efficient resource allocation on the basis of priorities many institutions allocate resources by non market mechanisms based on priorities in this paper we introduce a model of resource allocation on the basis of priorities and address the following questions is it possible to allocate resources on the basis of any priority structure if yes when can we do this pareto efficiently without creating incentives for manipulation and consistently across different groups of agents and resource levels we adopt a basic indivisible objects model with a finite number of object types and a finite quota of goods of each type some interesting examples are the determination of access to education allocation of graduate houses offices or tasks agents are assumed to have strict preferences over object types and remaining unassigned an assignment is an allocation of the objects to the agents such that every agent receives at most one object a rule associates an assignment to each preference profile we formalize a priority structure to be a collection of strict priority rankings of individuals indexed by the object types where i a j would be read as i has higher priority for object a than j we assume that the priority structure is exogenously fixed and allow the preferences of the agents to vary a rule is said to violate a priority of i for a if there is a preference profile under which i envies j who is assigned a and publication information econometrica 70 6 november 2002 2489 2497 the copyright to this article is held by the econometric society http www econometricsociety org it may be downloaded printed and reproduced only for personal or classroom use absolutely no downloading or copying may be done for or on behalf of any for profit commercial firm or other commercial purpose without the explicit permission of the econometric society for this purpose contact julie p gordon executive director of the society at jpg northwestern edu i would like to thank faruk gul wolfgang pesendorfer the co editor the four anonymous referees and the participants of the micro theory lunch seminar in princeton university for their comments and suggestions

bilateral bargaining with externalities this paper provides an analysis of a non cooperative pairwise bargaining game between agents in a network we establish that there exists an equilibrium that generates a coalitional bargaining division of the reduced surplus that arises as a result of externalities between agents that is we provide a non cooperative justification for a cooperative division of a non cooperative surplus the resulting division is related to the myerson shapley value with properties that are particularly useful and tractable in applications we demonstrate this by examining buyer seller networks and vertical foreclosure

the role of firm size in bilateral bargaining a study of the cable television industry we examine the effect of buyer merger on bilateral negotiations between a supplier and n buyers merger may have bargaining effects in addition to the usual efficiency effects the effect of merger on the buyers bargaining position depends on the curvature of the supplier s gross surplus function merger enhances worsens the buyers bargaining position if the function is concave convex based on a panel of advertising revenue in the cable television industry our estimates indicate that the gross surplus function for suppliers of program services is convex this result suggests that cable operators integrate horizontally to realize efficiency gains rather than to enhance their bargaining position vis a vis program suppliers

on two competing mechanisms for priority based allocation problems we consider the priority based allocation problem there is a set of indivisible objects with multiple supplies e g schools with seats and a set of agents e g students with priorities over objects e g proximity of residence area we study two well known and competing mechanisms the agentoptimal stable mechanism aosm allots objects via the deferred acceptance algorithm the top trading cycles mechanism ttcm allots objects via gale s top trading cycles algorithm we show that the two mechanisms are equivalent or ttcm is fair i e respects agents priorities or resource monotonic o rpopulation monotonic if and only if the priority structure is acyclic furthermore if aosm fails to be efficient consistent for a problem ttcm also fails to be fair consistent for it however the converse is not necessarily true

decentralized trading strategic behaviour and the walrasian outcome for a market with a finite number of agents pairwise matching and bargaining it is shown that even when the market is frictionless the equilibrium is not necessarily competitive it depends on the amount of information agents use if their behaviour is conditioned only on the sets of agents present and the time the competitive solution is the unique subgame perfect equilibrium if agents have full information and condition their behaviour on some of it there are also noncompetitive equilibria in which behaviour depends on specific information such as the identity of the trading partner and past events

return autocorrelation and institutional investors abstract we propose and test the hypothesis that trading by institutional investors contributes to serial correlation in daily returns our results demonstrate that nyse particles and individual security daily return autocorrelationsare an increasing function of the level of institutional ownership moreover the results are consistent with the hypothesis that institutional trading reflects information and increases the speed of price adjustment the relation between autocorrelation and institutional holdings does not however apparent to be driven by market frictions or rational time varying required rates of return we conclude that institutional investors correlated trading patterns contribute to axial correlation in daily returns

testing for imperfect competition at the fulton fish market in this article i report the results of a study of the prices paid by individual buyers at the fulton fish market in new york city in principle this is a highly competitive market in which there should be no predictable price differences across customers who are equally costly to service the results indicate that different buyers pay different prices for fish of identical quality for example asian buyers pay 7 less for whiting than do white buyers a result which is inconsistent with the model of perfect competition

matching markets with mixed ownership the case for a real life assignment mechanism we consider a common indivisible good allocation problem whose popular applications include on campus housing kidney exchange and school choice we show that the so called new house 4 nh4 mechanism which has been in use at mit since the 1980s is equivalent to a natural adaptation of the well known gale shapley gs mechanism we run two experiments comparing nh4 with the prominently advocated top trading cycles ttc mechanism and nh4 with gs we find that under nh4 the participation rate is significantly higher than under ttc based on a new ordinal test of efficiency nh4 is more likely to pareto dominate ttc

bargaining in a network of buyers and sellers abstract we analyze bargaining between buyers and sellers who are connected by an exogenously given network players can make repeated alternating public offers that may be accepted by any of the responders linked to each specific proposer our purpose is to find the conditions of the network which drive the price distribution in equilibrium this paper uses graph theory tools to provide necessary and sufficient conditions regarding the architecture of networks for the subgame perfect equilibrium of the bargaining game to coincide with the walrasian outcome

stable trading structures in bilateral oligopolies abstract this paper analyzes the formation of trading groups in a bilateral market where agents trade according to a shapley shubik j polit econ 85 1977 937 968 trading mechanism the only strongly stable trading structure is the grand coalition where all agents trade on the same market other weakly stable trading structures exist and are characterized by an ordering property trading groups can be ranked by size and cannot contain very different numbers of traders of the two types journal of economic literatureclassification numbers d43 d51

matching with couples stability and incentives in large markets accommodating couples has been a longstanding issue in the design of centralized labor market clearinghouses for doctors and psychologists because couples view pairs of jobs as complements a stable matching may not exist when couples are present this paper s main result is that a stable matching exists when there are relatively few couples and preference lists are suciently short relative to market size we also discuss incentives in markets with couples we relate these theoretical results to the job market for psychologists in which stable matchings exist for all years of the data despite the presence of couples

a theory of buyer seller networks this paper introduces a new model of exchange networks rather than markets of buyers and sellers it begins with the empirically motivated premise that a buyer and seller must have a relationship a link to exchange goods networks buyers sellers and the pattern of links connecting them are common exchange environments this paper develops a methodology to study network structures and explains why agents may form networks in a model that captures characteristics of a variety of industries the paper shows that buyers and sellers acting strategically in their own self interests can form the network structures that maximize overall welfare

liquidity risk in stock returns an event study perspective we examine in an event study context what factors affect the relative performance of stocks during liquidity crises we find that market risk measured by the market beta is not a good measure of expected abnormal stock returns on days with liquidity crises instead abnormal stock returns during liquidity crises are strongly negatively related to liquidity risk measured by the co movement of stock returns with market liquidity the degree of informational asymmetry and the ownership structure of the firm also help to explain abnormal stock returns on crisis days our findings have important implications for managing the liquidity risk of equity portfolios

worker substitutability and patterns of unionisation a strategic three party bargaining model is developed in which one distinguished party the firm has to reac h agreements with the other two each of which is a group of workers in the prebargaining stage the two worker groups decide whether to organize jointly or separately the main observation relates the equi librium pattern of unionization to the substitutability in production between the two groups the outcome is joint or separate unions acco rding to whether the two groups are substitute or complementary facto rs of production the analysis also considers possibilities for firm s strategic intervention in the unionization process copyright 1988 by royal economic society

upstream horizontal mergers vertical contracts and bargaining abstract we study horizontal mergers in the upstream sectors of vertically related industries when bargaining is present and contract types are endogenous we demonstrate that the contract types used can have significant implications for the equilibrium market structure and vice versa when trading takes place through two part tariff contracts merger incentives are absent however when the downstream firms are powerful merger incentives are restored since the merger leads then either to the exclusive or to the partial use of wholesale price contracts finally we show that whenever a merger occurs it is welfare detrimental

bilateral oligopoly the efficiency of intermediate goods markets abstract we show that intermediate goods markets may be efficient despite the presence of commonly accepted signs of market failure such as high concentration both among sellers and buyers sparse trading networks price dispersion and externalities the results are derived in an extensive form model of bilateral bargaining with multiple buyers and multiple sellers and with externalities between the negotiations we also characterize the structure of the endogenous trading network i e how firms choose trading partners prices are dispersed and depend on both the concentration of capital and the concentration of sales consistent with some stylized facts on buyer power

strategyproof assignment by hierarchical exchange we give a characterization of the set of group strategyproof pareto optimal and reallocation proof allocation rules for the assignment problem where individuals are assigned at most one indivisible object without any medium of exchange although there are no property rights in the model the rules satisfying the above criteria imitate a trading procedure with individual endowments in which individuals exchange objects from their hierarchically determined endowment sets in an iterative manner in particular these assignment rules generalize gale s top trading cycle procedure the classical rule for the model in which each individual owns an indivisible good

bilateral monopolies and incentives for merger the paper presents a model of duopoly in which firms acquire inputs through bilateral monopoly relations with suppliers it combines a bargaining model with a duopoly model to examine how input pri

chinese college admissions and school choice reforms a theoretical analysis each year approximately 10 million high school seniors in china compete for 6 million seats through a centralized college admissions system within the last decade many provinces have transitioned from a sequential to a parallel mechanism to make their admissions decisions in this study we characterize a parametric family of application rejection assignment mechanisms including the sequential deferred acceptance and parallel mechanisms in a nested framework we show that all of the provinces that have abandoned the sequential mechanism have moved toward less manipulable and more stable mechanisms we also show that existing empirical evidence is consistent with our theoretical predictions

why do popular mechanisms lack efficiency in random environments we consider the problem of randomly assigning n indivisible objects to n agents recent research introduced a promising mechanism the probabilistic serial that has superior e ciency properties than the most common real life mechanism random priority on the other hand mechanisms based on gale s celebrated top trading cycles method have long dominated the indivisible goods literature with the exception of the present context thanks to their outstanding e ciency features we present an equivalence

do liquidity measures measure liquidity abstract given the key role of liquidity in finance research identifying high quality proxies based on daily as opposed to intraday data would permit liquidity to be studied over relatively long timeframes and across many countries using new measures and widely employed measures in the literature we run horseraces of annual and monthly estimates of each measure against liquidity benchmarks our benchmarks are effective spread realized spread and price impact based on both trade and quote taq and rule 605 data we find that the new effective realized spread measures win the majority of horseraces while the amihud 2002 illiquidity and stock returns cross section and time series effects journal of financial markets 5 31 56 measure does well measuring price impact

countervailing power and consumer prices this paper considers the importance of countervailing power manifested as the effects of increased retail concentration on consumer prices and welfare within a market setting where imperfectly competitive retailers negotiate intermediate prices with a monopoly supplier only when retailer services are regarded as very close substitutes do final prices fall following a reduction in the number of retailers even in these circumstances the social benefits of countervailing power may not be realised as the supplier may seek to protect its profits by using a refusal to supply restraint to engage in exclusive trading

buyer power and mutual dependency in a model of negotiations we study bilateral bargaining between several buyers and sellers in a framework that allows both sides in case of a bilateral disagreement flexibility to adjust trade with each of their other trading partners and receive the gross benefit generated by each adjustment a larger buyer pays a higher per unit price when buyers bargaining power in bilateral negotiations is sufficiently low and a lower price otherwise an analogous result holds for sellers these predictions and the implications of different technologies are explained by the fact that size is a source of mutual dependency and not an unequivocal source of power

multiunit bargaining in oligopolistic industries a model of wage determination in unionized oligopolistic industries is developed and used to compare the outcome of collective bargaining under two different bargaining structures one in which the workers of each firm are represented by separate and independent unions local bargaining and one in which a national union represents all workers in the industry in both cases the bargaining problem has a unique outcome with industrywide bargaining resulting in higher wages in addition industrywide unions are inherently stable in that there are no incentives for independent unions to attempt to cheat on the collusive agreement

opportunism in multilateral vertical contracting nondiscrimination exclusivity and uniformity comment an input supplier selling to competing downstream firms would benefit from publicly committing at the outset to all contracts efficient commitment however would require complete contracts the authors study instead bilateral contracting without commitment regarding others terms each firm then fears that the supplier might opportunistically renegotiate another s contract to increase bilateral profit at the firm s expense the authors show that nondiscrimination clauses generally cannot curb such third party opportunism even with symmetric firms to reassure firms crude forms of commitment may be adopted this could explain the pervasiveness of exclusivity arrangements and the striking uniformity and intertemporal rigidity of franchise contracts copyright 1994 by american economic association

on the operation of multiple matching markets abstract we provide a new perspective on how to operate matching markets when there are many types of markets our finding is that the market wise adaptation of strategy proof and non wasteful rules yields a strategy proof rule with the following efficiency property no strategy proof rule pareto dominates the rule such rules are abundant as they include the market wise use of the well known priority based rules of the top trading cycles and the deferred acceptance this result gives theoretical support to the independent operation of markets observed in real life markets as well as our practice in market design that separately treats each market for its design

coalitional strategy proof house allocation abstract we consider house allocation without endowments we show that there is a unique maximal domain including all strict preferences on which efficiency and coalitional strategy proofness are compatible a preference relation belongs to the unique maximal domain if it is a strict descending ranking of houses to a certain house and indifference holds over it and the remaining houses we also show that on this domain mixed dictator pairwise exchange rules are the only rules satisfying efficiency and coalitional strategy proofness journal of economic literature classification numbers c78 d63 d71

on responsiveness of top trading cycles mechanism to priority based affirmative action abstract in school choice priority based affirmative action favors minority students by means of promoting their priority ranking at schools this paper investigates the responsiveness of the top trading cycles mechanism to priority based affirmative action when schools priority structure satisfies a certain acyclicity condition when schools priority under the problem without affirmative action satisfies virtual homogeneity condition a weak responsiveness result is obtained