Conditions for equivalence between sequentiality and subgame perfection (Q926229)

The authors study equilibrium properties of finite extensive form games \(\Gamma\) with perfect recall. In their interesting paper, they analyze the following sets: subgame perfect equilibria (SPE(\(\Gamma\))), sequential equilibria (SQE(\(\Gamma\))), subgame perfect equilibrium outcomes (SPEO(\(\Gamma\))) and sequential equilibrium outcomes (SQEO(\(\Gamma\))). Two interesting and nontrivial results have been obtained. In the first one, necessary and sufficient conditions are given for games \(\Gamma\) to satisfy the property, SPE(\(\Gamma\)) = SQE(\(\Gamma\)) for all payoff vectors. The second result gives the same for the property, SPEO(\(\Gamma\)) = SQEO(\(\Gamma\)) for all payoff vectors. The paper ends with several examples of models discussed in the literature and related to the obtained results in the paper. It is worth mentioning that the paper is exceptionally clearly written and it can be very helpful also for readers who would want to quickly familiarize with all the basic notions of theory of extensive form games and various types of equilibria considered there.