Abstract :
In this paper, by developing an approximation approach which is originally due
to Tuleca in 1986, we prove the existence of equilibria for generalized games in
which constraint mappings correspondences.are lower resp., upper. semicontinu-
ous instead of having lower resp., upper.open sections or open graphs in infinite
dimensional topological spaces. Then, existence theorems of solutions for quasivariational
inequalities and non-compact generalized quasi-variational inequalities
are also established. Finally, existence theorems of constrained games with noncompact
strategy sets are derived. Our results unify and generalize many well
known results given in the existing literature. In particular, we answer the question
raised by Yannelis and Prabhakar in 1983 in the affirmative under more weaker
conditions