Shapiro-Shapley introduce their 1961 memorandum (published 17 years later as Shapiro-Shapley (1978)) with the remark that \institutions having a large number of competing participants are common in political and economic life, and cite as examples \markets, exchanges, corporations (from the...

For market with an atomless continuum of assets, we formulate the intuitive idea of a well-diversified portfolio, and present a notion of exact arbitrage, strictly weaker than the more conventional notion of asymptotic arbitrage, and necessary and sufficient for the validity of an APT pricing...

We provide a detailed portfolio analysis for a financial market with an atomless continuum of assets. In the context of an exact arbitrage pricing theory (EAPT), we go beyond the characterization of the existence of important portfolios (normalized riskless, mean, cost, factor and mean-variance...

We present proofs, based on the Shapley-Folkman theorem, of the convexity of the range of a strongly continuous, finitely additive easure, as well as that of an atomless, countably additive measure. We also present proofs, based on diagonalization and separation arguments respectively, of the...

This paper offers a sufficient condition, based on Maharam (1942) and re-emphasized by Hoover-Keisler (1984), for the validity of Lyapunov's (1940) theorem on the range of an atomless vector measure taking values in an infinite-dimensional Banach space that is not necessarily separable nor has...

We present a comprehensive theory of large non-anonymous games in which agents have a name and a determinate social-type and/or biological trait to resolve the dissonance of a (matching-pennies type) game with an exact pure-strategy Nash equilibrium with finite agents, but without one when...

A game of love and hate is one in which a player's payoff is a function of her own action and the payoffs of other players. For each action profile, the associated payoff profile solves an interdependent utility system, and if that solution is bounded and unique for every profile we call the...

Harsanyi (1974) criticized the von Neumann-Morgenstern notion of a stable set on the grounds that it implicitly assumes coalitions to be shortsighted in evaluating their prospects. He proposed a modification of the dominance relation to incorporate farsightedness. In doing so, however, Harsanyi...

This chapter surveys the sizable and growing literature on coalition formation. We refer to theories in which one or more groups of agents (“coalitions”) deliberately get together to jointly determine their actions. The defining idea of a coalition, in this chapter, is that of a group which...

We provide a characterization of virtual Bayesian implementation in pure strategies for environments satisfying no-total-indifference. A social choice function in such environments is virtually Bayesian implementable if and only if it satisfies incentive compatibility and a condition we term...