Competitive behavior in market games: Evidence and theory

We explore whether competitive outcomes arise in an experimental implementation of a market game, introduced by Shubik (1973) [21]. Market games obtain Pareto inferior (strict) Nash equilibria, in which some or possibly all markets are closed. We find that subjects do not coordinate on autarkic Nash equilibria, but favor more efficient Nash equilibria in which all markets are open. As the number of subjects participating in the market game increases, the Nash equilibrium they achieve approximates the associated competitive equilibrium of the underlying economy. Motivated by these findings, we provide a theoretical argument for why evolutionary forces can lead to competitive outcomes in market games.     

Cooperation and Institution in Games

Based on recent developments in non‐cooperative coalitional bargaining theory, I review game theoretical analyses of cooperation and institution. First, I present basic results of the random‐proposer model and apply them to the problem of involuntary unemployment in a labour market. I discuss extensions to cooperative games with externalities and incomplete information. Next, I consider the enforceability of an agreement as an institutional foundation of cooperation. I re‐examine the contractarian approach to the problem of cooperation from the viewpoint that individuals may voluntarily create an enforcement institution.     

Electoral goals and center-state transfers: A theoretical model and empirical evidence from India

We construct a model of redistributive politics where the central government is opportunistic and uses its discretion to make transfers to state governments on the basis of political considerations. These considerations are the alignment between the incumbent parties at the central and state levels and whether a state is a swing state or not. A testable prediction from the model is that a state that is both swing and aligned with the central government is especially likely to receive higher transfers. We test this prediction using Indian data for 14 states from 1974–75 to 1996–97. We find that a state which is both aligned and swing in the last state election is estimated to receive 16% higher transfers than a state which is unaligned and non-swing.     

Democracy,dictatorship, and transformation: A proposal for a constitution-guided systematic change in formerly Soviet republics

A system transformation contains complicated social dilemmas and special-interest problems. Thus it is frequently suggested that democratic decisionmaking is inappropriate for introducing a market economy in the former socialist countries. In this paper I argue that this view rests on a nirvana approach, because it neglects the dynamics of authoritarian governments. It is shown that dictatorships tend to serve even narrower special interests than democracies and are therefore usually less likely to pursue a consistent transformation policy. However, a dictatorship could, under certain cultural and social conditions, have some advantages over democracies. But those conditions are barely present in the formerly socialist countries. Moreover, a dictatorship can by its very nature not be committed and cannot even commit itself to a certain public policy. Hence, there is only one instrument to mitigate social dilemmas in transformation countries: a set of constitutional rules. Some basic properties of a constitutional approach of system transformation are introduced in the last section of the paper.     

Informed trading and the ‘leakage’ of information

This paper examines the effect of ‘leakage’ of information, private information becoming available to uninformed traders at a later date, on information acquisition and revelation. Using a Shapley-Shubik market game framework it is shown that (a) if information acquisition by the informed traders is costless, this leads to faster revelation of information; (b) if information acquisition is costly, there may be no acquisition of information; (c) information leakage leads to a fall in value of information but does not affect the incentive for informed traders to sell the information.     

Positioning and negotiations: The case of pharmaceutical pricing

We study a positioning game prior to negotiations where each party invests into influential activities in order to raise voter support for their preferred bargaining outcome. The case chosen for our analysis is a bilateral monopoly where a purchaser meets a pharmaceutical firm and where the two negotiate on the price of a new and innovative medicine. We identify factors that influence on the negotiated price such as treatment effects of the new and the existing drug, production costs of the new drug, the price of the existing drug, the marginal cost of public funds and patient group size. Furthermore, it is shown that the negotiated price, depending on the characteristics of a political cost function with regard to the influential activities, is influenced by the order of moves taken by the parties. Regardless of the strategic interrelationships between the two parties, likely positioning games to be played are those where one of the two negotiating parties acts as a leader while the rival acts as a follower.     

The collective action problem: Within-group cooperation and between-group competition in a repeated rent-seeking game

This paper analyzes the ability of group members to cooperate in rent-seeking activities in a context of between-group competition. For this purpose, we develop an infinitely repeated rent-seeking game between two groups of different size. We first investigate Nash reversion strategies to support cooperative behavior in both groups, before analyzing double-edge trigger strategies which support cooperation in one group only. These last strategies have the property that cheating on the agreement in the cooperative group is followed by non-cooperation in this group and cooperation in the rival group. The main conclusion is that the set of parameters for which cooperation can be sustained within the larger group as a subgame perfect outcome is as large as that for which cooperation can be sustained in the smaller group. Hence, in contrast to Olson?s (1965) celebrated thesis, but in accordance with many informal and formal observations, larger groups can be as effective as smaller groups in furthering their interests.     

When mandatory disclosure hurts: Expert advice and conflicting interests

We study the quality of advice that an informed and biased expert gives to an uninformed decision maker. We compare two scenarios: mandatory disclosure of the bias and nondisclosure, where information about the bias can only be revealed through cheap-talk. We find that in many scenarios nondisclosure allows for higher welfare for both parties. Hiding the bias allows for more precise communication for the more biased type and, if different types are biased in different directions, may allow for the same for the less biased type. We identify contexts where equilibrium revelation allows but mandatory disclosure prevents meaningful communication.     

Bargaining and markets: complexity and the competitive outcome

Rubinstein and Wolinsky (Rev. Econ. Stud. 57 (1990) 63-78) consider a simple decentralised market game in which agents meet randomly or voluntarily and bargain over the terms of trade. They show that any individually rational price can be sustained as a sequential equilibrium even though the model has a unique competitive outcome. Here, I consider Rubinstein and Wolinsky's model and show that if complexity costs of implementing strategies enter players’ preferences, together with the standard payoff in the game, then every equilibrium is stationary/Markov and induces the unique competitive price. Thus, I demonstrate that aversion to complexity may provide a justification for the competitive outcome.     

Variational convergence: Approximation and existence of equilibria in discontinuous games

We introduce a notion of variational convergence for sequences of games and we show that the Nash equilibrium map is upper semi-continuous with respect to variationally converging sequences. We then show that for a game G with discontinuous payoff, some of the most important existence results of Dasgupta and Maskin, Simon, and Reny are based on constructing approximating sequences of games that variationally converge to G. In fact, this notion of convergence will help simplify these results and make their proofs more transparent. Finally, we use our notion of convergence to establish the existence of a Nash equilibrium for Bertrand-Edgeworth games with very general forms of tie-breaking and residual demand rules.     

Behavioral spillovers and cognitive load in multiple games: An experimental study

We present evidence from laboratory experiments of behavioral spillovers and cognitive load that spread across strategic contexts. In the experiments, subjects play two distinct games simultaneously with different opponents. We find that the strategies chosen and the efficiency of outcomes in one game depends on the other game that the subject plays, and that play is altered in predictable directions. We develop a measure of behavioral variation in a normal form game, outcome entropy, and find that prevalent strategies in games with low outcome entropy are more likely to be used in the games with high outcome entropy, but not vice versa. Taken together, these findings suggest that people do not treat strategic situations in isolation, but may instead develop heuristics that they apply across games.     

Unobserved heterogeneity and equilibrium: an experimental study of Bayesian and adaptive learning in normal form games

We describe an experiment based on a simple two-person game designed so that different learning models make different predictions. Econometric analysis of the experimental data reveals clear heterogeneity in the subjects’ learning behavior. But the subjects follow only a few decision rules for basing their play on their information, and these rules have simple cognitive interpretations. There is a unique equilibrium in pure strategies, and many equilibria in mixed strategies. We find that the only equilibrium consistent with the data is one of the mixed strategy equilibria. This equilibrium is shown, surprisingly, to be consistent with Jordan's Bayesian model.     

Hope springs eternal: learning and the stability of cooperation in short horizon repeated games

This paper considers learning rates in finitely repeated prisoners’ dilemmas. If players think their opponents might be relatively cooperative (e.g., tit-for-tat or grim types), they will cooperate in finitely repeated prisoners’ dilemmas (see Kreps et al., J. Econom. Theory 27 (1982) 245). However, if there are actually no cooperative types, players will eventually learn this and cooperation will break down. This paper shows that this learning is extremely slow, so it will take an extremely long time for cooperation to break down.Thus, suppose the world is either “good” or “bad.” The probability of a grim type is δ>0 if the world is good, and zero if the world is bad. Successive generations pair up to play finitely repeated prisoners’ dilemmas. Players observe play in previous generations and use Bayes’ rule to update their prior, π, that the world is good. We show that, if the world is really bad, then π falls per generation on average. Thus, if δ is small, there is less cooperation if the world is good, but cooperation may become more stable. For a representative 19 period repeated prisoners’ dilemma, beliefs fall one percentage point on average after a thousand generations.To derive these learning rates, we must refine existing results on the sensitivity of repeated games to Kreps et al. (1982) type perturbations. Specifically, we show cooperation is possible in perturbed prisoners’ dilemmas repeated O(log(1/δ)) times. This improves significantly on the O(1/δ) results in previous work. The paper thus provides two new reasons why cooperation tends to be stable, even in short horizon repeated games.     

Star-shapedness of Richter-Aumann integral on a measure space with atoms: theory and economic applications

This paper provides sufficient (as well as necessary) conditions for the integral of a correspondence defined on a measure space with atoms to exhibit star-shaped values. This result is used to analyze the existence of a Nash equilibrium in games with a measure space of agents with atoms and of a competitive equilibrium in economies with mixed markets. In either case it is shown that an exact equilibrium exists whenever atoms are “small enough”.     

Stationary monetary equilibria with strictly increasing value functions and non-discrete money holdings distributions: An indeterminacy result

In this paper, we present a search model with divisible money in which there exists a continuum of monetary equilibria with strictly increasing continuous value functions and with non-discrete money holdings distributions.     

Supply function equilibria: Step functions and continuous representations

In most electricity markets generators must submit step-function offers to a uniform price auction. These markets are often modelled as simpler pure-strategy Supply Function Equilibria (SFE) with continuous supply functions. Critics argue that the discreteness and discontinuity of the required steps drastically change Nash equilibria, invalidating predictions of the SFE model. We prove that there are sufficient conditions, offered quantities can be continuously varied, offered prices are selected from a finite set, and the density of the additive demand shock is not too steep, where the resulting stepped SFE converges to the continuous SFE as the number of steps increases, reconciling the apparently very disparate approaches to modelling electricity markets.     

The influence of group size on distributional fairness under voting by veto

Voting by Veto [VBV], developed by Dennis C. Mueller, is a two-stage voting mechanism for committee decision making. In the first stage, every member of the committee makes a proposal. The proposals are joined with the current status quo (or another fallback option). For the second stage, a random mechanism determines the order of voting and the committee members sequentially eliminate one alternative each. After every committee member has exercised her veto, a single winning alternative remains. Game theory predicts that the equality of the resulting distribution under VBV varies with group size. Hence, decisions in two-member groups should result in highly unequal distributions of benefits. With increasing group size, however, VBV should generate more equally distributed outcomes. We examine the effect of group size under VBV in a series of laboratory experiments where groups with a varying number of members play a ‘divide the dollar game’. Our results confirm that larger groups choose more equal distributions than smaller groups. However, we also find deviations from the model's predictions. Some committees in our experiment do not select Pareto-optimal alternatives. An exploratory analysis of possible explanations suggests that individual behavior is most likely motivated by a combination of material self-interest and social preferences such as reciprocity and fairness.     

Imitation and the evolution of Walrasian behavior: Theoretically fragile but behaviorally robust

A well-known result by Vega-Redondo (1997) [18] implies that in symmetric Cournot oligopolies, imitation leads to the Walrasian outcome. We show that this result is not robust to the slightest asymmetry in costs, since every outcome where agents choose identical actions will be played some fraction of the time in the long run. We then conduct experiments to check this fragility. We obtain that, contrary to the theoretical prediction, the Walrasian outcome is a good predictor of market outcomes. Finally, we suggest a new theory based on a mix of imitation and other learning processes that explains subjects' behavior fairly well.     

Disentangling liberalization and privatization policies: Is there a political trade-off?

We empirically investigate the political determinants of liberalization and privatization policies in six network industries of 30 OECD countries (1975–2007). We unbundle liberalization and privatization reforms and study their simultaneous determination in a two-equation model. Unlike previous studies, we account for cross-effects between the two pro-market measures. Our findings unveil that both right-wing and left-wing governments implement liberalizations and privatizations, showing a common trend under the so-called neo-liberalism wave. However, although the privatization rate is higher than liberalization in right-wing environments, the opposite occurs under left-wing governments. We argue that ideological cleavages still affect pro-market reforms, particularly the combination of privatization and liberalization policies. We conclude that different deregulation patterns should be expected under governments characterized by different political ideologies. Our results shed new light on the literature investigating the political-economic rationale underpinning pro-market choices.     

Low-wage import competition and populist backlash: The case of Italy

This paper studies empirically the role of trade globalization in shifting the electoral base towards populism. We proxy the trade shock with swiftly rising import competition from China and compare voting patterns at the national parliamentary elections from 1992 to 2013 in about 8000 Italian municipalities differently exposed to the trade shock. We instrument import competition from China with Chinese export flows to other high-income countries and estimate the model in first differences. Our results indicate that trade globalization increases support for populist parties, as well as invalid votes and abstentionism. To rationalize these findings, we offer evidence that import competition worsens local labor market conditions – higher unemployment, lower income and durable consumption – and increases inequality. Finally, we point out that local public expenditure may play a role in mitigating the political consequences of the trade shock, arguably because it alleviates economic distress.