Electoral competition with privately-informed candidates

This paper formulates and analyzes a general model of elections in which candidates receive private signals about voters' preferences prior to committing to political platforms. We fully characterize the unique pure-strategy equilibrium: After receiving her signal, each candidate locates at the median of the distribution of the median voter's location, conditional on the other candidate receiving the same signal. Sufficient conditions for the existence of pure strategy equilibrium are provided. Though the electoral game exhibits discontinuous payoffs for the candidates, we prove that mixed strategy equilibria exist generally, that equilibrium expected payoffs are continuous in the parameters of the model, and that mixed strategy equilibria are upper hemicontinuous. This allows us to study the robustness of the median voter theorem to private information: Pure strategy equilibria may fail to exist in models “close” to the Downsian model, but mixed strategy equilibria must, and they will be “close” to the Downsian equilibrium.     

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.     

Credible communication in dynastic government

This paper studies information disclosure in a model of dynastic government. When information about past policy choices comes exclusively from the reports of previous administrations, each administration has an incentive to choose its (suboptimal) one-shot expenditure policy, and then misrepresent its choice to its successor. Consequently, it has been suggested that “horizontal accountability,” i.e., a system of governance where auditing functions lie outside the executive branch, can ensure credible disclosure of a government's activities. This paper suggests a cautious approach to that view.The baseline model examines the reporting incentives of an external auditor who can independently verify the information each period. Even with auditing, credible disclosure is shown to be problematic. Various extensions to this baseline model are examined. In one extension, “liberal” (i.e., those prefering larger government expenditures) and “conservative” (those prefering smaller expenditures) regimes and auditors evolve over time. It is shown that “conservative” (“liberal”) auditors are not credible when the current regime is also “conservative” (“liberal”). Moreover, because information transmission stops when the auditor's and the regime's biases coincide, effective deterrents even in the “good” periods (when the auditor's and the administration's biases differ) are difficult to construct. In all periods the equilibrium requirement of auditor neutrality constrains the dynamic incentives for efficient policy choices. These constraints are shown to bind away from optimal policies in standard constructions of equilibrium. Various ways in which auditing protocols can overcome these problems are discussed.     

Intragroup competition in public good games: The role of relative performance incentives and risk attitudes

We analyze a public good game (PGG) with intragroup competition in which, generally but not always, the dominant strategy is to not contribute; therefore, free riding is the unique Nash equilibrium, not achieving Pareto efficiency. We propose a PGG setup where subjects' contributions are rewarded with different individual returns following a rank‐order voluntary contribution mechanism. It is found that the resulting competition for a better return significantly increases contributions. This effect is sensitive to the salience of return differences rewarding higher contributions. Furthermore, the positive effect of return differences on contribution levels depends on an individual's return‐to‐risk sensitivity as elicited through an independent risk elicitation task.     

Reciprocity Game

This paper shows that reciprocity comes from the desire to cooperate in finitely repeated prisoner's dilemma game. Before playing the finitely repeated prisoner's dilemma game, players choose the reciprocity level and commit to it, and the reciprocity level is public information. There are T equilibria if the prisoner's dilemma game is repeated for T periods, and each equilibrium is associated with different levels of cooperation. Further, if players choose their reciprocity levels sequentially, then the most cooperative equilibrium will be the unique equilibrium. However, reciprocity does not matter for the one‐period game and the infinitely repeated game.     

IMPLEMENTATION CYCLES,INVESTMENT, AND GROWTH*

We develop a model of “intrinsic” cycles, driven by the decentralized behavior of entrepreneurs and firms making continuous, divisible improvements in their productivity. We show that when the introduction of productivity improvements is endogenous, implementation cycles arise even in the presence of reversible investment and consumption smoothing. The implied cyclical equilibrium is unique within its class and shares several features in common with actual business cycles. In particular, its predictions are qualitatively consistent with the joint behavior of the investment rate and Tobin's Q during U.S. recessions.     

Evolutionary Stability in the Finitely Repeated Prisoner 's Dilemma Game

The dynamic evolutionary stability of mutual defection is proven for the repeated prisoner 's dilemma game where payoffs are cumulative and the number of repetitions is known. This agrees with the classical result that the only Nash equilibrium outcome is to defect at all stages of this repeated game. Moreover, it is shown that, for any initial polymorphic population, the evolutionary dynamic converges to a unique Nash equilibrium strategy that depends on the original polymorphism. Both these results confirm earlier conjectures concerning the application of evolutionary game theory to the repeated prisoner 's dilemma.Journal of Economic LiteratureClassification Numbers: C70, C72.     

EXTREMIST PLATFORMS: POLITICAL CONSEQUENCES OF PROFIT-SEEKING MEDIA

We analyze how information about candidate quality affects the choice of electoral platforms made by an office-motivated political challenger. The incumbent is of known quality and located at the ideal policy of the voter. The voter cares for both policy and the candidates' quality and can learn about the challenger's quality by buying information. A high-quality challenger then has an incentive to signal her quality by choosing a policy that induces the voter to buy information. We first study the benchmark case in which the information is supplied exogenously, and its quality is independent of the challenger's platform; this yields multiple equilibria and indeterminacy of equilibrium platforms. By contrast, when the information is supplied by a profit-maximizing media outlet, its quality depends on the challenger's platform and we obtain a unique equilibrium platform. In particular, when the incumbent's quality is relatively low, the media coverage rises and the challenger's platform diverges further from the voter's ideal policy as the voter's preference for quality increases.     

Equilibrium play and best response to (stated) beliefs in normal form games

We report experimental results on a series of ten one-shot two-person 3×3 normal form games with unique equilibrium in pure strategies played by non-economists. In contrast to previous experiments in which game theory predictions fail dramatically, a majority of actions taken coincided with the equilibrium prediction (70.2%) and were best-responses to subjects' stated beliefs (67.2%). In constant-sum games, 78% of actions taken were predicted by the equilibrium model, outperforming simple K-level reasoning models. We discuss how non-trivial game characteristics related to risk aversion, efficiency concerns and social preferences may affect the predictive value of different models in simple normal form games.     

Two-sided competition with vertical differentiation

This paper studies duopoly in which two-sided platforms compete in differentiated products in a two-sided market. Direct competition on both sides leads to results that depart from much of the current literature. Under some conditions the unique equilibrium in pure strategies can be computed. It features discounts on one side and muted differentiation as the cross-market externality intensifies competition. Less standard, that equilibrium fails to exist when the externality is too powerful (that side becomes too lucrative). A mixed-strategy equilibrium always exists and is characterized. These results are robust to variations in the extensive form. The model may find applications in the media, internet trading platforms, search engine competition, social media or even health insurance (HMO/PPO).     

Tournament incentives and match outcomes in women's professional tennis

Our research examines the effect of prize money differentials in women's professional tennis tournaments on the probability that the favoured player wins the match. This study adds to the existing literature on tournament theory through its focus on Rosen's (1986) elimination-style, match play tournament model. We estimate a standard probit model using a unique data set containing detailed information on prize money, player-specific characteristics, and match play outcomes for all tournaments played during the 2004 tour sponsored by the Women's Tennis Association (WTA). Our results support predictions by Rosen's tournament model. Larger prize money differentials have a positive, statistically significant effect on the favoured player's probability of winning the match. In addition, the number of stages remaining has a significant, negative effect on winning, consistent with tournament theory predictions associated with the number of contestants in a tournament.     

Majority Rule in a Stochastic Model of Bargaining

In this paper we consider multilateral stochastic bargaining models with general agreement rules. For n-player games where in each period a player is randomly selected to allocate a stochastic level of surplus and q?n players have to agree on a proposal to induce its acceptance, we characterize the set of stationary subgame perfect equilibrium payoffs and establish their existence. We show that for agreement rules other than the unanimity rule, the equilibrium payoffs need not be unique. Furthermore, even when the equilibrium is unique, it need not be efficient. Journal of Economic Literature Classification Numbers: C73, C78, D70.     

Cyclic Games: An Introduction and Some Examples

We introduce a model of a cyclic game. Designed to take advantage of the recurring nature of certain economic and social situations, a cyclic game differs from an extensive form game in that a cyclic game does not necessarily have an end. The same situations, although with different players, may be repeated infinitely often. We provide an example showing that, even though a cyclic game has, in a sense, perfect information, it may not have an equilibrium in pure strategies. We demonstrate existence of equilibrium and illustrate the application of our model to an oligopolistic industry. Journal of Economic Literature Classification Numbers: C72, C73, D43.     

Information gatekeepers: theory and experimental evidence

We consider a model where two adversaries can spend resources in acquiring public information about the unknown state of the world in order to influence the choice of a decision maker. We characterize the sampling strategies of the adversaries in the equilibrium of the game. We show that as the cost of information acquisition for one adversary increases, that person collects less evidence whereas the other adversary collects more evidence. We then test the results in a controlled laboratory setting. The behavior of subjects is close to the theoretical predictions. Mistakes are relatively infrequent (15%). They occur in both directions, with a higher rate of over-sampling (39%) than under-sampling (8%). The main difference with the theory is the smooth decline in sampling around the theoretical equilibrium. Comparative statics are also consistent with the theory, with adversaries sampling more when their own cost is low and when the other adversary??s cost is high. Finally, there is little evidence of learning over the 40 matches of the experiment.     

Bargaining and network structure: An experiment

We consider bargaining in a bipartite network of buyers and sellers, who can only trade with the limited number of people with whom they are connected. We perform an experimental test of a graph-theoretic model that yields unique predictions about equilibrium prices for the networks in our sessions. The results diverge sharply depending on how a connection is made between two separate simple networks, typically conforming to the theoretical directional predictions. Payoffs can be systematically affected even for agents who are not connected by the new link, and we find evidence of a form of social learning.     

Strategic Buyers and Privately Observed Prices

A model of finitely repeated price competition between two sellers with differentiated goods and a large buyer is analyzed. The set of pure strategy sequential equilibria is investigated under public and private monitoring. With private monitoring, i.e., when prices are not observable to the competing sellers, all sales are made by the better seller and the set of repeated game equilibrium payoffs coincides with the stage game subgame perfect equilibrium payoffs. This is in sharp contrast to the game with perfect monitoring where the folk theorem obtains. Journal of Economic Literature Classification Numbers: C72, D43.     

AN EXPERIMENTAL STUDY OF UNCERTAINTY IN COORDINATION GAMES

Global games and Poisson games have been proposed to address equilibrium indeterminacy in Common Knowledge Coordination games. The present study investigates in a controlled setup, using as controls Common Knowledge games, whether idiosyncratic uncertainty about economic fundamentals (Global games) or uncertainty about the number of actual players (Poisson games) may influence subjects' behavior. We find that uncertainty about the number of actual players has more influence on subjects' behavior than idiosyncratic uncertainty about economic fundamentals. Furthermore, subjects' behavior under Poisson population‐size uncertainty is closer to the respective theoretical prediction than subjects' behavior under idiosyncratic uncertainty about economic fundamentals.     

Bounded Rationality in Principal‐Agent Relationships

We conducted six treatments of a standard moral hazard experiment with hidden action. The behavior in all treatments and periods was inconsistent with established agency theory. In the early periods, behavior differed significantly between treatments. This difference largely vanished in the final periods. We used logit agent quantal response equilibrium (LAQRE) as a device to grasp boundedly rational behavior and found the following: (1) LAQRE predictions are much closer to subjects' behavior in the laboratory; (2) LAQRE probabilities and experimental behavior show remarkably similar patterns; and (3) including social preferences in LAQRE does not better explain the experimental data; (4) LAQRE cannot explain the contract offers of some players who seem to choose some focal contract parameters.     

Uniqueness in symmetric first-price auctions with affiliation

The first-price auction has a unique monotone pure strategy equilibrium when there are n symmetric risk-averse bidders having affiliated types and interdependent values.     

A MARKET WITH FRICTIONS IN THE MATCHING PROCESS: AN EXPERIMENTAL STUDY*

We construct a laboratory market in which there is a friction in the matching between buyers and sellers. Sellers simultaneously post prices and then buyers simultaneously choose a seller. If more than one buyer chooses the same seller, the seller's single unit is randomly sold to one of them. Our results show a broad consistency with theoretical predictions, although price dispersion exists and is slow to decay. Prices also exceed the equilibrium level when there are only two sellers, and buyers' purchase probabilities are insufficiently responsive to price differences when there are two sellers.