data more available to researchers

the price of anarchy in supply chains quantifying the efficiency of price only contracts in this paper we quantify the efficiency of decentralized supply chains that use price only contracts with a price only contract a buyer and a seller agree only on a constant transaction price without specifying the amount that will be transferred it is well known that these contracts do not provide incentives to the parties to coordinate their inventory capacity decisions we measure efficiency with the price of anarchy poa defined as the largest ratio of profits between the integrated supply chain that is fully coordinated and the decentralized supply chain we characterize the efficiency of various supply chain configurations push or pull inventory positioning two or more stages serial or assembly systems single or multiple competing suppliers and single or multiple competing retailers

optimal dynamic information provision abstract we study a dynamic model of information provision a state of nature evolves according to a markov chain an advisor with commitment power decides how much information to provide to an uninformed decision maker so as to influence his short term decisions we deal with a stylized class of situations in which the decision maker has a risky action and a safe action and the payoff to the advisor only depends on the action chosen by the decision maker the greedy disclosure policy is the policy which at each stage minimizes the amount of information being disclosed in that stage under the constraint that it maximizes the current payoff of the advisor we prove that the greedy policy is optimal in many cases but not always

trader rationality in the exercise of futures options abstract we examine the rationality of investor exercise behavior by analyzing two years tendered exercise notices for treasury bond futures options we conclude that exercise behavior is generally rational but document numerous failures to exercise as well as some exercises that should not have occured both at and prior to expiration the most frequent type of error is failing to exercise suggesting that traders do not monitor their positions with sufficient care finally we show that investors use information arriving after trading closes but before exchange imposed exercise deadlines in forming their exercise decisions

financial innovations and arbitrage pricing in economies with frictions revisited abstract existing literature points to the role of market frictions in providing motivations for financial innovations in this paper we study the effectiveness of the arbitrage pricing approach and the design and pricing of innovated securities in economies with restrictions on short sales in the process we also define the no arbitrage conditions that is appropriate for such economies the differences between our results and chen s 3 are pointed out when appropriate journal of economic literature classification numbers c61 g10 g12 g20

the effects of transaction costs and different borrowing and lending rates on the option pricing model a note this paper modifies the black scholes option pricing model to include the effects of transaction costs and different borrowing and lending rates the paper demonstrates that these market imperfections tend to offset each other yielding a bounded range of prices for each option the paper also shows that under some conditions the option pricing hedge may be society s lowest cost financial intermediary

excess capacity and collusion in this paper the authors analyze a restricted class of equilibria in the dynamic model of j p benoit and v krishna 1987 in which firms choose their scale of operation before engaging in a repeated game of price competition benoit and krishna established that all firms carry excess capacity in all collusive equilibria as the authors are interested in the relationship between excess capacity and collusion in price they examine equilibria in which firms tacitly collude in price but not in investment decisions copyright 1990 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

the pricing of convexity risk and timedecay in options markets abstract option valuation formulas typically assume all risk can be eliminated in a continuously rebalanced hedge but convexity of the option pricing function and time decay cause risk in real world hedges we find strong evidence in stock options transactions data from periods 10 years apart that the market prices these risks there is a significant price effect associated with convexity that becomes larger immediately following a period of larger stock price movements although time decay is highly correlated with convexity a multiple regression including both factors shows it to have a significant independent effect the results from the two sample periods are highly consistent as are pre and post crash results from the year 1987

to commit or not to commit revisiting quantity vs price competition in a differentiated industry previous studies have shown that quantity commitment by all firms in an industry mitigates price competition this paper shows that when firms have a choice asymmetric outcomes can arise with some firms choosing to commit to a quantity and other firms choosing not to to study the commitment decision we analyze a multistage game within a duopoly of differentiated firms a la hotelling in the first stage of the game firms choose whether or not to commit to a quantity in the second stage each firm that chose to commit sets a quantity which represents an upper bound on how much it can sell to consumers in the third stage both firms set prices strategically regardless of whether or not they committed in the final stage demand is allocated as consumers maximize their utilities firm s that chose not to commit to a quantity in the first stage can fulfill any quantity that consumers demand at the equilibrium prices we find that if product differentiation is sufficiently low both firms choose to co

the weekend effect on the distribution of stock prices abstract evidence of weekend effects on the distribution of security returns suggests that returns are generated by a process operating closer to trading time rather than calendar time in contrast accumulation of interest over the weekend follows a calendar time process since both the variance of returns and the interest rate are important parameters of the black scholes option pricing model this paper suggests that the model be stated to account for this by utilizing a trading time variance and a calendar time interest rate empirical evidence indicates that this allows the model to better explain market option prices

the principle of minimum differentiation revisited abstract hotelling s model of differentiated products is examined and modified so that consumers have relatively low reservation prices for the differentiated products the problem of existence of a nash equilibrium in prices in a duopoly with given products is analysed when the reservation price is relatively low a nash equilibrium in prices exists for a larger range of products than when the reservation price is infinite next i examine product competition with instantaneous adjustment to the nash equilibrium prices of the previous game firms competing in a nash fashion have tendencies to move away from each other and try to achieve local monopolistic positions this is in sharp contrast with the acclaimed principle of minimum differentiation of the original model of hotelling of high reservation price where firms clustered in the product space

dynamic bargaining in a supply chain with asymmetric demand information we analyze a dynamic bargaining game in which a seller and a buyer negotiate over quantity and payment to trade for a product both firms are impatient and they make alternating offers until an agreement is reached the buyer is privately informed about his type which can be high or low the high type s demand is stochastically larger than the low type s in the dynamic negotiation process the seller can screen whereas the buyer can signal information through their offers and the buyer has an endogenous and type dependent reservation profit with rational assumptions on the seller s belief structure we characterize the perfect bayesian equilibrium of the bargaining game interestingly we find that both quantity distortion and information rent may be avoided depending on the firms relative patience and the seller may reach an agreement with either the high type or the low type first or with both simultaneously furthermore we explore our model to characterize the effect of demand forecasting accuracy on firm profitability we find that improved demand forecast benefits the buyer but hurts the seller when the buyer s forecasting accuracy is low however once the buyer s forecasting accuracy exceeds a threshold both firms will benefit from further improvement of the forecast this observation makes an interesting contrast to previous findings based on the one shot principal agent model in which improvement of forecasting accuracy mostly leads to a win lose outcome for the two firms and the buyer has an incentive to improve his forecasting accuracy only when it is extremely low this paper was accepted by yossi aviv operations management

hedging the risks from writing foreign currency options abstract this paper considers the ways in which banks and other financial institutions can hedge their risks when they write non exchange traded foreign currency options key factors affecting the performance of delta hedging are identified and hedging schemes involving the use of exchange traded options are analyzed the schemes are tested using both simulated data and data from trades on the philadelphia exchange between february 1983 and september 1984

the measurement of option mispricing abstract different studies have examined the ability of the black scholes option pricing model to estimate accurately market prices of publicly traded options and reached conflicting results this study examines commonly used ex ante measures of option mispricing finds that they can produce differing conclusions about option prices and develops an alternative measure for gauging option mispricing empirical analysis of returns to options selected using the various mispricing measures indicates that this new measure is more likely to detect mispricing and identify options that yield excess returns before commissions

comparative performance of the black scholes and roll geske whaley option pricing models the original black scholes bs 2 european call option pricing model does not take account of divided payments on the underlying stock and does not allow for the possibility of early exercise that may be optimal when the stock pays dividends black 1 has suggested that the original bs model can be modified to take account of dividends and sharpe 14 predicts that this modified or pseudo american bs approach while not exact is probably sufficient for many listed options

implied volatilities and transaction costs using data that contain bid and ask quotes for both options and stocks the analysis investigates the constant volatility assumption of the black scholes model the analysis adjusts for bid ask spreads and finds evidence that is inconsistent with the constant volatility assumption instead the results reveal a strong negative correlation between volatility and stock price and they suggest that using a nonconstant volatility model such as the cev model would be more appropriate to price long term options finally transaction costs associated with the dynamic hedge tend to increase with an option s maturity but decrease as a percentage of the option s price

the risk premium of volatility implicit in currency options this article provides an empirical investigation of the risk neutral variance process and the market price of variance risk implied in the foreign currency options market there are three principal contributions first the parameters of heston s mean reverting square root stochastic volatility model are estimated using dollar mark option prices from 1987 to 1992 second it is shown that these implied parameters can be combined with historical moments of the dollar mark exchange rate to deduce an estimate of the market price of variance risk these estimates are found to be nonzero time varying and of sufficient magnitude to imply that the compensation for variance risk is a significant component of the risk premia in the currency market finally the out of sample test suggests that the historical variance and the hull and white implied variance contain no more information than that imbedded in the heston implied variance

information distortion in a supply chain the bullwhip effect this article originally appeared in management science april 1997 volume 43 number 4 pp 546 558 published by the institute of management sciences consider a series of companies in a supply chain each of whom orders from its immediate upstream member in this setting inbound orders from a downstream member serve as a valuable informational input to upstream production and inventory decisions this paper claims that the information transferred in the form of orders tends to be distorted and can misguide upstream members in their inventory and production decisions in particular the variance of orders may be larger than that of sales and distortion tends to increase as one moves upstream a phenomenon termed bullwhip effect this paper analyzes four sources of the bullwhip effect demand signal processing rationing game order batching and price variations actions that can be taken to mitigate the detrimental impact of this distortion are also discussed

multilateral bargaining and downstream competition we examine multilateral bargaining in vertical supply relationships that involve an upstream manufacturer who sells through two competing retailers in these relationships the negotiations are interdependent and bargaining externality may arise across the retailers in addition the timing by which the manufacturer negotiates with the retailers becomes important in simultaneous bargaining the retailers negotiate without knowing if an agreement has been reached in the other retail channel whereas in sequential bargaining the retailer in the second negotiation is able to observe whether an agreement was reached in the first negotiation we show that simultaneous bargaining is optimal for the manufacturer when the retail prices and profitability are similar and sequential bargaining is preferred when the dispersion in the retail prices is sufficiently large as a result of ex post renegotiations the manufacturer may strategically stock out the less profitable retailer who charged a relatively low retail price and exclusively supply only the retailer who charged a relatively high retail price and maintained high channel profitability moreover ex post multilateral bargaining can buffer downstream competition and thus lead to positive retail profits even in markets that are close to perfect competition

adverse selection and renegotiation in procurement as was shown by dewatripont optimal long term contracts are generally not sequentially optimal the parties ex post renegotiate them to their mutual advantage this paper fully characterizes the equilibrium of a simple two period procurement situation and studies the extent to which renegotiation reduces ex ante welfare i a central result is that like in the non commitment case the second period allocation is optimal for the principal conditionally on his posterior beliefs about the agent ii the first period allocation exhibits an increasing amount of pooling when the discount factor grows iii with a continuum of types it is never optimal to induce full separation the paper also analyzes whether renegotiated long term contracts yield outcomes resembling those under either unnegotiated long term contracts or a sequence of short term contracts and it links the analysis with the multiple unit durable good monopoly problem

the relative performance of five alternative warrant pricing models five warrant pricing models are examined in this study a pair based on the black scholes model a pair based on the constant elasticity of variance cev modification and an extendible warrant model a la longstaff based on more than 20 000 warrant price observations the flexible exponent cev model generates the lowest average absolute pricing error in most of the warrants examined the dilution adjusted black scholes model however remains a reasonable economical alternative in many cases

the dynamics of incentive contracts the paper studies a simple two period principal agent model in which the principal updates the incentive scheme after observing the agent s first period performance the agent has superior information about his ability the principal offers a first period incentive scheme and observes some measure of the agent s first period performance cost or profit which depends on the agent s ability and unobservable first period effort the relationship is entirely run by short term contracts in the second period the principal updates the incentive scheme and the agent is free to accept the new incentive scheme or to quit the strategies are required to be perfect and updating of the principal s beliefs about the agent s ability follows bayes rule the central theme of the paper is that the ratchet effect leads to much pooling in the first period first for any first period incentive scheme there exists no separating equilibrium second when the uncertainty about the agent s ability is small the optimal scheme must involve a large amount of pooling the paper also gives necessary and sufficient conditions for the existence of partition equilibria and looks at the effect of cost uncertainty

technical note optimal long term supply contracts with asymmetric demand information we consider a manufacturer selling to a retailer with private demand information arising dynamically over an infinite time horizon under a backlogging model we show that the manufacturer s optimal dynamic long term contract takes a simple form in the first period based on her private demand forecast the retailer selects a wholesale price and pays an associated upfront fee and from then on the two parties stick to a simple wholesale price contract with the retailer s chosen price under a lost sales model we show that the structure of the optimal long term contract combines a menu of wholesale pricing contracts with an option that if exercised by the retailer reduces future wholesale prices in exchange for an immediate payment to the manufacturer the online appendix is available at https doi org 10 1287 opre 2017 1626

sustaining long term supply chain partnerships using price only contracts abstract in this paper we study how an informal long term relationship between a manufacturer and a retailer performs in turbulent market environments characterized by uncertain demand we show that the long term partnership based on repeated interaction is sustainable under price only contracts when the supply chain partners are sufficiently patient that is the channel can be coordinated over a long time horizon when the factor whereby the members discount the future value of this trusting relationship is sufficiently high second above the minimum discount factor a range of wholesale prices exists that can sustain the long term partnership and there are different possible profit divisions between the two players third when the market is turbulent i e either the expected demand or the demand variance changes from period to period according to a probabilistic law it is typically less possible to sustain the long term partnership in a booming market or in a market with low demand variability finally obtaining more information about future market fluctuation may not help the supply chain to sustain the long term partnership due to partners strategic considerations with the availability of the market signal total supply chain profits increase but the retailer may even be worse off

a supplier s optimal quantity discount policy under asymmetric information in the supply chain literature an increasing body of work studies how suppliers can use incentive schemes such as quantity discounts to influence buyers ordering behaviour thus reducing the supplier s and the total supply chain s costs various functional forms for such incentive schemes have been proposed but a critical assumption always made is that the supplier has full information about the buyer s cost structure we derive the optimal quantity discount policy under asymmetric information and compare it to the situation where the supplier has full information

financial innovation the last twenty years and the next the word revolution is entirely appropriate for describing the changes in financial institu tions and instruments that have occurred in the past twenty years the major impulses to successful financial innovations have come from regulations and taxes the outlook for the future is for a slowing down of the rate of financial innovation but much growth and improvement are still in prospect

primes and scores an essay on market imperfections this paper investigates the reported relative mispricing of primes and scores to the underlying stock given transaction costs we establish arbitrage based bounds on prime and score prices we then develop a new nonparametric statistical technique to test whether prime and score prices violate these bounds we find that prime and score prices do exceed stock prices and often by a considerable amount we demonstrate that this increased value is most likely due to the score s ability to save on the costs of dynamic hedging we also show how short sale and trust size constraints impede the ability to arbitrage price disparities in an efficient market the price of a security reflects the value of its underlying assets it should not be possible therefore to create value simply by splitting a security into different parts since the underlying assets are unchanged the packaging of the cash flows should not matter the recent introduction of primes and scores suggests that this is not always the case by separating a security s cash flows into a dividend based component the prime and an appreciation or option based component the score developers of these securities have seemingly created two assets whose value separately exceeds that of the original stock since the prime and the score are based on the same underlying asset this raises a puzzling question about the actual efficiency of securities markets this paper investigates this anomaly by examining whether primies and scores are actuauy mispriced and if so why given the costs of transacting in the prime score and stock we establish bounds on prime and score prices that are consistent with no arbitrage opportunities we then develop a new nonparametric statistical technique to test whether prime and score prices violate these bounds this nonparametric procedure is designed both to confront the measurement error problems plaguing the literature i e nonobservable bid ask prices and nonsimultaneous prices see phillips and smith 1980 bhattacharya 1983 and bookstaber 1981 and to avoid the estimation of round trip transaction costs commissions we find the surprising result that prime and score prices exceed the price of the underlying stock often by a considerable amount using time series data we de monstrate that significant price differentials exist for each firm in our sample

optimal stock trading with personal taxes implications for prices and the abnormal january returns abstract the tax law confers upon the investor a timing option to realize capital losses and defer capital gains with the tax rate on long term gains and losses being about half the short term rate the law provides a second timing option to realize losses short term and gains long term if at all our theory and simulation over the 1962 1977 period establish that taxable investors should realize long term gains in high variance stocks and repurchase stock in order to realize potential future losses short term tax trading does not explain the small firm anomaly but predicts a seasonal pattern in trading volume which maps into a seasonal pattern in stock prices the january anomaly only if investors are irrational or ignorant of the price seasonality

supply chain performance under market valuation an operational approach to restore efficiency based on a supply chain framework we study the stocking decision of a downstream buyer who receives private demand information and has the incentive to influence her capital market valuation we first characterize a market equilibrium under a general single buyback contract we show that the buyer s stocking decision can be distorted in equilibrium such a downstream stocking distortion hurts the buyer firm s own performance and it also influences the performances of the supplier and the supply chain we further reveal scenarios where full supply chain efficiency cannot be reached under any single buyback contract then focusing on contract design we characterize conditions under which a menu of buyback contracts can prevent downstream stocking distortion and restore full efficiency in the supply chain our study demonstrates that in a supply chain context a firm s incentive to undertake real economic activities to influence capital market valuation can potentially be resolved through operational means this paper was accepted by yossi aviv operations management

contract renegotiation and coasian dynamics consider a long term relationship between a seller and a buyer whose valuation for a per period service or a durable good is private as trade progresses the valuation will be partially revealed and it may be impossible for the parties to commit ex ante not to take advantage of this we analyse this situation first by supposing that the parties can sign a sequence of short term contracts and secondly by supposing that they can sign a long term contract but cannot commit not to renegotiate it later we find a close relationship in the second case between the optimal long term contract and the non commitment outcome in the standard coasian durable good model our results also have implications for hidden information principal agent models

time varying volatilities and calculation of the weighted implied standard deviation rogalski tinic have reported a monthly pattern in ex post stock return variances that differs between small and large market capitalization firms maloney rogalski find that option prices reflect these monthly patterns ex ante this study extends maloney rogalski s work by devising an expiration specific weighted implied standard deviation wisd it is found that i the monthly patterns in one month wisds are basically similar to the monthly patterns in ex post variances detected by rogalski tinic for both large and small size firms and ii use of expiration specific wisds as opposed to standard composite wisds results in improved performance of option pricing models

optimal dynamic procurement policies for a storable commodity with levy prices and convex holding costs abstract in this paper we study a continuous time stochastic inventory model for a commodity traded in the spot market and whose supply purchase is affected by price and demand uncertainty a firm aims at meeting a random demand of the commodity at a random time by maximizing total expected profits we model the firm s optimal procurement problem as a singular stochastic control problem in which controls are nondecreasing processes and represent the cumulative investment made by the firm in the spot market a so called stochastic monotone follower problem we assume a general exponential levy process for the commodity s spot price rather than the commonly used geometric brownian motion and general convex holding costs we obtain necessary and sufficient first order conditions for optimality and we provide the optimal procurement policy in terms of a base inventory process that is a minimal time dependent desirable inventory level that the firm s manager must reach at any time in particular in the case of linear holding costs and exponentially distributed demand we are also able to obtain the explicit analytic form of the optimal policy and a probabilistic representation of the optimal revenue the paper is completed by some computer drawings of the optimal inventory when spot prices are given by a geometric brownian motion and by an exponential jump diffusion process in the first case we also make a numerical comparison between the value function and the revenue associated to the classical static newsvendor strategy

product diversion to a direct competitor a manufacturer will often limit competition among downstream partners by authorizing only a select group of retailers to carry its product however it is not uncommon for authorized retailers to create an additional competitor by diverting units to an unauthorized seller this paper presents an analytical model that demonstrates how diversion from authorized retailers to an unauthorized direct competitor can occur under circumstances not considered by the prior literature in fact diversion can represent a prisoner s dilemma whereby retailers diminish their own profit by selling to the unauthorized direct seller the authorized retailer s profit loss actually increases as the per unit diversion costs incurred by the authorized retailer decrease the model also shows that the unauthorized direct seller earns greater profit by strategically procuring a unilaterally constraining quantity even though this procurement strategy results in an equivalent increase in the quantity sold by the retailers combined the results identify a new reason for diversion and its consequences for retailers and the unauthorized direct seller

stock price volatility mean reverting diffusion and noise abstract using weekly call option prices on twenty five stocks over a ten year period 1975 1985 and calls on the s p 500 stock index futures we find that ex ante market volatility follows a mixed mean reverting diffusion with noise process changes in volatility are correlated across stocks and a marketwide volatility effect is found strong forces pull the volatility back to its long term value the findings suggest the development of new option pricing models

vertical contracts in a supply chain and the bullwhip effect this paper shows that decentralized supply chains in which upstream firms use linear wholesale prices may experience lower upstream production and downstream sales volatility than vertically inte

errors in implied volatility estimation estimating implied volatility by inverting the black scholes formula is subject to considerable error when option characteristics are observed with plausible errors especially for options away from the money large changes in volatility produce small changes in option prices conversely small errors in option prices and other option characteristics produce large errors in implied volatilities in the presence of small measurement errors unobserved truncation of option prices that violate lower bounds for absence of arbitrage can also lead to systematic volatility smiles the paper proposes feasible gls estimators that reduce the noise and bias in implied volatility estimates

strategic inventories in vertical contracts classical reasons for carrying inventory include fixed nonlinear production or procurement costs lead times nonstationary or uncertain supply demand and capacity constraints the last decade has seen active research in supply chain coordination focusing on the role of incentive contracts to achieve first best levels of inventory an extensive literature in industrial organization that studies incentives for vertical controls largely ignores the effect of inventories does the ability to carry inventory influence the problem of vertical control conversely can inventories arise purely due to incentive effects this paper explicitly considers both incentives and inventories and their interplay in a dynamic model of an upstream firm supplier and a downstream firm buyer who can carry inventories in our model none of the classical reasons for carrying inventory exists however as we prove the buyer s optimal strategy in equilibrium is to carry inventories and the supplier is unable to prevent

the efficiency of the finnish market for right issues abstract this paper analyzes the efficiency of the finnish market for right issues the rights traded on the helsinki stock exchange hse are similar instruments to warrants with some special features attached to them the paper first derives appropriate arbitrage conditions for these rights which must be satisfied in informationally efficient markets and then examines these conditions using both ex post and ex ante test procedures the ex post tests which jointly examine market efficiency and synchroneity of the rights and stock market show a staggering amount of violations against the arbitrage bounds however the ex ante tests reveal that high transaction costs prevent normal investors from benefitting from these violations stockbrokers themselves however seem to be able to earn arbitrage profits in the rights market

the spinoff and merger ex date effects this article shows that some of the wealth gains from financial decisions involving changes in security form occur on predictable ex dates for a sample of 113 spinoffs during 1964 to 90 we document an average excess return of 3 0 percent on ex dates roughly the same magnitude as the average announcement date return we conjecture that the spinoff ex date return arises because the parent and subsidiary stocks attract different investors who prefer to buy the separated shares after the ex date we also document that on average the target shareholders in stock for stock mergers earn an excess return of 1 5 percent on merger ex dates recent years have witnessed a large increase in restructuring programs that include divestitures for example kaplan and weisbach 1992 report that 44 percent of a sample of large acquisitions completed in the 1970s and early 1980s had already been divested by the end of the 1980s most divestitures are accomplished by selling an unwanted subsidiary or division to another company or a group of investors for cash based on a casual survey of transactions reported in the mergers and acquisitions magazine this divestiture form is commonly known as a selloff in many cases however the parent company relinquishes control of a subsidiary by simply distributing the subsidiary shares as a nontaxable stock dividend to current stockholders this latter divestiture form is known as a spinoff and has been gaining

procuring fast delivery sole sourcing with information asymmetry this paper studies a queuing model in which a buyer sources a good or service from a single supplier chosen from a pool of suppliers the buyer seeks to minimize the sum of her procurement and operating costs the latter of which depends on the suppliers lead time the selected supplier can regulate his lead time but faster lead times are costly although the buyer selects the supplier to source from possibly via an auction and dictates the contractual terms the buyers bargaining power is limited by asymmetric information the buyer only has an estimate of the suppliers costs while the suppliers know their costs precisely we identify a procurement mechanism that minimizes the buyers total cost procurement plus operating this mechanism is not simple it is a numerically derived nonlinear menu of contracts therefore we study several simpler mechanisms e g one that charges a late fee and one that specifies a fixed lead time requirement no menus no nonlinear functions we find that simple mechanisms are nearly optimal generally within 1 of optimal because asymmetric information conveys significant protection to the supplier i e the supplier is able to retain most of the benefit of having a lower cost renegotiation is another concern with the optimal mechanism because it does not minimize the supply chains cost the firms can be both better off if they throw away the contract and start over interestingly we find that the potential gain from renegotiation is relatively small with either the optimal or our simple mechanisms we conclude that our simple mechanisms are quite attractive along all relevant dimensions buyers performance supply chain performance simplicity and robustness to renegotiation

tests of an american option pricing model on the foreign currency options market this paper tests the ability of the american option pricing model proposed by parkinson 18 or mason 14 to explain the pricing of the foreign currency options traded on the philadelphia stock exchange from february 28 1983 to march 26 1985 we find that the model underprices out of the money options relative to at the money and in the money options this relative underpricing is driven by an underpricing of out of the money call options of short maturity in addition the degree of relative mispricing for most categories of options is shown to be a decreasing function of the time to maturity of the options longer maturity options appear to trade at similar levels of implied volatility whether they are in at or out of the money most of these biases appear consistent with the fact that the underlying spot currency rate follows a mixed jump diffusion process as described in 17

transactions data tests of efficiency of the chicago board options exchange abstract this paper performs lower boundary condition tests based on rational pricing of call options and an implied standard deviation test based on the bid ask prices of options these efficiency tests attempt to closely approximate conditions in the option markets to avoid the pitfalls indicated by phillips and smith 1980 the tests use transactions data and account for the effects of stock and option bid ask prices simultaneity of stock and option prices depth of market execution lag and transaction costs the small and relatively infrequent profits due to market mispricing disappear in the lower boundary tests when transaction costs are taken into account frequent violations of the tighter boundary conditions in the implied standard deviation test are reported but the estimated profits cannot be unambiguously attributed to option market inefficiency

option pricing and replication with transactions costs transactions costs invalidate the black scholes arbitrage argument for option pricing since continuous revision implies infinite trading discrete revision using black scholes deltas generates errors which are correlated with the market and do not approach zero with more frequent revision when transactions costs are included this paper develops a modified option replicating strategy which depends on the size of transactions costs and the frequency of revision hedging errors are uncorrelated with the market and approach zero with more frequent revision the technique permits calculation of the transactions costs of option replication and provides bounds on option prices

stalking information bayesian inventory management with unobserved lost sales retailers are frequently uncertain about the underlying demand distribution of a new product when taking the empirical bayesian approach of scarf 1959 they simultaneously stock the product over time and learn about the distribution assuming that unmet demand is lost and unobserved this learning must be based on observing sales rather than demand which differs from sales in the event of a stockout using the framework and results of braden and freimer 1991 the cumulative learning about the underlying demand distribution is captured by two parameters a scale parameter that reflects the predicted size of the underlying market and a shape parameter that indicates both the size of the market and the precision with which the underlying distribution is known an important simplification result of scarf 1960 and azoury 1985 which allows the scale parameter to be removed from the optimization is shown to extend to this setting we present examples that reveal two interesting phenomena 1 a retailer may hope that compared to stocking out realized demand will be strictly less than the stock level even though stocking out would signal a stochastically larger demand distribution and 2 it can be optimal to drop a product after a period of successful sales we also present specific conditions under which the following results hold 1 investment in excess stocks to enhance learning will occur in every dynamic problem and 2 a product is never dropped after a period of poor sales the model is extended to multiple independent markets whose distributions depend proportionately on a single unknown parameter we argue that smaller markets should be given better service as an effective means of acquiring information

some results on optimal penal codes in asymmetric bertrand supergames abstract optimal penal codes in asymmetric bertrand supergames exhibit security level punishments for the largest firm if no firm has sufficient capacity to service the market then collusion that is barely sustainable by optimal penal codes entails higher capacity utilization by the largest firm than by the other firms collusion supported by optimal penal codes in models with a large firm facing a competitive fringe can result in the large firm having low capacity utilization and thus providing a price umbrella for the fringe firms which have high capacity utilization journal of economic literature classification numbers c72 c73 l11 l13

dynamic duopoly prices and quantities we study a dynamic model of duopoly in which firms choose both prices and quantities if quantity capacity choices are relatively inflexible firms generally carry excess idle capacity in equilibrium because of this enforcement cost firms are unable to achieve monopoly levels this contrasts with models in which which firms compete in either prices or quantities alone on the other hand if capacities are flexible firms may be able to sustain monopoly behaviour

dynamic supplier contracts under asymmetric inventory information in this paper we examine a supply chain in which a single supplier sells to a downstream retailer we consider a multiperiod model with the following sequence of events in period t the supplier offers a contract to the retailer and the retailer makes her purchasing decision in anticipation of the random demand the demand then unravels and the retailer carries over any excess inventory to the next period unmet demand is lost in period t 1 the supplier designs a new contract based on his belief of the retailer s inventory and the game is played dynamically we assume that short term contracts are used i e the contracting is dynamically conducted at the beginning of each period we also assume that the retailer s inventory before ordering is not observed by the supplier this setting describes scenarios in which the downstream retailer does not share inventory sales information with the supplier for instance it captures the phenomenon of retailers distorting past sales information to secure better contracting terms from their suppliers we cast our problem as a dynamic adverse selection problem and show that given relatively high production and holding costs the optimal contract can take the form of a batch order contract which minimizes the retailer s information advantage we then analyze the performance of this type of contract with respect to some useful benchmarks and quantify the value of prudent contract design and the value of inventory information to the supply chain markovian adverse selection models in which the state and action in a period affect the state in the subsequent period are recognized as theoretically challenging and are relatively less understood we take a nontrivial step towards a better understanding of such models under short term contracting

on the valuation of american call options on stocks with known dividends both the roll and the geske equations for the valuation of the american call option on a stock with known dividends are incorrectly specified this note presents the corrected valuation formula explains the misspecifications and provides a numerical example

cournot and bertrand edgeworth competition when rivals costs are unknown abstract we study a two stage game with capacity precommitment followed by price competition where firms have incomplete information about their rival s marginal cost the game has a cournot outcome if and only if the lowest possible marginal cost is sufficiently high relative to the expected marginal cost

estimation bias induced by discrete security prices commonly equilibrium security prices are modeled by continuous state stochastic processes while observed prices are rounded into discrete units this paper models the rounding mechanism and examines the probabilistic structure of the resultant rounded process we provide accurate and simple estimates of the inflation in estimated variance and kurtosis induced by ignoring rounding in particular the maximum likelihood estimate of security price volatility using rounded prices is developed and a simulation analysis is performed to examine the small sample properties of this estimator for many practical applications a simple correction for rounding becomes available

put call parity and market frictions abstract we extend the fundamental theorem of finance and the pricing rule representation theorem to the case in which market frictions are taken into account but the put call parity is still assumed to hold in turn we obtain a representation of the pricing rule as a discounted expectation with respect to a nonadditive risk neutral probability

dynamic business share allocation in a supply chain with competing suppliers this paper studies a repeated game between a manufacturer and two competing suppliers with imperfect monitoring we present a principal agent model for managing long term supplier relationships using a unique form of measurement and incentive scheme we measure a supplier s overall performance with a rating equivalent to its continuation utility the expected total discounted utility of its future payoffs and incentivize supplier effort with larger allocations of future business we obtain the vector of the two suppliers ratings as the state of a markov decision process and we solve an infinite horizon contracting problem in which the manufacturer allocates business volume between the two suppliers and updates their ratings dynamically based on their current ratings and the current performance outcome our contributions are both theoretical and managerial we propose a repeated principal agent model with a novel incentive scheme to tackle a common but challenging incentive problem in a multiperiod s

option pricing and implicit volatilities abstract this paper demonstrates that black scholes implied volatilities can be used to value options in many situations where the assumptions of the black scholes model are violated including i alternative stock processes ii stochastic interest rates and iii market frictions given its computational simplicity this procedure provides an attractive alternative to the more complex models with a direct estimation procedure

some new filter rule tests methods and results mechanical trading rules seem to have more potential than previous tests found fama and blume 1966 looking at the dow 30 of the late 1950s found no profits for the best vipercent rule after adjusting for transactions costs fifteen of these stocks looked profitable in their sample however for the same rule the surviving fourteen show statistically significant profits for 1970 1982 for transactions costs obtainable by floor traders the test used here assumes constant risk premia or more generally that risk premia are on average approximately the same on days in as for the total period

a bayesian approach to modeling stock return volatility for option valuation new measures of stock return volatility are developed to increase the precision of stock option price estimates with bayesian statistical methods volatility estimates for a given stock are developed using prior information on the cross sectional patterns in return volatil ities for groups of stocks sorted on size financial leverage and trading volume call option values computed with the bayesian procedure generally improve prediction accuracy for market prices of call options relative to those computed using implied volatility standard historical volatility or even the actual ex post volatility that occurred during each option s life although the bayesian methods produce biased call price estimators they do reduce the systematic tendency of standard pricing approaches to overprice underprice options on high low volatility stocks little bias improvement is observed with respect to the time to maturity and moneyness of the call options

valuation of american call options on dividend paying stocks empirical tests abstract this paper examines the pricing performance of the valuation equation for american call options on stocks with known dividends and compares it with two suggested approximation methods the approximation obtained by substituting the stock price net of the present value of the escrowed dividends into the black scholes model is shown to induce spurious correlation between prediction error and 1 the standard deviation of stock return 2 the degree to which the option is in the money or out of the money 3 the probability of early exercise 4 the time to expiration of the option and 5 the dividend yield of the stock a new method of examining option market efficiency is developed and tested

the systematic risk of discretely rebalanced option hedges this paper demonstrates that black scholes option pricing model hedge positions that are risk free when rebalanced continuously will frequently exhibit substantial systematic risk when rebalanced at finite intervals this systematic risk may have biased important empir ical tests of the option pricing model moreover this systematic risk means that the blackscholes option pricing model is inherently inconsistent with the discrete time version of the capital asset pricing model capm

resource allocation under demand uncertainty and private information we study the effect of multilateral private information on the efficiency of markets where capacity constrained upstream agents supply a resource to downstream entities facing uncertain end demands we analyze two models a pooling system in which a single downstream principal pools a resource from multiple upstream agents and a distribution system in which one upstream principal allocates a resource across multiple downstream agents we show that the presence of multilateral private information does not hinder efficiency in the pooling system in contrast in the distribution system the quantities allocated to downstream agents can exceed as well as fall short of their first best levels these results shed light on the recently improved performance of u s agricultural produce market and the observed episodes of shortages oversupplies in flu vaccine and other seasonal markets this paper was accepted by manel baucells decision analysis