Extensive Form Reasoning in Normal Form Games.

There is a tension between a belief in the strategic relevance of information sets and subgames and a belief in the sufficiency of the reduced normal form. The authors identify a prope rty of extensive form information sets and subgames termed strategic independence. Strategic independence is captured by the reduced norm al form and can be used to define normal form information sets and subgames. The authors prove a close relationship between these norma l form structures and their extensive form namesakes. They then motiva te and implement solution concepts corresponding to subgame perfection, sequential equilibrium, and forward induction entirely in the reduce d normal form. Copyright 1993 by The Econometric Society.