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...

This note determines the precise connection between an agent`s attitude towards income risks and his attitude over risks in the underlying consumption space. Our results follow a general mathematical theory connecting the curvature properties of an objective function with the ray-curvature...

Optimal monetary policy is sensitive to the Phillips curve specification used to represent the dynamics of inflation and output. Most recent literature has used a new Keynesian Phillips Curve based on Calvo pricing. This paper shows that this workhorse model is not robust to relatively minor...

The single crossing property plays a crucial role in monotone comparative statics (Milgrom and Shannon (1994)), yet in some important applications the property cannot be directly assumed or easily derived.  Difficulties often arise because the property cannot be aggregated: the sum of two...

An observer makes a number of observations of an industry producing a homogeneous good.  Each observation consists of the market price, the output of individual firms and perhaps information on each firm's production cost.  We provide various tests (typically, linear programs) with which the...

This paper extends and modifies the Keynesian critique of inflation targeting with reference to stabilisation policy in emerging market economies. The IMF `basic monetary programming framework` for developing countries uses government borrowing and the exchange rate as policy instruments in...