On the Existence of Equilibrium for Abstract Economies

In this paper, several existence theorems for abstract economies have been established, They are natural modifications (strict generalizations when strategy spaces are metrizable) of the main results of Yannelis and Prabhakar [23], Tulcea [22], and Ding, Kim, and Tan [10] for infinite-dimensional casas. For the finite-dimensional case, we show that the topological conditions on correspondences in Shafer and Sonnenschein′s result [20] can be much weaker. Along the proofs, several propositions are established, which are of independent interest. We also show that many existence results in fixed point theory, maximization theory, and generalized quasi-variational inequalities can be