This paper uses the television game show 'Jeopardy!' as a natural experiment to analyze behavior under uncertainty and the ability of players to choose strategic best-responses. The results suggest that, while most players bet in a rational manner, the failure rate for choosing best-responses increases as the betting problem grows more complex and that players' choices are affected by the 'frame' of the problem. However, suboptimal betting tends to decrease as inferior players are driven from the game. The data also allow for estimation of the extent of risk aversion; the results imply near risk-neutrality. Copyright 1995 by American Economic Association.