Gabriele K. Lünser

Automatic imitation in a strategic context: players of rock–paper–scissors imitate opponents' gestures†

A compelling body of evidence indicates that observing a task-irrelevant action makes the execution of that action more likely. However, it remains unclear whether this ‘automatic imitation’ effect is indeed automatic or whether the imitative action is voluntary. The present study tested the automaticity of automatic imitation by asking whether it occurs in a strategic context where it reduces payoffs. Participants were required to play rock–paper–scissors, with the aim of achieving as many wins as possible, while either one or both players were blindfolded. While the frequency of draws in the blind–blind condition was precisely that expected at chance, the frequency of draws in the blind–sighted condition was significantly elevated. Specifically, the execution of either a rock or scissors gesture by the blind player was predictive of an imitative response by the sighted player. That automatic imitation emerges in a context where imitation reduces payoffs accords with its ‘automatic’ description, and implies that these effects are more akin to involuntary than to voluntary actions. These data represent the first evidence of automatic imitation in a strategic context, and challenge the abstraction from physical aspects of social interaction typical in economic and game theory.

On the Competition of Asymmetric Agents

Abstract Rank-order tournaments are usually implemented in organizations to provide incentives for eliciting employees’ effort and/or to identify the agent with the higher ability, for example in promotion tournaments. We close a gap in the literature by experimentally analyzing a ceteris paribus variation of the prize spread - being the major design feature of tournaments - in a symmetric and an asymmetric setting. We find that effort significantly increases with the prize spread as predicted by standard theory. However, only for sufficiently large prize spreads weak players competing against strong players strain themselves all the more and sorting of agents is feasible.

Medical insurance and free choice of physician shape patient overtreatment: A laboratory experiment

In a laboratory experiment designed to capture key aspects of the interaction between physicians and patients in a stylized way, we study the effects of medical insurance and competition in the guise of free choice of physician. Medical treatment is an example of a credence good: only the physician (but not the patient) knows the appropriate treatment, and even after consulting, the patient is not sure whether he got proper treatment or got an unnecessary treatment, i.e. was overtreated. We find that with insurance, moral hazard looms on both sides of the market: patients consult more often and physicians overtreat more often than in the baseline condition. Competition decreases overtreatment compared to the baseline and patients therefore consult more often. When the two institutions are combined, competition is found to partially offset the adverse effects of insurance: most patients seek treatment, but overtreatment is moderated.