environmental policy instruments in an international duopoly with feedback investment strategies abstract this paper analyses the effects of the environmental policy instruments taxes and standards on the investment behaviour of firms in the context of an international duopoly two production factors are considered the capital stock and a polluting input the government of each country values high profits for its firm and a good environmental quality through standards on the polluting input firms get commitment on output which is not the case under taxes standards thus seem a better environmental policy instrument because for the same use of the polluting input taxes lead the duopolists to higher investment with lower profits this result was derived in a two stage game model it was confirmed in a differential game model with open loop strategies the paper shows that in a differential game model with feedback strategies an effect occurs that counteracts the first effect the cause of this is that taxes induce substitution between capital and the polluting input the conclusion is that under taxes firms invest more due to the absence of commitment but invest less due to substitution between the inputs the net effect depends on the values of the parameters taxes are better than standards for low rates of depreciation and discount for low investment costs and for high productivity of capital

a characterization of erratic dynamics in the overlapping generations model abstract in this paper we characterize and give examples o wide classes of utility functions which generate erratic dynamics in the standard deterministic overlapping generations model erratic dynamics refers to feasible trajectories which are bounded but which do not converge to stationary points or periodic orbits we show that such trajectories are pareto efficient we introduce credit into the model and show how a constant credit expansion rate can result in erratic trajectories in prices and the real value of credit finally we briefly discuss certain technical aspects of the mathematics used and the statistical nature of the dynamics that can arise from deterministic dynamical systems

differential games with nonconvexities and positive spillovers abstract this paper deals with differential games characterized by nonconvexities and increasing returns the objective function of the players is convex in the control variables and nonconvex in the state variables we employ the open loop nash equilibrium solution concept this framework enables us to handle games characterized by positive spillovers and strategic complementarities e g capital accumulation differential games with learning by doing where the knowledge available to a firm is given by the knowledge accumulated by the economy as a whole

dynamic game results of the acquisition of new technology open and closed loop nash strategies are derived and analyzed for a differential game in which two competing firms choose prices and productive capacity where new technology reduces a firm s unit operating cost using an open loop strategy a firm makes an irreversible commitment to a future course of action for example a contract with a labor union may force a firm to commit to maintaining its entire workforce regardless of its competitor s future realized behavior in contrast using a closed loop strategy a firm s decisions evolve over time continuously responding to the competitor s behavior the dynamic nash strategies obtained for the closed loop model exhibit a more restricted acquisition of new technology and a greater reduction of existing capacity relative to the open loop solutions in addition the dynamic nash price to be charged for output is higher in the closed as opposed to open loop competitive environment numerical solutions are presented to demonstrate that if both firms apply the closed loop approach each will earn higher profits than if one or both firms choose an open loop strategy

cyclical equilibria in multi sector productive economies the role of substitution and factor intensity abstract the paper examines the existence of cyclical perfect foresight equilibria in a two sector overlapping generations economy with production in which both goods enter consumption conditions for the existence of two types of cyclical equilibra are obtained in terms of elasticities of substitution in production and consumption factor shares in production and expenditure shares in consumption the role of substitution possibilities and factor intensities is highlighted it is shown that factor intensity assumptions are not enough to rule out cyclical equilibria and that limit cycles may exist for substantial amounts of substitution possibilities in production what matters is the relative sizes of the consumption and production elasticities the results are illustrated using ces functions a dynamical simulation of an economy which exhibits a hopf cycle is presented

the tragedy of the commons and economic growth why does capital flow from poor to rich countries we analyze a differential game in which all interest groups have access to a common capital stock we show that the introduction of a technology that has inferior productivity but enjoys private access may ameliorate the tragedy of the commons we use this model to analyze capital flight in many poor countries property rights are not well defined since safe bank accounts in rich countries the inferior technology are available to citizens of these countries they engage in capital flight we show that the occurrence of capital flight does not imply that opening the capital account reduces growth and welfare

anticipated policy and endogenous growth in a small open monetary economy abstract this paper analyzes the effects of a preannounced change in the growth rate of credit in a small open economy the model based on an endogenous growth model introduces the adjustment costs for investment and the role of money in the production function and highlights the dynamic behavior of an open economy we show that an increase in the rate of anticipated credit growth lowers the steady growth rate of capital real money balances and real output we also find that the rate of depreciation of the domestic currency will rise steadily toward its stationary level the anticipated domestic credit growth hence exhibits monetary nonsuperneutrality in both the rate and the level of output in the intermediate and the long run

capital accumulation games of infinite duration abstract consider a market in which firms accumulate capital according to the nerlove arrow capital accumulation equation each player chooses a path of investment and thus an induced path of capital to maximize his total discounted profits which depend on his own capital and the capital stocks of his rivals existence is proved for such a nonzero sum infinite horizon differential game and conditions under which the game converges to a particular stationary point regardless of the initial conditions are shown thus the game possesses the property of conditional global asymptotic stability

a dynamic general equilibrium analysis of deviations from the laws of one price abstract using disaggregated west german prices this study documents movements in relative export and producer prices and in relative import and producer prices which are variable and highly autocorrelated this suggests the presence of time varying persistent deviations from the laws of one price perfect competition monopoly and monopolistic competition with constant mark up pricing are inconsistent with the variability in relative export and producer prices furthermore cournot oligopoly is inconsistent with the variability in relative import and producer prices a dynamic general equilibrium model with differentiated oligopolistic competition and strategic pricing is shown to generate variable and persistent movements in both measures of relative prices

computational economics and economic theory substitutes or complements abstract this essay examines the idea and potential of a computational approach to theory discusses methodological issues raised by such computational methods and outlines the problems associated with the dissemination of computational methods and the exposition of computational results we argue that the study of a theory need not be confined to proving theorems that current and future computer technologies create new possibilities for theoretical analysis and that by resolving these issues we will create an intellectual atmosphere in which computational methods can make substantial contributions to economic analysis

on the co existence of conventions abstract recent stochastic evolutionary models have shown that the most likely outcome when the probability of a mutation is sufficiently small is coordination on the risk dominant strategy rather than on the payoff dominant one this paper looks at the consequences of player movement between locations when there are constraints which limit the number of agents who can reside at each location if the constraints are tight then the risk dominance result continues to hold however we show that when sufficient movement is possible the most likely outcome involves a mixed state in which agents at different locations coordinate on different strategies in the asymmetric case it is the location with the tighter constraint that coordinates on the payoff dominant strategy journal of economic literature classification numbers c72 c73 d83

open loop and feedback models of dynamic oligopoly abstract a simple method of estimating the degree of oligopoly power in dynamic markets using either open loop or feedback subgame perfect strategies is developed new theoretical results are presented for families of oligopoly models differences between discrete time and continuoustime models and open loop and feedback models are demonstrated the effects of increasing the number of firms or adjustment costs are examined

oligopoly equilibria in nonrenewable resource markets abstract most nash cournot oligopoly models of nonrenewable resources apply open loop equilibrium concepts and are based on physical resource depletion this paper studies feedback equilibria and economic depletion assuming affine quadratic functional forms the existence uniqueness and explicit solutions for the equilibria are derived for duopoly and n player oligopoly with multiple resource stocks for the cases of nonquadratic criteria we develop a numeric solution scheme for the nash feedback equilibrium this scheme is an application of a discrete time discrete state controlled markov chain approximation method originally developed for solving deterministic and stochastic dynamic optimization problems in our nash cournot equilibrium the degree of concentration in supply declines over time whereas the previous models with physical depletion and open loop equilibrium concepts predict that a nash cournot resource market will develop in the direction of monopoly supply

a differential game model of a market of substitutable products abstract modern industrial organization often classifies groups of differentiated products that are fairly good substitutes to belong to the same market this paper develops a differential game model of a market of substitutable products to avoid the problem of time inconsistency we solve a feedback nash equilibrium solution for the game a set of state dependent equilibrium strategies is derived extensions of the model to a stochastic formulation and to an infinite time horizon specification are also provided

an equilibrium selection theory of monopolization we develop a duopoly model in which firms compete for the market e g investing in process innovation or product development as well as in the market e g setting quantities or prices competition for the market generates multiple equilibria that differ in the firms investment levels relative size and profitability we show that monopolization that affects competition in the market can act as an equilibrium selection device in competition for the market in particular it eliminates equilibria that are undesirable for the monopolizing firm while not generating new equilibria this result complicates the task of determining whether a firm s dominance in a given market is the result of fair competition or unlawful monopolization we discuss a number of implications for antitrust policy and litigation and illustrate these by means of two well known antitrust cases

composition of r d and technological cycles abstract this paper investigates the existence of technological cycles that arise endogenously from certain tradeoffs between research and development inherent in the technological features of r d production it analyzes the composition of r d expenditures and models the associated internal structure and dynamics of the innovation process explicitly the model includes externalities and cumulative aspects of r d processes the discussion is initially developed in a deterministic setting for both the first best and the market cases the dynamics leading to optimal cycles are fully explored for specific examples results are given with regard to 1 i level of research investment 2 ii stability of steady states and cycles and 3 iii amplitude of cycles extensions to a stochastic setting are also presented

simple and clever decision rules for a model of evolution abstract under the decision rule specified by kandori mailath and rob 1993 kandori m mailath g j rob r 1993 learning mutation and long run equilibria in games econometrica 61 29 56 myopic adjustment can lead to surprising results including coordination on strictly dominated strategies we show that under an alternative decision rule convergence to nash equilibrium is guaranteed moreover if rare mutations are introduced risk dominant equilibria always correspond to long run equilibria

strategic investment and conjectural variations abstract this paper analyzes investment decisions under the alternative assumptions of competitive collusive open loop non cooperative and feedback non cooperative behavior steady state capital stocks prices and outputs are obtained and compared the paper shows that one of the linear feedback equilibrium decision rule coefficients is a dynamic version of a contemporaneous conjectural variation the same decision rule coefficients are shown to imply a particular value for the contemporaneous conjecture the implied conjecture embodies subgame perfection and approaches the competitive value as the number of firms in the industry increases

time consistent protection with learning by doing abstract can a government induce efficiency gains in his domestic industry by protecting it against foreign competition would such trade protection be time consistent the present paper builds a dynamic equilibrium model that accounts for learning by doing effects that link firms strategies over time the model shows that the existence of dynamic economies of scale suffices to overcome the traditional government s lack of commitment of its tariff policy this paper compares the infinite horizon markov perfect equilibrium of this game with the dynamic equilibrium under commitment as well as the static nash equilibrium equilibrium strategies are derived in closed form by solving a linear quadratic differential game optimal trade policy involves higher tariff levels than in the static setup in order to account for future gains in efficiency under reasonable assumptions the unique stable mpe is characterized by a domestic price and tariff that decrease as experience accumulates thus supporting the future liberalization of trade as an equilibrium feature of this dynamic game

a contribution to the theory of business cycles an economy consisting of identical perfectly competitive firms with real liquidity costs and a one period production lag has a locally unstable stationary equilibrium with complex eigenvalues for a wide range of parameters monetary policy aimed at stabilizing real balances can support nonstationary equilibrium paths that converge to a limit cycle which has keynesian features the first welfare theorem does not hold because the price level appears in the production function through liquidity costs so that production has a positive externality

nonlinear strategies in dynamic duopolistic competition with sticky prices abstract we discuss nonlinear strategies in an infinite horizon duopoly game with sticky prices where firms maximize their discounted sum of profit we construct a stationary feedback equilibrium without guessing value functions and feedback strategies that solve the hamilton jacobi equation for this purpose we study the auxiliary equation that is derived from the hamilton jacobi equation we show that the domain of the state space plays an crucial role in characterizing feedback equilibria and discuss several implications of this observation in particular we find that when the upper bound of the state space is not very high previously unknown feedback equilibria emerge

aggregation of heterogeneous time preferences we examine an economy whose consumers have different discount factors for utility possibly not exponential we characterize the properties of efficient allocations of resources and of the shadow prices that would decentralize such allocations we show in particular that the representative agent has a decreasing discount rate when as is usually posited all of a group s members have a constant discount rate and decreasing absolute risk aversion preferences we also identify conditions that lead the representative agent to have a rate of impatience that decreases with gross domestic product per capita

comparing solution methods for dynamic equilibrium economies this paper compares solution methods for dynamic equilibrium economies the authors compute and simulate the stochastic neoclassical growth model with leisure choice using undetermined coefficients in levels and in logs finite elements chebyshev polynomials second and fifth order perturbations and value function iteration for several calibrations the authors document the performance of the methods in terms of computing time implementation complexity and accuracy and they present some conclusions about their preferred approaches based on the reported evidence

equilibrium models displaying endogenous fluctuations and chaos abstract this paper surveys current developments in dynamic general equilibrium theory concerned with conditions under which endogenous fluctuations are possible existing contributions are divided into two classes the larger one consists of models with a unique perfect foresight equilibrium while the second includes models where equilibrium is indeterminate and the set of equilibria involving endogenous fluctuations includes sunspots equilibria while the two classes of models involve oscillations of different natures and with different policy implications we show that both are consistent with optimizing behavior and competitive equilibrium

the law of the few the law of the few refers to the following empirical phenomenon in social groups a very small subset of individuals invests in collecting information while the rest of the group invests in forming connections with this select few in many instances there are no observable dierences in characteristics between those who invest in information and those who invest in forming connections this paper shows that the law of few naturally emerges in environments with identical rational agents we develop a strategic game in which players have the opportunity to invest in collecting information as well as in investing in bilateral connections with others we find that every strict equilibrium of this game exhibits the law of the few we also show that this pattern of social dierentiations is ecient in some cases

sustaining cooperation in a differential game of advertising goodwill accumulation abstract the paper suggests a differential game of advertising competition among three symmetric firms played over an infinite horizon the objective of the research is to see if a cooperative agreement among the firms can be sustained over time for this purpose the paper determines the characteristic functions value functions of individual players and all possible coalitions we identify an imputation that belongs to the core using this imputation guarantees that in any subgame starting out on the cooperative state trajectory no coalition has an incentive to deviate from what was prescribed by the solution of the grand coalition s optimization problem

migration and the evolution of conventions we study an evolutionary model where agents are locally matched to play a symmetric coordination game opportunities to adjust strategy and location arrive asynchronously and infrequently and cannot be coordinated our results on the short run co existence of different conventions and long run efficiency depend upon a condition on off equilibrium payoffs introduced by aumann in a pure coordination game efficient and inefficient conventions may co exist at different locations in the short run and inefficient conventions are stochastically stable in a stag hunt game there is neither short run coexistence nor long run inefficiency

dynamic duopoly with adjustment costs a differential game approach abstract this paper develops a differential game model of duopoly in which firms incur costs associated with how fast they change their level of output the analysis solves for a subgame perfect equilibrium to the model in which the steady state level of output lies strictly between the static cournot and perfect competition solutions furthermore we demonstrate that the limit game in which the speed of adjustment parameter approaches zero does not tend toward the static cournot equilibrium

dynamic oligopoly in the rice export market a linear quadratic dynamic oligopoly model is used to estimate the competitiveness of the rice export market the model nests various market structures using either open loop or feedback strategies the estimated feedback model implies a less competitive market structure than the estimated open loop model the rice export market is oligopolistic but it is closer to competitive than collusive copyright 1989 by mit press

the impact of lead time on capital investments abstract we study equilibrium investment strategies of firms competing in stochastic dynamic market settings and facing two types of investment structures investment with significant lead time or time to build and investment without or minor lead time we investigate how investment behavior changes when investment is subject to time to build versus when it is not we characterize equilibrium investment strategies under several information structures and compare results to the social optimum we offer some new results the model predicts that controlling for demand and production and investment costs investments and outputs can be higher in progressive industries which often exhibit time to build than in fast paced industries where time to build is insignificant furthermore for both investment types investment with or without time to build we offer a novel equilibrium in which firms incrementally invest this behavior is driven by demand uncertainty and capacity constraints also expected outputs are lower than cournot outputs as firms face uncertainty moreover the amount of uncertainty has different effects over investment types

the voracity effect abstract we analyze an economy that lacks a strong legal political institutional infrastructure and is populated by multiple powerful groups powerful groups dynamically interact via a fiscal process that effectively allows open access to the aggregate capital stock in equilibrium this leads to slow economic growth and a voracity effect by which a shock such as a terms of trade windfall perversely generates a more than proportionate increase in fiscal redistribution and reduces growth we also show that a dilution in the concentration of power leads to faster growth and a less procyclical response to shocks jel f43 o10 o23 o40

can leviathan governments mitigate the tragedy of the commons this paper explores the conjecture whether the leviathan motive of politicians to tax for the purpose of raising revenues rather than for benevolent pigovian motives helps to overcome the inefficiency of international pollution spillovers such as in the cases of acid rain and global warming it turns out that this conjecture is true in a static context that captures flow externalities e g acid rain as long as environmental damages are not too high in contrast leviathan motives aggravate the already existing inefficiency in the case of stock externalities e g global warming despite probably high taxes at the beginning

constrained interactions and social coordination we consider a co evolutionary model of social coordination and network formation where agents may decide on an action in a 2x2 coordination game and on whom to establish costly links to we find that a payoff domination convention is selected for a wider parameter range when agents may only support a limited number of links as compared to a scenario where agents are not constrained in their linking choice the main reason behind this result is that whenever there is a small cluster of agents playing the efficient strategy other players want to link up to those layers and choose the efficient action

constrained mobility and the evolution of efficient outcomes we study an evolutionary model akin to the one studied in anwar 2002 where a set of agents use myopic best response learning to i determine their action in a 2 2 coordination game and ii to choose on which of multiple islands to interact we focus on the case where the number of agents maximally allowed on each islands is constrained we extend anwar s original analysis by considering the case when there may be more than two islands we find that if the constraints are such that one island may be empty universal coordination on the payoff dominant action is possible in the long run if the constraints are such that all islands will be full then for relatively mild constraints and apart from special cases the coexistence of conventions will occur with one island coordinating on the risk dominant action and all remaining islands coordinating on the payoff dominant action for relatively stringent constraints all agents will play the risk dominant action

markov puppy dogs and related animals abstract it is shown that steady state markov perfect equilibria of discrete time infinite horizon quadratic adjustment cost games differ from equilibria of their infinitely repeated counterpart games with zero adjustment costs even though no adjustment costs are paid in the steady state in contrast to continuous time games the limit of these equilibria as adjustment costs approach zero is the same as the equilibria of their static counterpart games a classification scheme is presented and it is shown that the taxonomy is identical to that of analogous two stage games such as those analyzed by fudenberg and tirole american economic review papers and proceedings 1984 74 361 366 this classification is useful in that it implies that steady state equilibria need not be explicitly calculated to analyze qualitatively the effects of adjustment costs in strategic environments it is also argued that estimated conjectural variations parameters may capture a well defined property of strategic interaction in a dynamic game

wealth distribution and aggregate time preference markov perfect equilibria in a ramsey economy abstract we study markov perfect nash equilibria mpne of a ramsey cass koopmans economy in which households are aware of their influence on prices the ramsey conjecture fails to hold such that households other than the most patient one own positive wealth in the steady state this confirms results that have been derived in the same model using an open loop equilibrium concept in contrast to the competitive and the open loop equilibrium the steady state of the mpne depends on the utility functions of the households since the mpne cannot be determined analytically a high order least squares projection method is employed

a differential oligopoly game with differentiated goods and sticky prices we investigate a dynamic oligopoly game where goods are differentiated and prices are sticky we study the open loop and the closed loop memoryless nash equilibrium and show that the latter equilibrium entails a larger level of steady state production as compared to the former both equilibria entail a larger level of production in steady state than the static game we also study the effects of price stickiness and product differentiation upon the steady state equilibrium allocation and profits the per firm equilibrium output is increasing in both product differentiation and price stickiness while profits are increasing in both product differentiation and the speed of price adjustment the steady state social welfare monotonically increases in the speed of price adjustment and the overproduction entailed by dynamic competition has beneficial effect from a social standpoint

anticipated inflation and the capital stock in a cash in advance economy abstract an economy is constructed in which the steady state capital stock is inversely related to the rate of inflation as a result that is directly opposite the usual conclusion

equilibrium cycles in an overlapping generations economy with production abstract perfect foresight equilibrium trajectories of an overlapping generations model with production may include stable or unstable invariant closed curves these orbits are detected using the hopf bifurcation theorem where the parameter of bifurcation is purely technological the paper also proves that there is a stabilization policy that completely eliminates the cycle finally using a c e s production function it is shown that the range of values of the elasticity of substitution between capital and labor for which cycles may exist is bounded above

n firm oligopolies with production adjustment costs best responses and equilibrium abstract n firm single product oligopolies will be examined without product differentiation and with production adjustment costs the best response functions of the firms will be first determined in terms of the outputs of the rest of the industry and the firm s own outputs of the previous time period this function is always decreasing not necessarily continuous and might have two different values then the best response will be determined when the output of the rest of the industry is replaced by the output of the entire industry we will show that this function might have infinitely many values leading to infinitely many equilibria a complete description of the equilibrium set will also be given the theoretical findings will be illustrated with the case of linear price and linear cost functions

the evolution of consistent conjectures in this paper we model the evolution of conjectures in an economy consisting of a large number of firms which meet in duopolies the duopoly game is modelled by the conjectural variation cv model an evolutionary process leads to more profitable conjectures becoming more common payoff monotonic dynamics under this class of selection dynamics convergence occurs to a small set of serially undominated strategies containing the consistent conjecture this set can be made arbitrarily small by appropriate choice of the strategy set if the game is dominance solvable then the dynamics converge globally to the unique attractor

open loop equilibria and perfect competition in option exercise games the investment boundaries defined by grenadier 2002 for an oligopoly investment game determine equilibria in open loop strategies as closed loop strategies they are not equilibria because any firm by investing sooner can preempt the investments of other firms and expropriate the growth options the perfectly competitive outcome is produced by closed loop strategies that are mutually best responses in this equilibrium the option to delay investment has zero value and the simple npv rule is followed by all firms the author 2009 published by oxford university press on behalf of the society for financial studies all rights reserved for permissions please e mail journals permissions oxfordjournals org oxford university press

collusion and dynamic under investment in quality in a dynamic game of investment in product quality i investigate whether collusive underinvestment equilibria can be supported by the threat of escalation in investment outlays when there are no spillovers underinvestment equilibria exist even though by deviating a firm can gain a persistent strategic advantage when there are strong spillovers underinvestment equilibria fail to exist a weakening of patent protection can thus lead to more investment in equilibrium a nonfragmentation result is shown to hold in all free entry equilibria industry concentration is bounded away from zero no matter how large the market and despite the existence of underinvestment equilibria

endogenous networks social games and evolution abstract this paper studies a social game where agents choose their partners as well as their actions players interact with direct and indirect neighbors in the endogenous network we show that the architecture of any nontrivial nash equilibrium is minimally connected and equilibrium actions approximate a symmetric equilibrium of the underlying game we apply the model to analyze stochastic stability in 2 2 coordination games we find that long run equilibrium selection depends on a trade off between efficiency and risk dominance due to the presence of scale effects arising from network externalities our results suggest a general pattern of equilibrium selection

capacity investment preemption and commitment in an infinite horizon model the commitment value of capacity is analyzed in an infinite horizon duopoly model the paper focuses on the role of alternative behavioral assumptions about the ability of firms to commit to investment paths each firm s investment strategy in a feedback nash equilibrium is shown to be a decreasing function of its rival s current capacity this creates an incentive for a firm to expand its capacity to preempt subsequent rival investment in a precommitment equilibrium there are no incentives to invest preemptively as a consequence steady state capacity levels are greater in a feedback nash equilibrium than in a precommitment equilibrium copyright 1987 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

altruists egoists and hooligans in a local interaction model the authors study a population of agents each of whom can be an altruist or an egoist altruism is a strictly dominated strategy agents choose their actions by imitating others who earn high payoffs interactions between agents are local so that each agent affects and is affected by only his neighbors altruists can survive in such a world if they are grouped together so that the benefits of altruism are enjoyed primarily by other altruists who then earn relatively high payoffs and are imitated altruists continue to survive in the presence of mutations that continually introduce egoists into the population copyright 1998 by american economic association

a strategic model of social and economic networks we study the stability and efficiency of social and economic networks when self interested individuals can form or sever links first for two stylized models we characterize the stable and efficient networks there does not always exist a stable network that is efficient next we show that this tension persists generally to assure that there exists a stable network that is efficient one is forced to allocate resources to nodes that are not responsible for any of the production we characterize one such allocation rule the equal split rule and another rule that arises naturally from bargaining of the players

the investment behaviour of firms in an oligopolistic setting industrial organization theory has identified strategic investment in capacity as an important element in competition in oligopolistic markets in the paper we specify a model of oligopolistic investment behaviour and test it with panel data for 114 firms in 15 narrowly defined uk manufacturing industries in the 1970s and 1980s the industries are distinguished according to their market characteristics as fragmented dominant firm and dominant group sectors the results indicate behaviour which is noncooperative in fragmented sectors cooperative in dominant group sectors and competitive in dominant firm sectors

dynamic oligopoly with capacity adjustment costs abstract the literature on strategic investment emphasized the case of completely irreversible investment this paper considers an oligopoly model in which investment is reversible and capacity is subject to adjustment costs an n player linear quadratic differential game is analyzed existence and characterization results for perfect equilibrium feedback strategies are provided feedback strategies provide incentives for each player to invest strategically so as to preempt subsequent expansion by rivals a larger set of perfect equilibria is constructed by using memory dependent trigger strategies equilibria of this type are shown to support joint value maximization for some initial states and asymmetric steady states

optimal firm growth under the threat of entry the paper studies the incumbent entrant problem in a fully dynamic setting we find that under an open loop information structure the incumbent anticipates entry by overinvesting whereas in the markov perfect equilibrium the incumbent slightly underinvests in the period before the entry the entry cost level where entry accommodation passes into entry deterrence is lower in the markov perfect equilibrium further we find that the incumbent s capital stock level needed to deter entry is hump shaped as a function of the entry time whereas the corresponding entry cost where the entrant is indifferent between entry and non entry is u shaped

partial bandwagon effects and local interactions we consider partial bandwagon properties in the context of coordination games to capture the idea of weak network externalities we then study a local interactions model where agents play a coordination game following a noisy best reply process we show that globally pairwise risk dominant strategies are selected in arbitrary 3 3 coordination games but not necessarily in larger games a comparison with the global interactions benchmark shows that the nature of interactions might alter the long run results themselves and not only the speed of convergence we also illustrate that the simultaneous coexistence of conventions is possible for games with at least 5 strategies 2007 elsevier inc all rights reserved

on the formation of interaction networks in social coordination games there are many situations where two interacting individuals can benefit from coordinating their actions we examine the endogenous choice of partners in such social coordination games and the implications for resulting play we model the interaction pattern as a network where individuals periodically have the discretion to add or sever links to other players with such endogenous interaction patterns we see multiple stochastically stable states of play including some that involve play of equilibria in the coordination game that are neither efficient nor risk dominant thus the endogenous network structure not only has implications for the interaction pattern that emerges but it also has a significant impact on the play in the coordination game relative to what would arise if the same interaction network were exogenous

on the markovian efficiency of bertrand and cournot equilibria we characterize and compare closed loop feedback price and quantity strategies within a full fledged dynamic model of oligopolistic competition in which production requires exploitation of a renewable productive asset unlike previous papers on the strategic exploitation of productive assets we allow for imperfect product substitutability which enables us to deal with price competition we show that the traditional result that the bertrand equilibrium is more efficient than the cournot equilibrium does not necessarily hold in a markovian environment either in the short run or at the stationary equilibrium or using the discounted sum of welfare as a criterion for relative efficiency

decentralization and the coordination problem abstract this paper addresses the relationship between the degree of decentralization in a population and the probability of coordinating on an efficient outcome rather than the risk dominant outcome in a coordination game the model here extends the literature on evolutionary games by supposing that players interact in groups but that occasionally they may change groups the main innovation is the group changing assumption which allows players to vote with their feet in contrast to most of the recent literature e g kandori et al 1993 in which the risk dominant equilibrium is selected in the long run the model here predicts convergence to the efficient equilibrium if interaction is decentralized enough furthermore it is shown how the model can be applied to the problem of product standardization

oligopoly extraction of a common property natural resource the importance of the period of commitment in dynamic games the theory of noncooperative dynamic games has provided an extremely powerful framework for studying many of the classic questions in industrial organization for example questions about resource extraction advertising research and development investment in new capacity and barriers to entry where interactions over time among few firms are involved however an important methodological issue arises when economic competition over time is modeled as a dynamic game the issue is the appropriate formulation of the players strategy spaces

investment in tourism market a dynamic model of differentiated oligopoly we present a theoretical dynamic model in tourism economics assuming that the market for tourism is an oligopoly with differentiated products destinations can invest in order to improve their stock of physical natural or cultural resources tourism flows yield current revenues but they are usually detrimental for the stock of resources we find the solution of the dynamic model and in particular we find the open loop nash equilibrium of the game among destinations under alternative settings depending on whether the degree of differentiation among destinations is exogenous or endogenous in particular under the latter case an increase of the number of destinations leads to a higher degree of product differentiation in steady state

competition in a duopoly with sticky price and advertising abstract this paper develops a differential duopolistic game where price is sticky and firms can invest in market enlarging promotional activities which have a public good nature one finding indicates that advertising and not output as in fershtman and kamien econometrica 55 1987 1151 1164 is responsible for the higher stationary price found in the open loop equilibrium relative to the linear feedback one that is free riding is more intense when firms play linear markov feedback strategies however the collusive outcome can be approximated and opportunism eliminated if firms can engage in preplay negotiations where they select a nonlinear markov perfect strategy for output and advertising achieving the collusive outcome requires as in the folk theorem for infinitely repeated games the discount rate to be sufficiently small

the exploitation of fossil fuels under the threat of global warming and carbon taxes a dynamic game approach this paper considers efficient and monopolistic extraction of non renewable energy resources when the resource consumption leads simultaneously to a stock externality global warming the case of monopolistic supply leads to a dynamic game between cartelised producers and a consumers government for this game we compute linear markov perfect strategies that are characterized by preemption of the tax at the wellhead when compared with the open loop solution unfortunately the general asymmetric two state variable model does not allow for an explicit analytical solution therefore a simplified version with one state variable neglecting depreciation of the stock of the pollutant is studied and a numerical example is presented it turns out that the simplified and analytically solved framework provides a good approximation of the initial phase of the transient behaviour but not of the long run

on the long run distribution of capital in the ramsey model abstract we study issues related to the long run distribution of wealth in two variants of ramsey s model of optimal capital accumulation first we show that in the case where a government levies a progressive income tax there exist infinitely many stationary equilibria in which all households own positive capital stocks moreover it is demonstrated that non stationary equilibria can exhibit complicated dynamics then we discuss the case where households exercise market power on the capital market and we show that this may also lead to equilibria in which all households own positive amounts of capital journal of economic literature classification numbers e62 o41

capacity dynamics and endogenous asymmetries in firm size empirical evidence suggests that there are substantial and persistent differences in the sizes of firms in most industries we propose a dynamic model of capacity accumulation that is consistent with the observed facts the model highlights the mode of product market competition and the extent of investment reversibility as key determinants of the size distribution of firms in an industry in particular if firms compete in prices and the rate of depreciation is large then the industry moves toward an outcome with one dominant firm and one small firm industry dynamics in this case resemble a preemption race contrary to the usual intuition this preemption race becomes more brutal as investment becomes more reversible

the dynamics of lobbying a differential game this paper presents a dynamic model on lobbying the interactions between two competing lobbies who attempt to influence regulations and legislation are modelled as a differential game we consider for this game first a time consistent and then a subgame perfect equilibrium in linear markov strategies the subgame perfect equilibrium lowers considerably lobbying activity and expenses this provides a partial explanation of the puzzle that rent seeking expenses are often small compared with the prize sought