Re®nements of rationalizability for normal-form games*
نویسندگان
چکیده
There exist three equivalent de®nitions of perfect Nash equilibria which di ̈er in the way ``best responses against small perturbations'' are de®ned. It is shown that applying the spirit of these de®nitions to rationalizability leads to three di ̈erent re®nements of rationalizable strategies which are termed perfect (Bernheim, 1984), weakly perfect and trembling-hand perfect rationalizability, respectively. We prove that weakly perfect rationalizability is weaker than both perfect and proper (Schuhmacher, 1995) rationalizability and in two-player games it is weaker than trembling-hand perfect rationalizability. By means of examples, it is shown that no other relationships can be found.
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