Recently, Mankiw-Whinston (1986) and Suzumura-Kiyono (1987) have shown that socially excessive firm entry occurs in unregulated oligopoly. This paper extends this "excess entry" results by looking into strategic aspects of cost-reducing R&D investment that creates incentives towards socially...

We provide characterizations of four new rules for individual decision-making under complete uncertainty. They are what we call the min-max rule, the max-min rule, the lexicographic min-max rule and the lexicographic max-min rule. These rules provide orderings of the sets of possible outcomes...

We analyze the rationalizability of variable-population social-choice functions in a welfarist framework. It is shown that fixed-population rationalizability and a weakening of congruence together are necessary and sufficient for rational choice, given a plausible dominance property that...

We provide a characterization of selection correspondences in two-person exchange economies that can be core rationalized in the sense that there exists a preference profile with some standard properties that generates the observed choices as the set of core elements of the economy for any given...

In this note, it is shown that a result due to Uzawa showing that the weak axiom of revealed preference together with a regularity condition implies the strong axiom of revealed preference can be derived from the regularity condition alone, if the choice function is continuous in prices and in...