Measuring Strategic Uncertainty in Coordination Games

Lecture on the first SFB/TR 15 meeting, Gummersbach, July, 18 - 20, 2004This paper explores predictability of behavior in coordination games with multiple equilibria. In a laboratory experiment we measure subjects' certainty equivalents for three coordination games and one lottery. Attitudes towards strategic uncertainty in coordination games are related to risk aversion, experience seeking, gender and age. From the distribution of certainty equivalents among participating students we estimate probabilities for successful coordination in a wide range of coordination games. For many games success of coordination is predictable with a reasonable error rate. The best response of a risk neutral player is close to the global-game solution. Comparing choices in coordination games with revealed risk aversion, we estimate subjective probabilities for successful coordination. In games with a low coordination requirement, most subjects underestimate the probability of success. In games with a high coordination requirement, most subjects overestimate this probability. Data indicate that subjects have probabilistic beliefs about success or failure of coordination rather than beliefs about individual behavior of other players.

When and Why? A Critical Survey on Coordination Failure in the Laboratory

Coordination games with Pareto-ranked equilibria have attracted major theoretical attention over the past two decades. Two early path-breaking sets of experimental studies were widely interpreted as suggesting that coordination failure is a common phenomenon in the laboratory. We identify the major determinants that seem to affect the incidence, and/or emergence, of coordination failure in the lab and review critically the existing experimental studies on coordination games with Pareto-ranked equilibria since that early evidence emerged. We conclude that there are many ways to engineer coordination successes.coordination games, Pareto-ranked equilibria, payoff-asymmetric equilibria, staghunt games, optimization incentives, robustness, coordination, coordination failure

Coordination Games with Quantum Information

The paper discusses coordination games with remote players that have access to an entangled quantum state. It shows that the entangled state cannot be used by players for communicating information, but that in certain games it can be used for improving coordination of actions. A necessary condition is provided that helps to determine when an entangled quantum state can be useful for improving coordination.quantum games, coordination games, quantum entanglement, communication

Measuring Strategic Uncertainty in Coordination Games

Lecture on the first SFB/TR 15 meeting, Gummersbach, July, 18 - 20, 2004This paper explores predictability of behavior in coordination games with multiple equilibria. In a laboratory experiment we measure subjects' certainty equivalents for three coordination games and one lottery. Attitudes towards strategic uncertainty in coordination games are related to risk aversion, experience seeking, gender and age. From the distribution of certainty equivalents among participating students we estimate probabilities for successful coordination in a wide range of coordination games. For many games success of coordination is predictable with a reasonable error rate. The best response of a risk neutral player is close to the global-game solution. Comparing choices in coordination games with revealed risk aversion, we estimate subjective probabilities for successful coordination. In games with a low coordination requirement, most subjects underestimate the probability of success. In games with a high coordination requirement, most subjects overestimate this probability. Data indicate that subjects have probabilistic beliefs about success or failure of coordination rather than beliefs about individual behavior of other players

Informational Smallness and Privae Momnitoring in Repeated Games, Second Version

We consider repeated games with private monitoring that are .close. to repeated games with public/perfect monitoring. A private monitoring information structure is close to a public monitoring information structure when private signals can generate approximately the same distribution of the public signal once they are aggregated into a public signal by some public coordination device. A player.s informational size associated with the public coordination device is the key to inducing truth-telling in nearby private monitoring games when communication is possible. A player is informationally small given a public coordination device if she believes that her signal is likely to have a small impact on the public signal generated by the public coordinating device. We show that a uniformly strict equilibrium with public monitoring is robust in a certain sense: it remains an equilibrium in nearby private monitoring repeated games when the associated public coordination device, which makes private monitoring close to public monitoring, keeps every player informationally small at the same time. We also prove a new folk theorem for repeated games with private monitoring and communication by exploiting the connection between public monitoring games and private monitoring games via public coordination devices.Communication, Folk theorem, Informational size, Perfect monitoring, Private monitoring, Public monitoring, Repeated games, Robustness

Evolution of Coordination in Social Networks: A Numerical Study

Coordination games are important to explain efficient and desirable social behavior. Here we study these games by extensive numerical simulation on networked social structures using an evolutionary approach. We show that local network effects may promote selection of efficient equilibria in both pure and general coordination games and may explain social polarization. These results are put into perspective with respect to known theoretical results. The main insight we obtain is that clustering, and especially community structure in social networks has a positive role in promoting socially efficient outcomes.Comment: preprint submitted to IJMP

Game Harmony: A Short Note

Strategic uncertainty in game theory may have two different general sources, either alone or in combination: uncertainty because of the existence of a coordination problem, and uncertainty because of a conflict between one own and the other n players' interests. Game harmony is conceived as a generic game property that describes how harmonious (non-conflictual) or disharmonious (conflictual) the interests of the n players are, as embodied in the game payoffs. Pure coordination games are examples of games with maximal game harmony; zero sum games are examples of games with very low game harmony. This note briefly describes attempts to measure game harmony simply as a real-valued number

Macroeconomic Stabilization Policies in the EMU: Spillovers, Asymmetries, and Institutions

This paper studies the institutional design of the coordination of macroeconomic stabilization policies within a monetary union in the framework of linear quadratic differential games. A central role in the analysis plays the partitioned game approach of the endogenous coalition formation literature. The specific policy recommendations in the EMU context depend on the particular characteristics of the shocks and the economic structure. In the case of a common shock, fiscal coordination or full policy coordination is desirable. When asymmetric shocks are considered, fiscal coordination improves the performance but full policy coordination doesn’t produce further gains in policymakers’ welfare.macroeconomic stabilization, EMU, coalition formation, linear quadratic differential games

Game Harmony as a Predictor of Cooperation in 2 x 2 Games

This paper presents an experimental test of the relationship between game harmony and cooperation in 2 x 2 games. Game harmony measures describe how harmonious (non-conflictual) or disharmonious (conflictual) the interests of players are, as embodied in the payoffs: coordination games and constant-sum games are examples of games of perfect harmony and disharmony, respectively; most games are somewhere in the middle. Correlation coefficients between measured harmony and cooperation rates were above 0.8 in an experiment with games such as the Prisoner`s Dilemma, the Stag-Hunt, a coordination game and three trust games, and above 0.55 in an experiment with random games.Game harmony, Cooperation, 2 x 2 games, Trust games, Social dilemmas

When envy helps explain coordination

This paper identifies a class of symmetric coordination games in which the presence of envious people helps players to coordinate on a particular strict Nash equilibrium. In these games, the selected equilibrium is always risk-dominant. We also find that envious preferences are evolutionary stable when they lead to Pareto-efficiency.Envy Coordination games Risk-dominance Evolutionary stability