sequential formation of coalitions in games with externalities and fixed payoff division this paper analyzes a sequential game of coalition formation when the division of the coalitional surplus is fixed and the payoffs are defined relative to the whole coalition structure gains from cooperation are represented by a valuation which maps coalition structures into payoff vectors i show that any core stable coalition structure can be attained as a stationary perfect equilibrium of the game if stationary perfect equilibria may fail to exist in general games a simple condition is provided under which they exist in symmetric games furthermore symmetric stationary perfect equilibria of symmetric games generate a coalition structure which is generically unique up to a permutation of the players a general method for the characterization of equilibria in symmetric games is proposed and applied to the formation of cartels in oligopolies and coalitions in symmetric majority games journal of economic literatureclassification numbers c78 c71 1996 academic press inc

a market to implement the core abstract i present a mechanism whose subgame perfect equilibrium outcomes coincide with the core of an underlying convex tu game the mechanism resembles an asset market in which one of the players is randomly selected as a broker who centralizes trade in addition the rules of the mechanism are independent of the coalitional function therefore the mechanism is useful for an incompletely informed designer who wishes to implement the core of these games the mechanism is inspired by the reduced games relevant for the consistency of the core journal of economic literature classification numbers c71 and c72

preferential trading arrangements as strategic positioning abstract we analyze a three country model of trade negotiations in which countries can form bilateral free trade areas bilateral customs unions or a trilateral preferential trading arrangement and can continue negotiating after reaching an agreement in contrast to the literature on multilateral bargaining the set of agreements can form a nonpartitional network while in contrast to the network literature players can reach multilateral agreements patient enough countries only reach bilateral agreements if insiders gain more than outsiders which allows them to manipulate the status quo in subsequent negotiations however a hub and spoke pattern may then emerge and insiders then dissipate the advantages of strategic positioning we also use variants on the model to explain why a us commitment not to bargain bilaterally sustained progress at gatt negotiations and the rarity of open access preferential trading arrangements

the hotel yield management with two types of room prices overbooking and cancellations abstract we consider a problem for hotel room allocations with early discount cancellations and overbooking in our model customers can book a room in discounted price if they reserve before a certain deadline the model takes overbooking into account we have expressed the expected total sale function proved it is unimodal on the number of allocated rooms for early discount and for overbooking respectively under a condition and clarified the range where the optimal solution exists we have derived an optimal allocation for early discount in a specified model without cancellations and overbooking

dynamic group formation in the repeated prisonerʼs dilemma abstract we consider dynamic group formation in repeated n person prisoner s dilemma agreements in coalitional bargaining are self binding in that they are supported as subgame perfect equilibria of repeated games individuals are allowed to renegotiate the cooperating group agreement through a process of voluntary participation we prove that a cooperating group forms as an absorbing state of a markov perfect equilibrium after a finite number of renegotiations if and only if the group is pareto efficient provided that individuals are patient the cooperating group can only expand

games of fair division abstract we consider the problem of fairly allocating an indivisible good to one of several agents equally entitled to it when monetary compensations to the others are possible our primary normative concept is no envy first we show that there is no non manipulable selection from the no envy solution then we study the direct revelation games associated with subsolutions of the no envy solution the set of equilibrium allocations of any one of them coincides with the set of envy free allocations for the true preferences journal of economic literature classification numbers c72 d63 d7l d82

disagreement in bargaining an empirical analysis of opec abstract we consider a stylised model in which two cartel members bargain over the aggregate production quota in a world of asymmetric information we show that when the two cartel members are sufficiently different the probability of agreement depends on both the current state of demand and initial production specifically the probability of agreement is much lower when demand is low and initial production is relatively high than when demand is high and initial production is relatively low we also find that regardless of the current demand state the more extreme is initial production the higher is the probability of agreement using an event study where we take as events opec production quota announcements we demonstrate empirically that the predictions of the model are borne out

endogenous structures of association in oligopolies the formulation of associations of firms in an oligopoly with linear demand is analyzed as a two stage noncooperative game in the first stage firms form associations in order to decrease their costs and in the second stage they compete on the market examples of associations include r d joint ventures and groups of firms adopting common standards in equilibrium the associations formed exhibit two general features they are asymmetric and inefficient

dynamic processes of social and economic interactions on the persistence of inefficiencies an economy with a finite number of agents and a finite number of states is considered an exogenous institutional rule prescribes which moves from one state to another are feasible to each coalition at each time an agent is called to act with some exogenous probability and he chooses a coalition a feasible new state to move the economy to and side payments between the agents in the coalition the setup can be applied to various dynamic processes of social and economic interactions such as legislative bargaining coalition formation or exchange economies whenever agents are unable to write long term contracts but are otherwise unconstrained both in their ability to write arbitrary spot contracts and in their ability to collude there can be long run inefficiencies with cycles or inefficient steady states however when agents are sufficiently patient the initial state from which the process starts plays no role in the long run moreover when there exists an efficient state that is free of negat

bargaining foundations of shapley value1 a transferable utility economy in which each agent holds a resource which can be used in combination with the resources of other agents to generate value according to the characteristic function v is studied using a dynamic model of bargaining the main theorem establishes that the payoffs associated with efficient equilibria converge to the agents shapley values as the time between periods of the dynamic game goes to zero in addition it is demonstrated that an efficient equilibrium exists and is unique when an additivity condition is satisfied to demonstrate the sensitivity of the solution to the institutional detail we modify the model to allow for partnerships and show that the shapley value is no longer achieved

a theory of endogenous coalition structures consider an environment with widespread externalities and suppose that bind ing agreements can be written we study coalition formation in such a setting our analysis proceeds by defining on a partition function an extensive form bargaining game we establish the existence of a stationary subgame perfect equilibrium for such a game our main results are concerned with the characterization of equilib rium coalition structures we develop an algorithm that generates under certain conditions an equilibrium coalition structure our characterization results are especially sharp for symmetric partition functions in particular we provide a uniqueness theorem and apply our results to a cournot oligopoly journal of economic literature classification numbers c71 c72 c78 d62 q 1999 academic press

marginal contributions and externalities in the value our concern is the extension of the theory of the shapley value to problems involving externalities using the standard axiom systems behind the shapley value for an arbitrary exogenous coalition structure leads to the identification of bounds on players payos around an externality free value in endogenizing the coalition structure we analyze a two stage process of coalition formation in whose second stage our axiomatic results are applied we find reasons to explain inecient coalition structures and provide sucient conditions for eciency

bargaining and value we present and analyze a model of noncooperative bargaining among n participants applied to situations describable as games in coalitional form this leads to a unified solution theory for such games that has as special cases the shapley value in the transferable utility tu case the nash bargaining solution in the pure bargaining case and the recently introduced maschler owen consistent value in the general nontransferable utility ntu case moreover we show that any variation in a certain class of our bargaining procedure which generates the shapley value in the tu setup must yield the consistent value in the general ntu setup

farsighted coalitional stability abstract i define the largest consistent set a solution concept which applies to situations in which coalitions freely form but cannot make binding contracts act publicly and are fully farsighted in that a coalition considers the possibility that once it acts another coalition might react a third coalition might in turn react and so on without limit i establish weak nonemptiness conditions and apply it to strategic and coalitional form games and majority rule voting i argue that it improves on the von neumann morgenstern stable set as it is usually defined but is consistent with a generalization of the stable set as in the theory of social situations journal of economic literature classification numbers c70 c71

forming coalitions and the shapley ntu value a simple protocol for coalition formation is presented first an order of the players is randomly chosen then a coalition grows by sequentially incorporating new members in this order the protocol is studied in the context of non transferable utility ntu games in characteristic function form if weighted utility transfers are feasible when everybody cooperates then the expected subgame perfect equilibrium payoff allocation anticipated before any implemented game is the shapley ntu value

bargaining in standing committees with an endogenous default committee voting has mostly been investigated from the perspective of the standard baron ferejohn model of bargaining over the division of a pie in which bargaining ends as soon as the committee reaches an agreement in standing committees however existing agreements can be amended this article studies an extension of the baron ferejohn framework to a model with an evolving default that reflects this important feature of policymaking in standing committees in each of an infinite number of periods the ongoing default can be amended to a new policy which is in turn the default for the next period the model provides a number of quite different predictions i from a positive perspective the key distinction turns on whether the quota is less than unanimity in that case patient enough players waste substantial shares of the pie each period and the size principle fails in some pure strategy markov perfect equilibria in contrast the unique markov perfect equilibrium payoffs in a unanimity committee coincide with those in the corresponding baron ferejohn framework ii if players have heterogeneous discount factors then a large class of subgame perfect equilibria including all markov perfect equilibria are inefficient

capacity management in rental businesses with two customer bases we consider the allocation of capacity in a system in which rental equipment is accessed by two classes of customers we formulate the problem as a continuous time analogue of the one shot allocation problems found in the more traditional literature on revenue management and we analyze a queueing control model that approximates its dynamics our investigation yields three sets of results first we use dynamic programming to characterize properties of optimal capacity allocation policies we identify conditions under which complete sharing in which both classes of customers have unlimited access to the rental fleet is optimal next we develop a computationally efficient aggregate threshold heuristic that is based on a fluid approximation of the original stochastic model we obtain closed form expressions for the heuristic s control parameters and show that the heuristic performs well in numerical experiments the closed form expressions also show that in the context of the fluid approximation revenues are concave and increasing in the fleet size finally we consider the effect of the ability to allocate capacity on optimal fleet size we show that the optimal fleet size under allocation policies may be lower the same as or higher than that under complete sharing as capacity costs increase allocation policies allow for larger relative fleet sizes numerical results show that even in cases in which dollar profits under complete sharing may be close to those under allocation policies the capacity reductions enabled by allocation schemes can help to lift profit margins significantly

voluntary export restraints on automobiles evaluating a trade policy the authors evaluate the voluntary export restraint that was initially placed on exports of automobiles from japan in 1981 they evaluate the impact this policy had on u s consumer welfare firm profits and foregone tariff revenue from its initiation through 1990

alternating bid bargaining with a smallest money unit abstract in a seminal paper ariel rubinstein has shown that impatience implies determinateness of the two person bargaining problem in this note we show that this result depends also on the assumption that the set of alternatives is a continuum if the pie can be divided only in finitely many different ways for example because the pie is an amount of money and there is a smallest money unit any partition can be obtained as the result of a subgame perfect equilibrium if the time interval between successive offers is sufficiently small we also show that for a fixed discount rate all subgame perfect equilibrium payoffs of the discrete game converge to the solution obtained by rubinstein if the smallest money unit tends to zero

bidding for the surplus a non cooperative approach to the shapley value abstract we propose a simple mechanism to determine how the surplus generated by cooperation is to be shared in zero monotonic environments with transferable utility the mechanism consists of a bidding stage followed by a proposal stage we show that the subgame perfect equilibrium outcomes of this mechanism coincide with the vector of the shapley value payoffs we extend our results to implement the weighted shapley values finally we generalize our mechanism to handle arbitrary transferable utility environments the modified mechanism generates an efficient coalition structure and implements the shapley values of the super additive cover of the environment journal of economic literature classification numbers c71 c72

choosing wisely a multibidding approach reaching decisions about the location of noxious facilities such as dump sites environmentally hazardous plants nuclear power generators and the like is a highly contentious issue for instance in february 2000 the u s senate decided that nationwide nuclear waste would be shipped to the yucca mountain site in nevada conditional to it being approved as a high level nuclear waste repository despite the attractive compensation package the state of nevada voiced vehement opposition president clinton vetoed the bill and in may 2000 the senate failed to overturn it as such the major problem facing the u s nuclear industry on where to site a high level radioactive waste repository remains virtually unresolved neither are decisions about the location of desirable events easily solvable every two years the international olympic committee selects hosts for the summer and winter games a procedure that is constantly under review and revision in order to bring about the best possible outcome until about a year ago the decision was made by a vote based on bids and plans submitted by candidate cities however the recent controversy surrounding the choice of salt lake city to host the 2002 winter games culminated in the design of a new procedure for choosing the host of the 2006 winter games this procedure called for the selection of two finalist cities in this case turin and sion immediately after which the host was selected by secret ballot in this case turin another similar issue is currently the subject of heated debate in spain the spanish government both on the national and local level has recently been discussing various possible projects for transferring water from rivers in the north of spain to the arid southern regions the parties involved have conflicting interests with regard to several aspects of the projects proposed particularly the water rich regions are hesitant to give up parts of their water resources the parties involved have still not agreed upon the choice of a transport mode or the size of the transfer payments that would compensate the localities that are relinquishing part of the water supply these and several other cases belong to a class of problems in which a group of agents has to choose one out of several projects a project is efficient if it maximizes the aggregate welfare of the group members reaching an efficient outcome is trivial when the designer has all the relevant information however it is often the case that the parties concerned possess much more information than the designer hence the designer faces a nontrivial problem if she wishes to optimally choose one of the projects moreover from a normative point of view even if the designer has all the information it is easier to justify the use of a fixed procedure to reach a decision than to modify the procedure for various cases in light of information disclosed or already available to the designer several well known methods are available for the problem of choosing one out of a set of alternatives one class of methods consists of various voting schemes such as majority voting or the borda rule the outcomes generated by these methods need not be efficient due to strategic behavior on the part of the agents another class of methods consists of vickreyclarke groves mechanisms for this class truthtelling is a dominant strategy that always results in the choice of an efficient alternative however these mechanisms are not budgetbalanced and the payments collected from the perez castrillo department of economics code universitat autonoma de barcelona 08193 bellatera barcelona spain wettstein department of economics bengurion university of the negev monaster center for economic research beer sheva 84105 israel we thank herve moulin for his helpful suggestions suresh mutuswami who encouraged us to check for strong nash equilibria and francis bloch mark gradstein moshe justman jordi masso and two anonymous referees for their useful comments perez castrillo gratefully acknowledges financial support from bec2000 0172 and 2000sgr 00054

equilibrium binding agreements abstract we study equilibrium binding agreements the coalition structures that form under such agreements and the efficiency of the outcomes that result we analyze such agreements in a context where the payoff to each player depends on the actions of all other players thus a game in strategic form is a natural starting point unlike the device of a characteristic function explicit attention is paid to the behavior of the complementary set of players when a coalition blocks a proposed agreement a solution concept and its applications are discussed journal of economic literature classification numbers c70 c71

consumption externalities and diffusion in pharmaceutical markets antiulcer drugs we examine the role of consumption externalities in the demand for pharmaceuticals at both the brand level and over a therapeutic class of drugs externalities emerge when use of a drug by others affects its value and or conveys information about efficacy and safety to patients and physicians this can affect the rate of market diffusion for a new entrant and can lead to dominance of one drug despite the availability of close substitutes we use data for h2 antagonist antiulcer drugs to estimate a dynamic demand model and quantify these effects the model has three components an hedonic price equation that measures how the aggregate usage of a drug as well as conventional attributes affect brand valuation equations relating equilibrium market shares to quality adjusted prices and marketing levels and diffusion equations describing the dynamic adjustment process we find that consumption externalities influence both valuations and rates of diffusion and that they operate at the brand and not the therapeutic class level

voting blocs party discipline and party formation abstract i study the strategic incentives to coordinate votes in an assembly coalitions form voting blocs acting as single players and affecting the policy outcome in an assembly with two exogenous parties i show how the incentives to accept party discipline depend on the types of the agents the sizes of the parties and the rules the blocs use to aggregate preferences in a game of fully endogenous party formation i find sufficient conditions for the existence of equilibria with one bloc two blocs and multiple blocs

a new bargaining set of an n person game and endogenous coalition formation abstract the two most fundamental questions in cooperative game theory are when a game is played what coalitions will be formed and what payoff vectors will be chosen few solution concepts or theories in the current literature provide satisfactory answers to both questions answers are especially lacking for the first one in this paper we introduce a new bargaining set which is the first solution concept in cooperative game theory that provides answers to both fundamental questions endogenously journal of economic literature classification number c71

a simple noncooperative core story abstract what are the strategic properties of the core we address this question by considering mechanisms that emulate the no recontracting out property of the core in particular mechanisms are defined relative to a status quo outcome that serves as a disagreement point if no coalition forms to recontract out we then ask the question what is a plausible class of such mechanisms for which the following result is valid a core outcome is a status quo equilibrium outcome of every mechanism in this class a noncore outcome is a status quo equilibrium outcome of no mechanism in this class a class of mechanisms satisfying is said to strategically separate core from noncore outcomes this paper finds one such class a noncooperative core story having the property that agents can explicitly communicate their preferences for association journal of economic literature classification numbers 030 022 025 026

feasible and continuous implementation there has been a great deal of research in recent years investigating the question of whether or not there exist institutions game forms for which the set of equilibria will coincide with the set of walrasian equilibria in this paper we show the existence of a game form that is feasible both for equilibrium and disequilibrium strategies continuous and for which the set of nash equilibria coincides with the set of constrained walrasian equilibria for all pure exchange economies the game form allows agents to behave strategically both with respect to their preferences and their initial endowments

a consistent bargaining set abstract both the core and the bargaining set fail to satisfy a natural requirement of consistency in excluding imputations to which there exist objections the core does not assess the credibility of such objections the bargaining set goes a step further only objections which have no counterobjections are considered justified however the credibility of counterobjections is not similarly assessed we formulate a notion of a consistent bargaining set in which each objection in a chain of objections is tested in precisely the same way as its predecessor various properties of the consistent bargaining set are also analyzed

implementation of bargaining sets via simple mechanisms abstract we propose two simple mechanisms that implement two bargaining sets in super additive environments the first bargaining set is a close variation of the one proposed by l zhou 1994 games econom behav 6 512 526 and the second is the pareto optimum payoffs of the a mas colell 1989 j math econom 18 129 139 bargaining set we adopt a simple framework in which the cooperative outcomes are realized as non cooperative subgame perfect equilibria in pure strategies of a two stage game played by an auxiliary set of individuals competing over the cooperative agents journal of economic literature classification numbers c71 c72

realizing fair outcomes in minimum cost spanning tree problems through non cooperative mechanisms abstract in the context of minimum cost spanning tree problems we present a bargaining mechanism for connecting all agents to the source and dividing the cost among them the basic idea is very simple we ask each agent the part of the cost he is willing to pay for an arc to be constructed we prove that there exists a unique payoff allocation associated with the subgame perfect nash equilibria of this bargaining mechanism moreover this payoff allocation coincides with the rule defined in bergantinos and vidal puga bergantinos g vidal puga j j 2007a a fair rule in minimum cost spanning tree problems journal of economic theory 137 326 352

sharing a river among satiable agents abstract we consider the problem of efficiently sharing water from a river among a group of satiable agents since each agent s benefit function exhibits a satiation point the environment can be described as a cooperative game with externalities we show that the downstream incremental distribution is the unique distribution which both is fair according to the aspiration welfare principle and satisfies the non cooperative core lower bounds on the other hand the cooperative core may be empty furthermore the downstream incremental distribution satisfies all core lower bounds for all connected coalitions if and only if each agent s individual rationality constraint is independent of the behavior of the other agents

regulation and pricing of pharmaceuticals reference pricing or price cap regulation we study the relationship between regulatory regimes and pharmaceutical firms pricing strategies using a unique policy experiment from norway which in 2003 introduced a reference price rp system called index pricing for a sub sample of off patent pharmaceuticals replacing the existing price cap pc regulation we estimate the effect of the reform using a product level panel dataset covering the drugs exposed to rp and a large number of drugs still under pc regulation in the time before and after the policy change our results show that rp significantly reduced both brand name and generic prices within the reference group with the effect being stronger for brand names we also identify a negative cross price effect on therapeutic substitutes not included in the rp system in terms of policy implications the results suggest that rp is more effective than pc regulation in lowering drug prices while the cross price effect raises a concern about patent protection

reinterpreting the kernel the reduced game relevant for the consistency of the prekernel is used to reinterpret this solution concept in a way that makes it independent of interpersonal utility comparisons based on this reinterpretation a non cooperative model is presented that yields in stationary equilibria the prekernel kernel for the class of monotonic transferable utility games next we apply the same non cooperative model to more general coalitional games for pure bargaining problems the model yields the nash solution for general non transferable utility games a natural extension of the prekernel arises thus the prekernel is obtained as the set of payoffs where the relevant bargaining range between every pair of players is split in half journal of economic literatureclassification numbers c71 c72 c78

conflict and distribution abstract we develop a behavioral model that links the level and pattern of social conflict to the societywide distribution of individual characteristics the model can be applied to groups that differ in characteristics such as wealth ethnicity religion and political ideology we settle questions of existence and uniqueness of conflict equilibrium conflict is seen to be closely connected with the bimodality of the underlying distribution of characteristics however in general the conflict distribution relationship is nonlinear and surprisingly complex our results on conflict patterns also throw light on the phenomena of extremism and moderation journal of economic literature classification numbers d63 d72 d74

contracting with externalities and outside options this paper proposes a model of multilateral contracting where players are engaged in two parallel interactions they dynamically form coalitions and play a repeated normal form game with temporary and permanent decisions we show that when outside options are independent of the actions of other players all markov perfect equilibrium without coordination failures are efficient regardless of externalities created by interim actions otherwise in the presence of externalities on outside options all markov perfect equilibrium may be inefficient this formulation encompasses many economic models and we analyze the distribution of coalitional gains and the dynamics of coalition formation in four illustrative applications

coalition formation as a dynamic process abstract we study coalition formation as an ongoing dynamic process with payoffs generated as coalitions form disintegrate or regroup a process of coalition formation pcf is an equilibrium if a coalitional move to some other state can be justified by the expectation of higher future value compared to inaction this future value in turn is endogenous it depends on coalitional movements at each node we study existence of equilibrium pcfs we connect deterministic equilibrium pcfs with unique absorbing state to the core and equilibrium pcfs with multiple absorbing states to the largest consistent set in addition we study cyclical as well as stochastic equilibrium pcfs

a three player dynamic majoritarian bargaining game this file contains two sets of calculations first we report the calculations of demands and continuation values of proposition 1 second the mixing probabilities of proposition 1 are shown to be well defined

bargaining and bargaining sets abstract we argue that in exchange economies various versions of the bargaining set cannot be implemented in nash equilibrium we then propose an extensive form mechanism that exactly implements the aumann davis maschler bargaining set in subgame perfect equilibrium the mechanism corresponds closely to the description of the bargaining set and respects feasibility in and out of equilibrium journal of economic literature classification numbers c71 c72 c78 d51

identifying industry margins with price constraints structural estimation on pharmaceuticals we develop a structural model to investigate the effects of pharmaceutical price regulation on demand and on manufacturers price setting behavior in france we estimate price cost margins in a regulated market with price constraints and infer whether these constraints are binding exploiting cost restrictions across drugs which come from observing the same drugs in potentially price constrained markets france and in markets where prices are unregulated us and germany our counterfactual simulations suggest that price constraints generated modest savings for anti ulcer drugs in 2003 2013 2 percent of total expenses relative to a free pricing scenario and shifted consumption from generic to branded drugs

bidding for surplus in network allocation problems in this paper we study non cooperative foundations of network allocation rules we focus on three allocation rules the myerson value the position value and the component wise egalitarian solution for any of these three rules we provide a characterization based on component efficiency and some balanced contribution property additionally we present three mechanisms whose equilibrium payoffs are well defined and coincide with the three rules under consideration if the underlying value function is monotonic non monotonic value functions are shown to deal with allocation rules applied to monotonic covers the mechanisms are inspired by the implementation of the shapley value by perez castrillo and wettstein bidding for the surplus a non cooperative approach to the shapley value j econ theory 100 2 2001 274 294

subgame perfect implementation this paper examines the use of stage mechanisms in implementation problems and provides a partial characterization of the set of subgam e perfect implementable choice rules it is shown that in many economic environments virtually an y choice rule can be implemented to illustrate the power of this approach the paper discusses a number of models in which it is possible to implement the first best although it wouldn t have been possible to do so without using stage mechanisms the diversity of these models suggests that subgame perfect implementation may find wide application copyright 1988 by the econometric society

rational bargaining in games with coalitional externalities this paper provides a flexible strategic framework to analyze bargaining and values in environments with coalitional externalities within this framework we propose a new value that extends the shapley value to partition function form games the so called rational belief shapley rbs value we investigate the strategic foundation of the rbs value by constructing an implementation mechanism this mechanism extends existing models of multilateral bargaining by allowing players a higher degree of freedom to form coalitions the same framework of bidding and renegotiation allows for natural variations of the rbs mechanism in this way alternative shapley like values are obtained and a unified platform to analyze and compare these solutions is provided

an implementation of the owen value abstract we present an implementation of the owen value owen 1977 essays in mathematical economics and game theory pp 76 88 inspired by the bidding mechanism introduced by perez castrillo and wettstein 2001 j econ theory 100 274 294 the idea is the following first players of each coalition play the bidding mechanism trying to obtain the resources of the coalition later players who obtained the resources play the bidding mechanism in order to share the surplus

confining the coase theorem contracting ownership and free riding if individuals own the right to take any action that they please and are free to contract about behaviour will outcomes be efficient in all situations that is does the coase theorem hold we study this classic question through the lens of a non cooperative model of contract negotiations considering both compulsory and voluntary participation in negotiations in either case we find that all consistent equilibria of the contracting game are efficient in the case of two players but if participation is voluntary and there are more than two players there are situations in which all consistent equilibria are inefficient specifically the provision of public goods tends to be inefficiently low due to strategic abstention from contracting free riding on others agreements can be avoided if individuals do not own all their actions when actions involve the use of assets efficient action ownership may correspond to collective rather than individual asset ownership

a note on the theory of the firm under multiple uncertainties abstract we develop a dynamic continuous time theory of the competitive firm under multiple correlated uncertainties output price uncertainty and output uncertainty as an example in doing so we completely generalize and extend the previous one period comparative statics results the marginal impact of each parameter on optimal output particularly we relax the assumption of the statistical independence between the risks and the restrictions on the coefficient of absolute relative risk aversion furthermore we generally show the impact of one risk on the aversion to another moreover we show the role of the factor of correlation between risks on the decisions of the firm

consistent solutions for cooperative games with externalities in order to calculate the worth of a coalition of players the coalition needs to predict the actions of outsiders we propose that for a given solution concept such predictions should be made by applying the solution concept to the reduced society consisting of the non members we illustrate by computing the r core for the case of bertrand competition with differentiated commodities

transparency complementarity and holdout this paper characterizes the conditions under which holdout i e bargaining inefficiency may or may not be significant in a two sided one buyer many seller model with complementarity we address this problem in a very general setup with a bargaining protocol that is symmetric and allows for both publicly observable as well as secret offers and a technology that allows for variable degrees of complementarity the central insight is that the transparency of the bargaining protocol formalized by whether offers are publicly observable or secret as well as the extent of complementarity play a critical role in generating efficiency even with perfect complementarity holdout seems to be largely resolved whenever the bargaining protocol is public but not if it is secret further irrespective of the bargaining protocol holdout is resolved if the marginal contribution of the last seller is not too large

coalition formation with binding agreements we study coalition formation in real time a situation in which coalition formation is intertwined with the ongoing receipt of pay offs agreements are assumed to be permanently binding they can only be altered with the full consent of existing signatories for characteristic function games we prove that equilibrium processes whether or not these are history dependent must converge to efficient absorbing states for three player games with externalities each player has enough veto power that a general efficiency result can be established however there exist four player games in which all markov equilibria are inefficient from every initial condition despite the ability to write permanently binding agreements copyright 2007 wiley blackwell

how organizational resources affect strategic change and performance in turbulent environments theory and evidence this study examines how historical resource endowments and competencies affect strategic change and its outcomes amid environmental turbulence drawing from both behavioral and economics based literatures we develop four distinct perspectives regarding the likely effect of resources on strategic change these four perspectives offer alternative predictions about how and why resource endowments should affect the likelihood or magnitude of strategic change and how and why they should moderate the relation between strategic change and performance we examine the predictive power of these four alternative arguments using extensive longitudinal data from a single industry context characterized both by substantial resource heterogeneity and environmental turbulence results indicate that organizations possessing greater stocks of historically valuable resources were much less likely to engage in adaptive strategic change but also that this resource driven disinclination towards change tended to have a benign or even beneficial effect on performance we discuss the implications of our theory and findings for the strategic change literature and also for the literature on the resource based view of the firm

portfolio optimization under loss aversion abstract we present an integrated methodological approach for selecting portfolios the proposed methodology is focused on incorporation of investor s preferences in the mean risk framework we propose a risk measure calculated with the downside part of the portfolio return distribution which we argue captures better the practical behavior of the loss averse investor we establish its properties study the link with stochastic dominance criteria point out the relations with conditional value at risk and lower partial moment of first order and give the explicit formula for the case of scenario based portfolio optimization the proposed methodology involves two stages firstly the investment opportunity set efficient frontier is determined and secondly one single preferred efficient portfolio is selected namely the one having the highest expected utility value three classes of utility functions with loss aversion corresponding to three types of investors are considered the empirical study is targeted on assessing the differences between the efficient frontier of the proposed model and the classical mean variance mean cvar and mean lpm1 frontiers we firstly analyze the loss of welfare incurred by using another model instead of the proposed one and measure the corresponding gain loss of utility secondly we assess how much the portfolios really differ in terms of their compositions using a dissimilarity index based on the 1 norm we describe and interpret the optimal solutions obtained and emphasize the role and influence of loss aversion parameters values and of constraints three types of constraints are studied no short selling allowed a certain degree of diversification imposed and short selling allowed

a noncooperative theory of coalitional bargaining the authors explore a sequential offers model of n person coalitional bargaining with transferable utility and with time discounting their focus is on the efficiency properties of stationary equilibria of strictly superadditive games when the discount factor delta is sufficiently large it is shown that delay and the formation of inefficient subcoalitions can occur in equilibrium the latter for some or all orders of proposer however efficient stationary equilibrium payoffs converge to a point in the core as delta approaches one strict convexity is a sufficient condition for there to exist an efficient stationary equilibrium payoff vector for sufficiently high delta

a noncooperative view of coalition formation and the core a noncooperative implementation of the core is provided for games with transferable utility the implementation obtained here is meant to reflect the standard motivation for the core as closely as possible in the model proposed time is continuous this idealized treatment of time is most amenable for capturing an essential feature of the core there is always time to reject a noncore proposal before it is consumated

profit management of car rental companies abstract a car rental company consists of a fleet of available rentable vehicles waiting to be rented and being rented we model the company as a family of birth death processes bdps in equilibrium with finite size indexed by the company utilization parameter this metric is the ratio of the primary birth and death rates in these bdps relying on the basic concepts of company information and company entropy i e mean information we promote a procedure for profit management of car rental companies the company entropy represents the company uncertainty i e risk moreover finding optimal values of company utilization and fleet size leads to a unique management of that uncertainty introducing the coefficient of proportionality of a company as ratio of the renting revenue per vehicle per day and costs per vehicle per day we obtain an expression for the mean profit per day of a company i e profit attained per day from the average number of simultaneously rented vehicles as a function of company utilization fleet size and coefficient thus the profit management procedure reduces to finding optimal values of these three metrics as the key profit drivers of the rental business moreover an expression for the minimal value of the coefficient is introduced as a function of the other two metrics determining the zero mean profit per day thereby the efficiency of the company s fleet is determined as a reciprocal of this minimal value the developed procedure is illustrated on a company which is represented by the erlang loss system

the private provision of excludable public goods an inefficiency result abstract does voluntary contracting suffice for the efficient provision of excludable public goods even in a complete information environment we find that the answer is negative the reason is that some agents may profit from not participating at the provision stage but instead negotiate access ex post

a theory of gradual coalition formation we study noncooperative multilateral bargaining games based on underlying tu games in which coalitions can renegotiate their agreements we distinguish between models in which players continue to bargain after implementing agreements reversible actions and models in which players who implement agreements must leave the game irreversible actions we show that renegotiation always results in formation of the grand coalition if actions are reversible but that the process may otherwise end with smaller coalitions on the other hand we show that the grand coalition cannot form in one step if the core of the game is empty irrespective of the reversibility of actions agreements between players form the basis of much that game theory seeks to explain there are obviously many useful ways to categorize such agreements in multilateral negotiations that is with more than two participants it seems natural to distinguish between cases in which the coalition forms in one step and those in which the coalition grows to its eventual size by attracting new members thus recipients of marshall aid collectively agreed to american terms at the ceec in 1947 whereas a strict subset of these countries agreed to the schuman plan in 1950 with the other current members joining the eu over time similarly negotiations on climate change culminated in universal agreement at rio in 1992 whereas india and china only agreed to reduce cfc emissions in london in 1990 after other countries had signed up to the montreal protocol finally un security council resolution 242 urged that a multilateral conference be set up to establish a comprehensive settlement in the middle east whereas the process initiated by the oslo agreements and arguably camp david has consisted of a sequence of agreements between israel and its neighbours we will refer to cases in which the grand coalition forms in one step as involving immediate coalition formation or icf for short and cases in which a coalition grows as involving gradual coalition formation

negotiating free trade we develop a dynamic bargaining model in which a leading country endogenously decides whether to sequentially negotiate free trade agreements with subsets of countries or engage in simultaneous multilateral bargaining with all countries at once we show how the structure of coalition externalities shapes the choice between sequential and multilateral bargaining and we identify circumstances in which the grand coalition is the equilibrium outcome leading to worldwide free trade a model of international trade is then used to illustrate equilibrium outcomes and how they depend on the structure of trade and protection global free trade is not achieved when the political economy motive for protection is sufficiently large furthermore the model generates both building bloc and stumbling bloc effects of preferential trade agreements in particular we describe an equilibrium in which global free trade is attained only when preferential trade agreements are permitted to form a building bloc effect and an equilibrium in which global free trade is attained only when preferential trade agreements are forbidden a stumbling bloc effect the analysis identifies conditions under which each of these outcomes emerges

efficient bidding with externalities we implement a family of efficient proposals to share benefits generated in environments with externalities these proposals extend the shapley value to games with externalities and are parametrized through the method by which the externalities are averaged we construct two slightly different mechanisms one for environments with negative externalities and the other for positive externalities we show that the subgame perfect equilibrium outcomes of these mechanisms coincide with the sharing proposals

efficiency and effectiveness in the urban public transport sector a critical review with directions for future research abstract this paper proposes a self contained reference for both policy makers and scholars who want to address the problem of efficiency and effectiveness of local public transport lpt with special emphasis on urban transit in a sound empirical way framing economic efficiency studies into a transport planning perspective it offers a critical discussion of the existing empirical studies relating them to the main methodological approaches used the connection between such perspectives and operations research studies dealing with scheduling and tactical design of public transport services is also developed the comprehensive classification of selected relevant dimensions of the empirical literature namely inputs outputs kind of data analysed methods adopted and policy relevant questions addressed and the systematic investigation of their interrelationships allows us to summarise the existing literature and to propose desirable developments and extensions for future studies in the field

automobile prices in market equilibrium with unobserved price discrimination in markets where sellers are able to price discriminate or the buyers to bargain individuals receive discounts over the posted prices that are usually not observed by the econometrician this paper considers the structural estimation of a demand and supply model a la berry et al 1995 when only posted prices are observed we consider that heterogeneous discounts occur due to price discrimination by firms on observable characteristics of consumers within this framework identification is achieved by assuming that the marginal costs of producing and selling the goods do not depend on the characteristics of the buyers we also require a condition relating the posted prices to the prices actually paid for instance we can assume that at least one group of individuals pays the posted prices under these two conditions the demand and supply parameters as well as the exact discounts corresponding to each type of consumers can be identified we apply our methodology to estimate the demand and supply in the new automobile market in france results suggest that discounting arising from price discrimination is important the average discount is estimated to be 10 5 with large variation depending on the buyers characteristics and cars specifications our results are in line with discounts generally observed in european and american automobile markets

sharing the surplus an extension of the shapley value for environments with externalities economic activities both on the macro and micro level often entail wide spread externalities this in turn leads to disputes regarding the compensation levels to the various parties affected we propose a method of deciding upon the distribution of the gains costs of cooperation in the presence of externalities when forming the grand coalition is efficient we show that any sharing rule satisfying efficiency linearity dummy player and a strong symmetry axioms can be obtained through an average game adding an additional axiom we identify one unique rule satisfying these properties