An appropriate (interim) notion of the core for an economy with incomplete information depends on the amount of information that coalitions can share. The coarse and fine core, as originally defined by Wilson (1978), correspond to two polar cases, involving no information sharing and arbitrary...

When alternatives are compared using an estimated criterion function, this may introduce a discrepancy between the true and the estimated criterion. In this paper, we consider a situation where a preordering (ranking) of stochastic sequences is defined from expected loss/gain, using a parametric...

It is known that the incompleteness of asset markets causes inefficiency in almost every equilibrium. Yet unexplored is the ”size” of this inefficiency. The size of a Pareto improvement is the total willingness to pay for it, out of current consumption. Inefficiency is the maximum size of...

We consider robust virtual implementation, where robustness is the requirement that implementation succeed in all type spaces consistent with a given payoff type space as well as with a given space of first-order beliefs about the other agents’ payoff types. This last bit, which constitutes...

This paper applies the Model Confidence Set (MCS) procedure of Hansen, Lunde, and Nason (2003) to a set of volatility models. A MCS is analogous to confidence interval of a parameter in the sense that the former contains the best forecasting model with a certain probability. The key to the MCS...

We present a model where groups attempt to exert influence on policies using both bribes (plata, Spanish for silver) and the threat of punishment (plomo, Spanish for lead). We then use it to make predictions about the quality of a country’s public officials and to understand the role of...

Mounting evidence suggests that the outcomes of laboratory public goods games, and collective action in firms, communities, and polities, reflect the presence in most groups of individuals having differing preferences and beliefs. We designed a public goods experiment with targeted punishment...

This paper develops an explanation for historical differences in the ways in which territorial disputes between sovereign states have been resolved. The main innovation in the analysis is to allow for three possible equilibria: • an unfortified border; • a fortified but peaceful border; and...