Whether they are financial, economic, or psychological, discount rates affect most economic decisions: investment and savings, hirings and firings, defaults and refinancing, financial and economic reforms, learning and experimentation, and any other decision with long-term consequences, such as...

We consider an observer who makes a finite number of observations of an industry producing a homogeneous good, where each observation consists of the market price and firm specific production quantities.  We develop a revealed preference test (in the form of a linear program) for the hypothesis...

These are additional notes relating to the paper `The Comparative Statics of Constrained Optimization Problems`, which is appearing in Econometrica. It gathers together material present in various earlier versions of the paper, as well as some new material, which are not found in the published...

In a monetary policy model incorporating partial persistence in inflation it is shown that inflation bias is reduced and the response to shocks improved if the policy maker has a discount rate lower than its true social value. Thus a patient central banker is shown to be a third mechanism for...

This paper gives a non-fixed point theoretic proof of equilibrium existence when the excess demand function of an exchange economy obeys the weak axiom. The proof is simple and geometrically intuitive, and it also permits a weakening of the continuity assumption on the excess demand function....

We identify necessary and sufficient conditions under which a finite data set of price vectors and consumption bundles can be rationalized by a weakly separable utility function.  Our result could be understood as a generalization of Afriat's Theorem.

Consider a finite data set of price vectors and consumption bundles; under what conditions will there be a weakly separable utlity function that rationalizes the data?  This paper shows that rationalization in this sense is possible if and only if there exists a preference order on some finite...

We identify a natural way of ordering functions, which we call the interval dominance order and develop a theory of monotone comparative statistics based on this order.  This way of ordering functions is weaker than the standard one based on the single crossing property (Milgrom and Shannon,...

We focus on the management of highly persistent shocks to aid flows, including HIPC or MDG-related increases in net flows, in the presence of currency substitution by the domestic private sector. Such shocks have beneficient long-run effects, but when currency substitution is high they can...

Opportunist land encroachment, resulting from costly and incomplete enforcement of common land boundaries, is a problem in many less-developed countries. A multi-period model of such encroachment is presented in this paper. The model accounts explicitly for the cumulative effects of...