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

cooperative and noncooperative r d in duopoly with spillovers contrary to the usual assumption made in most oligopoly models relations among firms are seldom of a wholly cooperative or noncooperative type in many situations they compete in some fields while they cooperate in others an important example is the case of cooperative research efforts bringing fierce competitors together two types of agreement are observed first r d cooperation can take place at the so called precompetitive stage companies share basic information and efforts in the r d stage but remain rivals in the market place 1 a second type of agreement involves an extended collusion between partners creating common policies at the product level the usual justifications of this extension are the difficulties of protecting intellectual property the idea is then to allow partners who have achieved inventions together to also control together the processes and products which embody the results of their collaboration in order to recuperate jointly their r d investments 2 what could be expected from these types of agreement is a reduction in r d expenditures because of less wasteful duplication and a reduction of total production because of more reprinted from the american economic review 78 5 1133 1137 1988 center for operations research econometrics 1348 louvain la neuve belgium we are grateful to jean

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

lp modeling for asset liability management a survey of choices and simplifications dynamic linear programming lp models for asset liability management alm are quite powerful and flexible but face two challenges 1 many modeling choices not all consistent with one another or with finance theory and 2 solution difficulties due to the large number of scenarios obtained from standard interest rate models we first survey these modeling choices with a view to help researchers make self consistent choices next we review how the dynamic lp model for alm and the representation of uncertainty therein have been simplified in the past to motivate new or hybrid models emphasizing tractability to this end we review existing static lp models as extreme modeling simplifications and aggregation as a simplification of uncertainty

the effects of hospitals governance on optimal contracts bargaining vs contracting we propose a two stage model to study the impact of different hospitals governance frameworks on the optimal contracts designed by third party payers when patients disease severity is the private information of the hospital in the second stage doctors and managers interact within either a bargaining or a contracting scenario in the contracting scenario managers offer a contract that determines the payment to doctors and doctors decide how many patients to treat in the bargaining scenario doctors and managers strategically negotiate on both the payment to doctors and the number of patients to treat we derive the equilibrium doctors payments and number of treated patients under both scenarios we then derive the optimal contract offered by the government to the hospital in the first stage results show that when the cost of capital is sufficiently low the informational rent is lower and the social welfare is higher in the contracting scenario

fiscal federalism and lobbying abstract which government functions should be decentralized resp centralized once lobbying behavior is taken into account we find that the answer largely depends on how the interests of the regional lobbies are positioned with respect to the function to be decentralized resp centralized when regional lobbies have conflicting interests then lobbying is less damaging for social welfare under centralization than under decentralization on the contrary when regional lobbies have aligned interests then lobbying is less damaging for social welfare under decentralization provided that policy spillovers on the non organized groups are not too strong

transparency and economic policy we provide a two period model of political competition in which voters imperfectly observe the electoral promises made to other voters imperfect observability generates an incentive for candidates to offer excessive transfers even if voters are homogeneous and taxation is distortionary government spending is larger than in a world of perfect observability transfers are partly financed through government debt and the size of the debt is higher in less transparent political systems the model provides an explanation of fiscal churning it also predicts that groups whose transfers are less visible to others receive higher transfers and that imperfect transparency of transfers may lead to underprovision of public goods from the policy perspective the main novelty of our analysis is a separate evaluation of the transparency of spending and the transparency of revenues we show that the transparency of the political system does not unambiguously improve efficiency transparency of spending is beneficial but transparency of revenues can be counterproductive because it endogenously leads to increased wasteful spending

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

pollution claim settlements under private information abstract the classical problem of resolving a nuisance dispute between a pollution generating firm and nearby residents is modelled here as a mechanism design problem we assume that the designer of the mechanism is the firm that it is uncertain about the actual losses suffered by residents and that the initial assignment of property rights is one where each resident is entitled to prevail we derive a profitmaximizing scheme under the individual rationality and incentive compatibility constraints and examine its properties it is shown that the outcomes it yields are sometimes inefficient moreover when many residents are affected by pollution and the degree of uncertainty with respect to the losses they suffer is large these inefficiencies become rampant

backward stealing and forward manipulation in the wto abstract motivated by the structure of wto negotiations we analyze a bargaining environment in which negotiations proceed bilaterally and sequentially under the most favored nation mfn principle we identify backward stealing and forward manipulation problems that arise when governments bargain under the mfn principle in a sequential fashion we show that these problems impede governments from achieving the multilateral efficiency frontier unless further rules of negotiation are imposed we identify the wto nullification or impairment and renegotiation provisions and its reciprocity norm as rules that are capable of providing solutions to these problems in this way we suggest that wto rules can facilitate the negotiation of efficient multilateral trade agreements in a world in which the addition of new and economically significant countries to the world trading system is an ongoing process

analyzing legal regulations in the norwegian life insurance business using a multistage asset liability management model the legal regulations for the life insurance business in norway have recently been and still are under revision the government s intention is to secure the interests of the customers in life insurance companies however there has been debate as to whether the regulations really are in the customers best interest we apply an asset liability management alm model to analyze the implications of the regulations the model is multistage stochastic and integrates assets and liabilities we employ a four stage model to analyze the legal regulations and conclude that the current legal framework is not in the insurance holders best interests

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

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

on the role of confidentiality and deadlines in bilateral negotiations abstract the preference between public and private negotiations for a buyer who sequentially visits two sellers is examined it is shown that the buyer weakly prefers private negotiations so as to create strategic uncertainty about the trade history with substitute goods such uncertainty is valuable only when price offers have short deadlines that prevent a head to head competition with complementary goods strategic uncertainty is valuable to the extent that price coordination becomes a concern for sellers which is likely to be the case when sellers possess high bargaining powers their price offers have short deadlines and or goods are weak complements sellers strategic deadline choices as well as their incentives to disclose information about negotiations are also investigated

optional fixed fees in multilateral vertical relations abstract we examine vertical contracting in a perfect information environment in contrast to mcafee and schwartz mcafee r p schwartz m 1994 opportunism in multilateral vertical contracting nondiscrimination exclusivity and uniformity american economic review vol 84 pp 210 230 we demonstrate that outcomes are efficient if an upstream monopolist has the choice of requiring upfront fixed fee payments or making them optional

on the effectiveness of scenario generation techniques in single period portfolio optimization in single period portfolio selection problems the expected value of both the risk measure and the portfolio return have to be estimated historical data realizations used as equally probable scenarios are frequently used to this aim several other parametric and non parametric methods can be applied when dealing with scenario generation techniques practitioners are mainly concerned on how reliable and effective such methods are when embedded into portfolio selection models in this paper we survey different techniques to generate scenarios for the rates of return we also compare the techniques by providing in sample and out of sample analysis of the portfolios obtained by using these techniques to generate the rates of return evidence on the computational burden required by the different techniques is also provided as reference model we use the worst conditional expectation model with transaction costs extensive computational results based on different historical data sets from london stock exchange market ftse are presented and some interesting financial conclusions are drawn

markets for ownership the prevailing economic theory of the firm based on a property rights perspective has demonstrated that ownership by dispensable outside parties is an inefficient outcome relative to ownership by productive agents in order to better understand observed patterns of ownership this paper considers the outcome of ma rkets for ownership that operate prior to production taking place the main result is that outside parties will often become the equilibrium asset owners this is precisely because but for ownership such parties would not earn rents in contrast productive agents earn rents even when they do not own assets given that their contribution is complementary with other productive agents their willingness to pay for ownership is less than that of an outside party this result is robust to the introduction of moderate levels of inefficiency arising from outside ownership and to a consideration of opportunities for re sale before production begins the main conclusion drawn is that the nature of the operation of markets for ownership stands alongside incentive effects as important predictors of firm boundaries journal of economic literature classification numbers d23 l22

tv wars exclusive content and platform competition in pay tv the article examines incentives for exclusive distribution of premium television programming static analysis shows that a vertically integrated operator with premium programming always supplies this content to the rival distributor using per subscriber fees to soften competition in a dynamic setting with switching costs exclusivity confers a market share advantage benefiting the operator in the future under certain conditions this future benefit outweighs the opportunity cost of forgone wholesale fees making exclusivity the preferred choice alternative dynamic mechanisms are explored identifying essential features the analysis explains the observed incidence of content exclusivity in pay tv and provides guidance for policy makers

the effect of protest votes on the estimates of wtp for use values of recreational sites contingent valuation studies are often characterized by a considerable number of protest responses which may cause selectivity bias on the final estimates for wtp sample selection models can detect and if necessary correct selectivity bias in economic applications where the relevant dependent variable is continuous sample selection models are generally estimated using heckman s 2 step method rather than the fiml estimator either method has its own drawback computational complexity for the fiml method susceptibility to collinearity problems for the 2 step method using data on valuation of forest resources for recreational use we analyse the performance of the two estimators in this application given the presence of some collinearity the fiml is preferred to the 2 step method a procedure is outlined to deal with selectivity problems in similar settings

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

trading between agents for a better match this paper studies externalities that arise when agents can trade outcomes ex post i show that when agents can trade outcomes ex post principals are incentivized to contract with agents ex ante to reduce ex post transfers to outside agents with whom the principals do not directly contract this causes principals to offer agents piece rates that are inefficiently low and lower than the piece rates they would offer if trading was not allowed although trading reduces an agent s effort and could increase the agent s outside option of rejecting a principal s ex ante contract principals ultimately gain from allowing ex post trading because such trading results in outcomes that better match their tastes

concepts technical issues and uses of the russell yasuda kasai financial planning model this paper discusses technical aspects of the russell yasuda kasai financial planning model these include the models for the discrete distribution scenario generation processes for the uncertain parameters of the model the mathematical approach used to develop the infinite horizon end effects part of the model a comparison of algorithms used in the model s solution and a comparison of the multistage stochastic linear programming model with the previous technology static mean variance analysis experience and benefits of the model in yasuda kasai s financial planning process is also discussed

default correlation at the sovereign level evidence from some latin american markets using the eruption of argentina debt crisis in 2001 as a natural experiment we investigated the correlated default at the sovereign level for some latin american countries daily closing market quotes for sovereign credit default swaps cds of argentina brazil mexico and venezuela were obtained from credittrade database using copula approach we observed increased dependences among sovereign cds markets during the crisis period their dependence structures were found to be asymmetric moreover the degree of credit contagion was related to the creditworthiness of the country this study also discussed the implications of these findings for policymakers

evolutionary portfolio selection with liquidity shocks insurance companies invest their wealth in financial markets the wealth evolution strongly depends on the success of their investment strategies but also on liquidity shocks which occur during unfavourable years when indemnities to be paid to the clients exceed collected premia an investment strategy that does not take liquidity shocks into account exposes insurance companies to the risk of bankruptcy when liquidity shocks and low investment payoffs jointly appear therefore regulatory authorities impose solvency restrictions to ensure that insurance companies are able to face their obligations with high probability this paper analyses the behaviour of insurance companies in an evolutionary framework we show that an insurance company that merely satisfies regulatory constraints will eventually vanish from the market we give a more restrictive no bankruptcy condition for the investment strategies and we characterize trading strategies that are evolutionary stable i e able to drive out any mutation

the limits of monopolization through acquisition we address the question of whether competitive acquisition of firms by their rivals can result in complete or partial monopolization of a homogeneous product industry this question is modeled in terms of two distinct three stage noncoopera tive games analysis of subgame perfect pure strategy nash equilibria of these games discloses that under simplifying assumptions monopolization of an industry through acquisition is limited to industries with relatively few firms partial monopolization is either limited in scope or can be completely eliminated by prohibiting any owner from acquiring over 50 percent of the firms in the industry

private contracting with externalities divide and conquer abstract this paper considers the efficacy of divide and conquer strategies in principal agent games involving contracting with externalities we find that whereas divide and conquer offers can arise in equilibrium under some conditions when the principal s offers are publicly observable they cannot arise in equilibrium when the principal s offers are privately observable and the agents hold passive out of equilibrium beliefs this insight applies to technology and platform adoption decisions with network effects labor relations settlement negotiations and input licensing among others

over confidence may reduce negotiation delay abstract when a seller negotiates with multiple buyers how does over confidence affect the timing of trade in this paper we distinguish between over confidence about trade opportunities and over confidence about the terms of trade in bargaining environments without externalities both types of over confidence can cause delays in agreement if externalities are present the two forms of subjective bias have very different impacts on delay in particular over confidence about trade opportunities may reduce bargaining delay

opportunism and menus of two part tariffs we show that a menu of two part tariffs can solve the opportunism problem identified by mcafee and schwartz 1994 in vertical games with sequential contracting provided the sunk costs incurred by the first firm to invest are not too large if the seller were to engage in opportunism with a second firm in an attempt to shift rents from the first firm the first firm could mitigate the dissipation of its rents by choosing from its menu of contract options the tariff with the higher marginal price and lower fixed fee the prospect of the first firm s choosing the wrong two part tariff in the event of opportunism is in some environments sufficient to make opportunism unprofi table for the seller

foreign direct investment in vertically related markets we study an mne s choice of fdi mode in a vertically related market with local input sourcing we show how the market s vertical structure and trading features affect this choice an mne s incentives to expand through cross border acquisition rather than through greenfield investment are stronger in markets with higher upstream bargaining power upstream concentration and unobservable contract terms the opposite holds in markets in which wholesale price contracts instead of two part tariffs are used our welfare analysis suggests that the host country should not always welcome fdi and should discourage fdi through acquisition investissements exterieurs directs sur les marches verticaux dans cet article nous etudions le choix d une entreprise multinationale de proceder a un investissement exterieur direct dans un marche vertical avec sources d approvisionnement locales nous montrons la facon dont la structure verticale et les caracteristiques commerciales du marche ont une incidence sur une telle decision les mesures incitatives offertes aux entreprises multinationales pour se developper par l entremise d acquisitions transfrontalieres plutot que par l investissement dans de nouvelles installations sont plus fortes sur les marches dotes d un pouvoir de negociation et d une concentration en amont plus eleves ainsi que par des conditions contractuelles non observables l inverse s observe sur les marches ou les contrats a prix de gros sont utilises en lieu et place des tarifs binomes en termes de bien etre notre analyse suggere que le pays hote ne devrait pas toujours accueillir les investissements exterieurs directs et devrait decourager ces memes investissements realises par l entremise d acquisitions

formulation of the russell yasuda kasai financial planning model this paper describes the formulation of the russell yasuda kasai financial planning model including the motivation for the model the presentation complements the discussion of the technical details of the financial modeling process and the managerial impact of its use to help allocate the firm s assets over time discussed in carin o et al 1994 1998 respectively the multistage stochastic linear program incorporates yasuda kasai s asset and liability mix over a five year horizon followed by an infinite horizon steady state end effects period the objective is to maximize expected long run profits less expected penalty costs from constraint violations over the infinite horizon scenarios are used to represent the uncertain parameter distributions the constraints represent the institutional cash flow legal tax and other limitations on the asset and liability mix over time

contracts and externalities how things fall apart a single principal interacts with several agents offering them contracts the crucial assumption of this paper is that the outside option payoffs of the agents depend positively on how many uncontracted or free agents there are we study how such a principal unwelcome though he may be approaches the problem of contract provision to agents when coordination failure among the latter group is explicitly ruled out two variants are considered when the principal cannot re approach agents there is a unique equilibrium in which contract provision is split up into two phases in phase 1 simultaneousoffers at good though varying terms are made to a number of agents in phase 2 offers must be made sequentially and their values are discontinuously lower they are close to the very lowest of all the outside options when the principal can repeatedly approach the same agent there is a multiplicity of equilibria in some of these the agents have the power to force delay they can hold off the principal s overtures temporarily but they must succumb in finite time in both models despite beingable to coordinate their actions agents cannot resist an invasion by the principal and hold to their best payoff it is in this sense that things eventually fall apart

naked exclusion an experimental study of contracts with externalities this paper reports the results of an experiment designed to assess the ability of an incumbent seller to profitably foreclose a market with exclusive contracts we use the strategic environment described by rasmusen ramseyer and wiley 1991 and segal and whinston 2000 where entry is unprofitable when sufficiently many downstream buyers sign exclusive contracts with the incumbent when discrimination is impossible the game resembles a stag hunt coordination game in which the buyers payoffs are endogenously chosen by the incumbent seller exclusion occurs when the buyers fail to coordinate on their preferred equilibrium two way non binding pre play communication among the buyers lowers the power of exclusive contracts and induces more generous contract terms from the seller when discrimination and communication are possible the exclusion rate rises divide and conquer strategies are observed more frequently when buyers can communicate with each other exclusion rates are significantly higher when the buyers payoffs are endogenously chosen rather than exogenously given finally secret offers are shown to decrease the incumbent s power to profitably exclude

non cooperative bargaining theory an introduction the paper provides an informal introduction to some of the main themes of the recent literature on non cooperative or sequential bargaining models it focuses in particular on the relationship between the new approach and the traditional axiomatic approach exemplified by nash bargaining theory it illustrates the new insights offered by the non cooperative approach by reference to a detailed analysis of the manner in which the presence of an outside option available to one of the parties will affect the negotiated outcome finally the difficulties which arise in extending this analysis to two person bargaining with incomplete information and to n person bargaining are discussed this is a revised version of the fourth review of economic studies lecture presented in april 1985 at the joint meeting of the association of university teachers of economics and the royal economic society held in oxford the choice of lecturer is made by a panel whose members are currently professors hahn mirrlees and nobay and the paper is refereed in the usual way this paper aims to provide an informal and elementary introduction to an approach to bargaining which has received a great deal of attention over the past few years the approach involves writing down some particular sequence of moves offers and replies to be made over time in the course of negotiations and then looking for a non cooperative equilibrium in the game thus specified in practice a perfect equilibrium or in games of incomplete information a sequential equilibrium while the approach appears at first sight to be very different in spirit from the traditional axiomatic approach in which a bargaining solution is specified by appealing to a number of general requirements which are deemed appropriate on the basis of some a priori considerations the two approaches are in fact complementary while the

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

parametric and semiparametric estimation of sample selection models an empirical application to the female labour force in portugal this paper applies both parametric and semiparametric methods to the estimation of wage and participation equations for married women in portugal the semiparametric estimators considered are the two stage estimators proposed by newey 1991 and andrews and schafgans 1998 the selection equation results are compared using the specification tests proposed by horowitz 1993 horowitz and hardle 1994 and the wage equation results are compared using a hausman test significant differences between the two approaches indicate the inappropriateness of the standard parametric methods to the estimation of the model and for the purpose of policy simulations the greater departure seems to occur in the range of the low values of the index corresponding to a specific group of women copyright 2001 john wiley sons ltd

the timing of contracting with externalities abstract this paper endogenizes the timing of bilateral contracting between one principal and multiple agents in the presence of externalities contracting simultaneously with all agents is optimal for the principal if externalities become weaker the more an agent trades if instead externalities become stronger sequential negotiations might benefit the principal as they lower the agents outside options under some linearity conditions the principal s preferences with respect to different timings of contracting are opposed to their efficiency ranking

a bank asset and liability management model in managing its assets and liabilities in light of uncertainties in cash flows cost of funds and return on investments a bank must determine its optimal trade off between risk return and liquidity in this paper we develop a multiperiod stochastic linear programming model alm that includes the essential institutional legal financial and bank related policy considerations and their uncertainties yet is computationally tractable for realistically sized problems a version of the model was developed for the vancouver city savings credit union for a 5 year planning period the results indicate that alm is theoretically and operationally superior to a corresponding deterministic linear programming model and that the effort required for the implementation of alm and its computational requirements are comparable to those of the deterministic model moreover the qualitative and quantitative characteristics of the solutions are sensitive to the model s stochastic elements such as the asymmetry of cash flow distributions we also compare alm with the stochastic decision tree sdt model developed by s p bradley and d b crane alm is computationally more tractable on realistically sized problems than sdt and simulation results indicate that alm generates superior policies

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

the planting real option in cash rent valuation after entering into a farmland cash rent contract in the fall a tenant farmer has flexibility over the spring crop choice and the input application level failure to account for these options will bias estimates of what farmers should pay to rent land applying monte carlo simulation methods this study investigates the option values for these choices a multivariate gaussian copula mgc is employed to account for dependence among yields and prices results show that the average cash rent valuation for the real option approach is 33 6 higher than that for the conventional net present value npv method in which the input intensity option is 0 9 crop planting sequence is shown to impact the real option value

contracting with externalities the paper studies inefficiencies arising in contracting between one principal and n agents when the utility of each agent depends on all agents trades with the principal when the principal commits to a set of publicly observable bilateral contract offers the arising inefficiency is due entirely to the externalities imposed on non signers in contrast when the principal s offers are privately observed the distortion is due to the externalities given agents equilibrium trades comparison of the two externalities determines the relative efficiency of the two contracting regimes in both cases we show that when n is large each agent can be treated as non pivotal provided that appropriate continuity assumptions are satisfied we also study the case in which the principal can condition each agent s trade on other agents messages we characterize the set of such mechanisms in which each agent s participation is voluntary when the principal can commit to any such mechanism she implements the first best outcome while threatening each deviator with the harshest possible punishment however in the presence of noise that goes to zero slower than n goes to infinity in the limit we obtain a generally inefficient outcome in which each agent feels non pivotal

limited dependent variables in willingness to pay studies applications in health care the appropriate technique for econometric analysis of wtp willingness to pay data is an issue which has not been addressed in many studies of wtp for health and health care this paper argues that whether an open ended question or a payment scale approach is adopted the way in which wtp is recorded means that limited dependent variable models are more appropriate than standard regression analysis data from an open ended question on wtp for maternity care contain a large proportion of zeros and the evidence suggests that a two part specification performs better than ols or a standard tobit model if the payment scale method is adopted our argument suggests that grouped data regression is an appropriate econometric technique in practice with data from a study in northern norway the results from ols and grouped data regression are broadly similar

why higher takeover premia protect minority shareholders posttakeover moral hazard by the acquirer and free riding by the target shareholders lead the former to acquire as few sharcs as necessary to gain control as moral hazard is most severe under such low ownership concentration inefficiencies arise in successful takeovers moreover share supply is shown to be upward sloping rules promoting ownership concentration limit both agency costs and the occurrence of takeovers furthermore higher takeover premia induced by competition translate into higher ownership concen tration and are thus beneficial finally one share one vote and simple majority are generally not optimal and socially optimal rules need not emerge through private contracting

technology adoption in the presence of network externalities we analyze technology adoption in industries where network externalities are significant the pattern of adoption depends on whether technologies are sponsored a sponsor is an entity that has property rights to the technology and hence is willing to make investments to promote it key findings include the following 1 compatibility tends to be undersupplied by the market but excessive standardization can occur 2 in the absence of sponsors the technology superior today has a strategic advantage and is likely to dominate the market 3 when one of two rival technologies is sponsored that technology has a strategic advantage and may be adopted even if it is inferior 4 when two competing technologies both are sponsored the technology that will be superior tomorrow has a strategic advantage

vertical contracting with informational opportunism we consider vertical contracting arrangements between a manufacturer and a retailing network when retailers have private information and the organization is run through bilateral contracts we highlight a new form of informational opportunism arising when the manufacturer manipulates information learned separately in each relationship we characterize the set of allocations robust to such opportunism by means of simple ex post incentive compatibility constraints those constraints limit the manufacturer s ability to use yardstick competition among retailers they simplify contracts and restore a rent efficiency trade off even with correlated information we show that sell out contracts are optimal under a wide range of circumstances

land and stock prices in japan in late 1991 the total land value in japan was estimated at nearly 20 trillion this was more than 20 percent of the world s wealth or to put it in some other contexts about double the world s equity markets or half again as large as the world s bond markets japanese land was then valued at about five times that of the united states the land under the emperor s palace which is about three quarters of a square mile was estimated to be worth about the same as all the land in california or in canada real estate assets of japanese corporations grew by 2 8 trillion from 1986 to 1988 an increase in valuation roughly equal to the size of the japanese gross national product an equally dramatic rise in stock prices accompanied the rise in land prices at its peak in december 1989 the japanese stock market had a value of about 4 trillion which was about 44 percent of the world s equity market capitalization to put that figure in perspective the value of the equity on all the stock exchanges in the united states in august 1992 was less than 5 trillion but then from its peak in december 1989 to august 1992 the japanese stock market fell by over 60 percent various indices of speculative land values fell a similar amount meanwhile other land prices industrial commercial residential as measured by various indices fell 15 20 percent this paper discusses the rise of japanese stock and land prices in the past four decades and their dramatic decline in the early 1990s to what extent can

coordination and bargaining power in contracting with externalities abstract building on genicot and ray g genicot d ray contracts and externalities how things fall apart j econ theory 131 2006 71 100 we develop a model of non cooperative bargaining that combines the two main approaches in the literature of contracting with externalities the offer game in which the principal makes simultaneous offers to the agents and the bidding game in which the agents make simultaneous offers to the principal allowing for agent coordination we show that the outcome of our bargaining procedure may differ remarkably from those of the offer and the bidding games in particular we find that bargaining can break agents coordination and that the principal s payoff can be decreasing in his own bargaining power

multi period stochastic optimization models for dynamic asset allocation abstract institutional investors manage their strategic asset mix over time to achieve favorable returns subject to various uncertainties policy and legal constraints and other requirements one may use a multi period portfolio optimization model in order to determine an optimal asset mix the concept of scenarios is typically employed for modeling random parameters in a multi period stochastic programming model and scenarios are constructed via a tree structure recently an alternative stochastic programming model with simulated paths was proposed by hibiki hibiki n 2001b a hybrid simulation tree multi period stochastic programming model for optimal asset allocation in takahashi h ed the japanese association of financial econometrics and engineering jafee journal 89 119 in japanese hibiki n 2003 a hybrid simulation tree stochastic optimization model for dynamic asset allocation in scherer b ed asset and liability management tools a handbook for best practice risk books pp 269 294 and it is called a hybrid model the advantage of the simulated path structure compared to the tree structure is to give a better accuracy to describe uncertainties of asset returns in this paper we compare the two types of multi period stochastic optimization models and clarify that the hybrid model can evaluate and control risk better than the scenario tree model using some numerical tests according to the numerical results an efficient frontier of the hybrid model with the fixed proportion strategy dominates that of the scenario tree model when we evaluate them on simulated paths moreover optimal solutions of the hybrid model are more appropriate than those of the scenario tree model

semiparametric estimation of the intercept of a sample selection model this paper provides a consistent and asymptotically normal estimator for the intercept of a semiparametrically estimated sample selection model the estimator uses a decreasingly small fraction of all observations as the sample size goes to infinity as in heckman 1990 in the semiparametrics literature estimation of the intercept has typically been subsumed in the nonparametric sample selection bias correction term the estimation of the intercept however is important from an economic perspective for instance it permits one to determine the wage gap between unionized and nonunionized workers decompose the wage differential between different socioeconomic groups e g male female and black white and evaluate the net benefits of a social programme

optimal savings management for individuals with defined contribution pension plans abstract the paper provides some guidelines to individuals with defined contribution dc pension plans on how to manage pension savings both before and after retirement we argue that decisions regarding investment annuity payments and the size of death sum should not only depend on the individual s age or time left to retirement nor should they solely depend on the risk preferences but should also capture 1 economical characteristics such as current value on the pension savings account expected pension contributions mandatory and voluntary and expected income after retirement e g retirement state pension and 2 personal characteristics such as risk aversion lifetime expectancy preferable payout profile bequest motive and preferences on portfolio composition specifically the decisions are optimal under the expected crra utility function and are subject to the constraints characterizing the individual the problem is solved via a model that combines two optimization approaches stochastic optimal control and multi stage stochastic programming the first method is common in financial and actuarial literature but produces theoretical results however the latter which is characteristic for operations research has practical applications we present the operations research methods which have potential to stimulate new thinking and add to actuarial practice

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

network effects and environmental externalities do clean technologies suffer from excess inertia abstract we study the diffusion of a clean substitute to a dirty durable in a dynamic model consumer utility of both durables increases in their respective market shares due to network effects first we characterize the optimal dirty good tax the tax should achieve a long run optimal division of the market between the two goods along the transition path to this steady state the optimal tax depends on the current and future market shares of the clean durable thus even if the marginal environmental damage from an additional dirty durable is constant the optimal tax should not be constant second we study whether excess inertia can occur if the emission tax is not optimally set we then find that a constant tax that only accounts for the environmental damage caused by the dirty good may lead to excess inertia excess inertia could happen even if the clean technology is proprietary and the technology owner has incentives to sponsor the initial market diffusion of the technology

applying the copula approach to sample selection modelling the limited availability of tractable multivariate distributions undermines the validity of the standard parametric approach to sample selection modelling copula distributions can be very useful in situations where the applied researcher has a prior on the distributional form of the margins since the modelling of the latter is separated from that of the dependence structure the present article first presents an application to female work data afterwards the approach is analysed in an application to contingent valuation data on recreational values of forests it is shown that the copula approach is especially beneficial in case of strong departures from the hypothesis of normality

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

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

an optimal auction with identity dependent externalities we analyze the problem of a seller of multiple identical units of a good who faces a set of buyers with unit demands private information and identity dependent externalities we derive the seller s optimal mechanism and characterize its main properties we show that the probability that a buyer obtains a unit is an increasing function of the externalities he generates and enjoys also the seller s allocation of the units of the good need not be ex post efficient as an illustration we apply the model to the problem faced by a developer of a shopping mall who wants to allocate and price its retail space among anchor and non anchor stores we show that a commonly used sequential mechanism is not optimal unless externalities are large enough

back testing the performance of an actively managed option portfolio at the swedish stock market 1990 1999 we build an investment model based on stochastic programming in the model we buy at the ask price and sell at the bid price we apply the model to a case where we can invest in a swedish stock index call options on the index and the risk free asset by reoptimizing the portfolio on a daily basis over a ten year period it is shown that options can be used to create a portfolio that outperforms the index with ex post analysis it is furthermore shown that we can create a portfolio that dominates the index in terms of mean and variance i e at given level of risk we could have achieved a higher return using options

asymmetric information bargaining problems with many agents a yes or no decision must be made about some issue all agents must agree the coase theorem asserts that the efficient outcome will always result suppose the value positive or negative that an individual attaches to an affirmative decision is privately known to that individual it is proved under very mild conditions that with independent types as the number of agents increases the probability of an affirmative efficient decision goes to zero an example in which it is common knowledge that an affirmative decision is efficient and yet the probability of such a decision goes to zero is given

how to license intangible property we examine the optimal licensing strategy of a research lab selling to firms who are product market competitors we consider an independent lab as well as a research joint venture we show that 1 demands are interdependent and hence the standard price mechanism is not the profit maximizing licensing strategy 2 the seller s incentives to develop the innovation may be excessive 3 the seller s incentives to disseminate the innovation typically are too low 4 larger ventures are less likely to develop the innovation and more likely to restrict its dissemination in those cases where development occurs and 5 a downstream firm that is not a member of the research venture is worse off as a result of the innovation

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

endogenous games and mechanisms side payments among players we characterize the outcomes of games when players may make binding offers of strategy contingent side payments before the game is played this does not always lead to efficient outcomes despite complete information and costless contracting the characterizations are illustrated in a series of examples including voluntary contribution public good games cournot and bertrand oligopoly principal agent problems and commons games among others

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

a noncooperative coalitional bargaining game with random proposers abstract we extend the stahl rubinstein s alternating offer model ton person coalitional bargaining the key feature of the model is the random selection of proposers at every round no delay of agreement occurs in equilibrium for a super additive game in contrast to the fixed order model of chatterjeeet al rev econ stud 60 1993 463 477 when the discount factor of future payoffs is sufficiently high the agreement on the grand coalition is reached if and only if it has the largest value per capita among all coalitions moreover in the limit as the discount factor goes to one all players divide equally the value of the grand coalition regardless of who makes a proposal journal of economic literatureclassification numbers c72 c73 c78

modelling zero values and protest responses in contingent valuation surveys in contingent valuation surveys the category of zero bidders refers to individuals that are not willing to pay anything for the programme under analysis specific questions can help to identify true zero values coming from people that are indifferent to the programme separately from protest responses the latter are generally excluded from the analysis this paper introduces a mixture sample selection model that takes into account both zero values and protest responses in the estimates the model is applied to the valuation of a traffic calming scheme aimed at reducing risks for residents in three villages in the north east of england

the performance of stochastic dynamic and fixed mix portfolio models the purpose of this paper is to demonstrate how to evaluate stochastic programming models and more specifically to compare two different approaches to asset liability management the first uses multistage stochastic programming while the other is a static approach based on the so called constant rebalancing or fixed mix particular attention is paid to the methodology used for the comparison the two alternatives are tested over a large number of realistic scenarios created by means of simulation we find that due to the ability of the stochastic programming model to adapt to the information in the scenario tree it dominates the fixed mix approach

livestock disease indemnity design when moral hazard is followed by adverse selection averting or limiting the outbreak of infectious disease in domestic livestock herds is an economic and potential human health issue that involves the government and individual livestock producers producers have private information about preventive biosecurity measures they adopt on their farms prior to outbreak ex ante moral hazard and following outbreak they possess private information about whether or not their herd is infected ex post adverse selection we investigate how indemnity payments can be designed to provide incentives to producers to invest in biosecurity and report infection to the government in the presence of asymmetric information we compare the relative magnitude of the first and second best levels of biosecurity investment and indemnity payments to demonstrate the tradeoff between risk sharing and efficiency and we discuss the implications for status quo u s policy