Considered here is on-line portfolio management aimed at maximizing the long-run growth of financial wealth. The portfolio is repeatedly rebalanced in response to observed returns on diverse assets. Suppose statistical information and related methods are not available - or deemed too diffcult....

Motivated by emission and resource markets, this paper considers repeated, bilateral barters between owners of commodity bundles, contingent claims, or property rights. Focus is on feasible, voluntary exchanges, driven only by differences in substitution rates. No coordination is ever needed....

This paper considers a fairly large class of non-cooperative games in which strategies are jointly constrained. When what is called the Ky Fan or Nikaidô-Isoda function is convex-concave, selected Nash equilibria correspond to diagonal saddle points of that function. This feature is exploited...

We exhibit a quite natural, adaptive process generated by price-taking, noncooperative firms, supply the same market. Under rather mild conditions, that process. being driven by marginal profits, converges to a market clearing, Cournot-Nash equilibrium. Namely, it suffices for convergence that...

We show that social disability insurance may better society-wide welfare even when there is a perfect private market for similar insurance. In essence, the public system complements the private. The latter cover risks when personal characteristics are known, whereas the first mitigates effects...