We develop a novel theoretical framework for studying ecosystems in which interacting state variables which are affected by management decisions diffuse in space. We identify (i) mechanisms creating spatial patterns when economic agents maximize profit at each site by ignoring the impact of...

The aim of the paper is to develop a discrete time version of a one-sector optimal growth model with endogenous time preference. The intertemporal discount rate is determined by social factors (i.e., factors that are external to the individual agent), namely the economy wide levels of...

While the well-known Pratt-Arrow measure of risk premium is useful in studying local risks, this paper introduces new measures to cope with non-trivial risks, including default. The premia derived are cast in terms of life-time and instantaneous utilities and required income. the results follow...

Integer linear fractional programming problem with multiple objective MOILFP is an important field of research and has not received as much attention as did multiple objective linear fractional programming. In this work, we develop a branch and cut algorithm based on continuous fractional...

Programs that work very well in optimizing convex functions very often perform poorly when the problem has multiple local minima or maxima. They are often caught or trapped in the local minima/maxima. Several methods have been developed to escape from being caught in such local optima. The...

For a class of aggregative optimal growth models, which allow for a non-convex and non-differentiable production technology, this paper examines whether the set of utilitarian maximal programs coincides with the set of weakly maximal programs. It identifies a condition, called the...

We present the blueprints for a set of innovative reverse shooting algorithms that trap the global saddle path in systems with 2-4 state variables. The solution procedure is built around a new distance mapping and refined simplex algorithms. Since the algorithms are completely reliable and...

We ask whether offering a menu of unemployment insurance contracts is welfare improving in a heterogeneous population. We adopt a repeated moral-hazard framework as in Shavell/Weiss (1979) supplemented by unobserved heterogeneity about agents’ job opportunities. Our main theoretical...

We ask whether offering a menu of unemployment insurance contracts is welfare-improving in a heterogeneous population. We adopt a repeated moral hazard framework as in Shavell/Weiss (1979), supplemented by unobserved heterogeneity about agents’ job opportunities. Our main theoretical...

A well-known pitfall of Markowitz (1952) portfolio optimization is that the sample covariance matrix, which is a critical input, is very erroneous when there are many assets to choose from. If unchecked, this phenomenon skews the optimizer towards extreme weights that tend to perform poorly in...