Solving the simultaneous truel in The Weakest Link: Nash or revenge?

The game show The Weakest Link contains a version of the three-way duel, or truel, a strategic situation which historically has attracted considerable attention from economists and mathematicians. Data collected from actual episodes of the show provide an excellent opportunity to test behavioral motivations of this classic problem in a natural laboratory with substantial monetary payoffs. We use data from U.S., French, and British versions of the show and compute the Nash equilibria for each episode based on the maximization of monetary returns. We then analyze whether players play Nash strategies; whether their decisions are motivated by race, gender, or age discrimination; or whether they are motivated by reciprocity/revenge based on player interactions in previous rounds. There is only limited evidence that players play Nash equilibrium strategies or that they engage in race and age discrimination. The strongest predictor of behavior is reciprocity—players taking revenge on those voting against them in previous rounds.