Learning and decision costs in experimental constant sum games

Subjects played strategically similar 4 x 4 and 6 x 6 constant sum games under varying payoff scales. Substantial divergences from equilibrium predictions were exhibited. The dynamic pattern of play is best explained by a stimulus learning model whereby players allocate weight to different actions according to their relative (time average) payoff experience in past plays. The results do not provide much support for the hypothesis that players select best responses to beliefs about opponent play based on observed choice frequencies in past plays, modified by random errors or preference shocks. (C) 1997 Academic Press.