Erschienen in:FEUNL Working Paper Series ; No. 488
Umfang:
1 Online-Ressource (30 p)
Sprache:
Englisch
DOI:
10.2139/ssrn.921803
Identifikator:
Entstehung:
Anmerkungen:
Nach Informationen von SSRN wurde die ursprüngliche Fassung des Dokuments 2006 erstellt
Beschreibung:
Radzik (1991) showed that two-player games on compact intervals of the real line have { equilibria for all greater than 0, provided that payo functions are upper semicontinuous and strongly quasi-concave. In an attempt to generalize this theorem, Ziad (1997) stated that the same is true for n-player games on compact, convex subsets of Rm, m greater than 1 provided that we strengthen the upper semicontinuity condition. We show that:1. the action spaces need to be polyhedral in order for Ziad's approach to work,2. Ziad's strong upper semicontinuity condition is equivalent to some form of quasi-polyhedral concavity of players' value functions in simple games, and3. Radzik's Theorem is a corollary of (the corrected) Ziad's result