We investigate how information about the preferences of others affects the persistence of ‘bad’ social norms. One view is that bad norms thrive even when people are informed of the preferences of others, since the bad norm is an equilibrium of a coordination game. The other view is based on pluralistic ignorance, in which uncertainty about others’ preferences is crucial. In an experiment, we find clear support for the pluralistic ignorance perspective . In addition, the strength of social interactions is important for a bad norm to persist. These findings help in understanding the causes of such bad norms, and in designing interventions to change them.

This paper reports an experiment designed to detect the influence of strategic uncertainty on behavior in order statistic coordination games, which arise when a player's best response is an order statistic of the cohort's action combination. Unlike previous experiments using order statistic coordination games, the new experiment holds the payoff function constant and only changes cohort size and order statistic.

We study a setting where individuals prefer to coordinate with others but they differ on their preferred action. Our interest is in understanding the role of link formation with others in shaping behavior. So we consider the situation in which interactions are exogenous and a situation where individuals choose links that determine the interactions. Theory is permissive in both settings: conformity (on either of the actions) and diversity (with different groups choosing their preferred actions) are both sustainable in equilibrium. We conduct an experiment to understand how link formation affects equilibrium selection. Our experiment reveals the powerful effect of linking on equilibrium selection: with an exogenous complete network, subjects choose to conform on the majority’s preferred action. By contrast, with endogenous linking—irrespective of the costs of linking—subjects always opt for diversity of actions.

We perform an experiment on a pure coordination game with uncertainty about the payoffs. Our game is closely related to models that have been used in many macroeconomic and financial applications to solve problems of equilibrium indeterminacy. In our experiment, each subject receives a noisy signal about the true payoffs. This game (inspired by the “global” games of Carlsson and van Damme, Econometrica, 61, 989-1018, 1993) has a unique strategy profile that survives the iterative deletion of strictly dominated strategies (thus a unique Nash equilibrium). The equilibrium outcome coincides, on average, with the risk-dominant equilibrium outcome of the underlying coordination game. In the baseline game, the behavior of the subjects converges to the theoretical prediction after enough experience has been gained. The data (and the comments) suggest that this behavior can be explained by learning. To test this hypothesis, we use a different game with incomplete information, related to a complete information game where learning and prior experiments suggest a different behavior. Indeed, in the second treatment, the behavior did not converge to equilibrium within 50 periods in some of the sessions. We also run both games under complete information. The results are sufficiently similar between complete and incomplete information to suggest that risk-dominance is also an important part of the explanation.

We report on an experiment examining behavior and equilibrium selection in two similar, infinitely repeated games, Stag Hunt and Prisoner’s Dilemma under anonymous random matching. We are interested in the role that historical precedents may play for equilibrium selection between these two repeated games. We find that a precedent for efficient play in the repeated Stag Hunt game does not carry over to the repeated Prisoner’s Dilemma game despite the possibility that efficient play can be sustained as an equilibrium of the indefinitely repeated game. Similarly, a precedent for inefficient play in the repeated Prisoner’s Dilemma game does not extend to the repeated Stag Hunt game. We conclude that equilibrium selection between similar repeated games may have less to do with historical precedents and might instead depend more on strategic considerations associated with the different payoffs of these similar repeated games.

When public goods can only be provided when donations cross a minimum threshold, this creates an advantage in that Pareto Efficient outcomes can be Nash Equilibria. Despite this, experiments have shown that groups struggle to coordinate on one of the many efficient equilibria. We apply a mechanism used successfully in continuous public goods games, the Hired Gun Mechanism (Andreoni and Gee in J. Public Econ. 96(11–12):1036–1046, 2012), to see if it can successfully get subjects across the threshold. When we use the mechanism to eliminate only inefficient equilibria, without addressing coordination, there is a modest but statistically insignificant improvement with the mechanism. However, when we hone the mechanism to eliminate all but one of the provision-point equilibria, thereby addressing the coordination issue, the mechanism moves all subjects to the desired efficient outcome almost immediately. In fact, after only one round using the hired gun mechanism, all subject are coordinating on the chosen equilibrium. The mechanism can be applied in settings where a group (1) has a plan for public good provision, (2) can measure contributions, (3) can fine members and (4) has an agreed upon standard for expected contributions. In these settings simple punishments, when focused on solving coordination as well as free riding, can greatly improve efficiency.

There is mixed evidence on whether subjects coordinate on the efficient equilibrium in experimental stag hunt games under complete information. A design that generates an anomalously high level of coordination, Rankin et al. (Games Econo Behav 32(2):315–337, 2000), varies payoffs each period in repeated play rather than holding them constant. These payoff “perturbations” are eerily similar to those used to motivate the theory of global games, except the theory operates under incomplete information. Interestingly, that equilibrium selection concept is known to coincide with risk dominance, rather than payoff dominance. Thus, in theory, a small change in experimental design should produce a different equilibrium outcome. We examine this prediction in two treatments. In one, we use public signals to match Rankin et al. (2000)’s design; in the other, we use private signals to match the canonical example of global games theory. We find little difference between treatments, in both cases, subject play approaches payoff dominance. Our literature review reveals this result may have more to do with the idiosyncrasies of our complete information framework than the superiority of payoff dominance as an equilibrium selection principle.

Does monitoring past conduct facilitate intertemporal cooperation? We designed an experiment characterized by strategic uncertainty and multiple equilibria where coordinating on the efficient outcome is a challenge. Participants, interacting anonymously in a group, could pay a cost either to obtain information about their counterparts, or to create a freely available public record of individual conduct. Both monitoring institutions were actively employed. However, groups were unable to attain higher levels of cooperation compared to a treatment without monitoring. Information about past conduct alone thus appears to be ineffective in overcoming coordination challenges.

We present experimental evidence on the interplay between strategic uncertainty and equilibrium selection in stable matching mechanisms. In particular, we apply a version of risk-dominance to compare the riskiness of “truncation” against other strategies that secure against remaining unmatched. By keeping subjects’ ordinal preferences fixed while changing their cardinal representation, our experimental treatments vary the risk-dominant prediction. We find that both truth-telling and truncation are played more often when they are risk-dominant. In both treatments, however, truncation strategies are played more often in later rounds of the experiment. Our results also shed light on several open questions in market design.

“Good policy” and “good luck” have been identified as two of the possible drivers of the “Great Moderation,” but their relative importance is still widely debated. This paper investigates the role played by equilibrium selection under indeterminacy in the assessment of their relative merits. We contrast the outcomes of counterfactual simulations conditional on the “continuity” selection strategy–largely exploited by the literature–with those obtained with a novel “sign restriction” based strategy. Our results suggest that conclusions achieved under “continuity” are not necessarily robust to the selection of different–still economically sensible–equilibria. According to our simulations, the switch to a hawkish systematic monetary policy may very well induce an increase in output volatility. Hence, our sign restriction–selection strategy “resurrects” the inflation–output policy tradeoff.

We recast Diamond's search equilibrium model into that with a finite number of agents. The state of the model is described by a jump-Markov process, the transition rates of which are functions of the reservation cost, which are endogenously determined by value maximization by rational agents. The existence of stochastic fluctuations causes the fraction of the employed to move from one basin of attraction to the other with positive probabilities when the dynamics have multiple equilibria. Stochastic asymmetric cycles that arise are quite different from the cycles of the set of Diamond–Fudenberg nonlinear deterministic differential equations. By taking the number of agents to infinity, we get a limiting probability distribution over the stationary state equilibria. This provides a natural basis for equilibrium selection in models with multiple equilibria, which is new in the economic literature.