Nash equilibria of generalized games in normed spaces without upper semicontinuity (Q967236)

The present paper contains the proof of an existence theorem for the Nash equilibria of a noncooperative generalized game with infinite-dimensional strategy spaces. It extends a previous result by one of the authors [\textit{P. Cubiotti}, Int. J. Game Theory 26, No. 2, 267--273 (1997; Zbl 0881.90134)] to allow for the absence of upper semicontinuity assumptions on the constraint multifunctions (in the previous paper only the case of finite-dimensional strategy spaces was considered). Although the paper gives no explicit indication in this respect, the existence result delivered here indeed opens the way to several applications in economics and, more generally, in the social sciences, for the analysis of strategic problems in which the assumption of upper semicontinuity may not apply.