A unified approach to comparative statics puzzles in experiments

Many experimental studies implement two versions of one game for which agents’ behavior is fundamentally different even though the Nash prediction is the same. This paper provides a novel explanation of such findings. Starting from the observation that many of the games under consideration satisfy the strategic-complementarity property, I obtain predictions for the direction of adjustment in response to parameter changes which do not require calculation of the equilibrium. I show that these predictions explain the experimental evidence very well. Further, I provide a behavioral justification of the approach, and I explore the relation to alternative explanations based on equilibrium selection theories and the quantal response equilibrium.