An Axiomatic Model of Social Adaptive Behavior.

I replace the assumption that an agent makes an optimal choice by an assumption that the agent executes a computational algorithm directed at finding a choice that is good at the time the choice is made. The algorithm utilizes the individual's own information, and information about choices of other members of society. It is shown that under some regularity conditions any such algorithm can be decomposed into generalized gradient dynamics, direct imitation, experimentation, and imitation of scope.BEHAVIOUR ; INFORMATION ; ECONOMIC MODELS

Quality Gaps

In this paper I consider a monopolistic screening model with continuum of types when the type set is a disconnected subset of the real line. I prove that the product line remains connected provided that the gap in the type space is sufficiently small. I also use the results to show that the inverse screening problem may be ill-defined.screening, product line, quality gap

Incentives for Boundedly Rational Agents.

This paper develops a theoretical framework for analyzing incentive schemes under bounded rationality. It starts from a standard principal-agent model and then superimposes an assumption of boundedly rational behavior on the part of the agent. Boundedly rational behavior is modeled as an explicit optimization procedure which combines gradient dynamics with a specific form of social learning called imitation of scope.RATIONALITY ; ECONOMIC MODELS ; BEHAVIOUR

A Noisy Model of Individual Behaviour.

This paper develops a model of individual adjustment subject to mistakes. In this case when mistakes are assumed i.i.d., this process produces a probability distribution of agents decision whose evolution is determined by Fokker-Planck equation. This distribution converges to the unique, globally stable stationary distribution. In the case when choice space is one dimensional this distribution satisfies Independence of Irrelevant Alternatives (IIA) property. In multidimensional case for IIA to hold strong additional conditions on payoff function or error structure should be satisfied. The paper also considers generalization of model for autocorrelated errors in one-dimensional case.WAGES ; DISTRIBUTION ; BEHAVIOUR

Why Do Social Skills Matter?

In this paper I propose a model where social skills of a manager signal the workers that their e¤ort is productive. In this model …rms with a high productivity of e¤ort hire a socially skilled manager and pay higher wages, and workers hired by these …rms exert higher e¤ort. In a broader context, the paper argues the employees are compensated with a higher wage and better working conditions for higher levels of effort.

Lie Groups of Partial Differential Equations and Their Application to the Multidimensional Screening Problems

In this paper I describe group theoretic methods that can be used for analyzing the boundary problems, which arise when the Hamiltonian method is applied to solve the relaxed problem for the multidimensional screening problem. This technique can provide some useful insights into the structure of solutions and some times may help to arrive at particular solutionsLie group, multidimensional screening

Heterogenous Human Capital: Life Cycle Investment in Health and Education

no abstract

Bounded Rationality:Static Versus Dynamic Approaches

Two kinds of theories of boundedly rational behavior are possible. Static theories focus on stationary behavior and do not include any explicit mechanism for temporal change. Dynamic theories, on the other hand, explicitly model the fine-grain adjustments made by the subjects in response to their recent experiences. The main contribution of this paper is to argue that the restrictions usually imposed on the distribution of choices in the static approach are generically not supported by a dynamic adjustment mechanism. The genericity here is understood both in the measure theoretic and in the topological sense.

The Employed, the Unemployed, and the Unemployable: Directed Search with Worker Heterogeneity

We examine the implications of worker heterogeneity on the equilibrium matching process, using a directed search model. Worker abilities are selected from a general distribution, subject to some weak regularity requirements, and the firms direct their job offers to workers. We identify conditions under which some fraction of the workforce will be "unemployable": no firm will approach them even though they offer positive surplus. For large markets we derive a simple closed form expression for the equilibrum matching function. This function has constant returns to scale and two new terms, which are functions of the underlying distribution of worker productivities: the percentage of unemployable workers, and a measure of heterogeneity (?).The equilibrium unemployment rate is increasing in ? and, under certain circumstances, is increasing in the productivity of highly skilled workers, despite endogenous entry. A key empirical prediction of the theory is that ? ? 1. We examine this prediction, using data from several countries.Directed search; worker heterogeneity; unemployment