The weakest link: a field experiment in rational decision making

We analyze the BBC TV game show “The Weakest Link”, using data from 77 episodes, covering 13,380 questions. We focus on the banking decision, where a contestant chooses to secure an amount of money for the eventual winner, or to risk it on a general knowledge question. In the latter case, should he answer correctly, the amount at stake increases exponentially. We show that banking decisions are not rational: a crude rule of thumb performs substantially better than the contestants’ strategies. Yet, at least to some extent, contestants do take into account their own ability and the fact that questions are progressively more difficult