The phenomenon of electronic commerce has led to a proliferation of web sites competing for the attention and resources of millions of consumers. As has been recently shown, the resulting dynamics is such that a few sites command most of the traffic in the web, a signature of a winner-take-all...

A number of papers have studied imperfect imitative learning as a utility-increasing activity (e.g. Dawid, McCain 2000). Some studies of imitative learning have taken account of the tendency of people to imitate others who are "near" them in some sense (e.g. McCain 2000, Bala and Goyal). As...

Let us consider the ordinary linear model Y = X*beta +Z, where Y is a vector of observations of the dependent variable, X is a matrix of the observations of explanatory variables, (beta) is a vector of unknown regression coefficients and Z is a vector of random disturbances (all quantities of...

In this paper we concentrate on the estimation of loss functions using nonparametric methods. We focus on the parametric transformation approach to kernel smoothing introduced by Wand, Marron and Ruppert (1991) and compare it with the standard kernel estimator and the multiplicative bias...

Consider a simple economy in which autonomous agents are endowed with two goods, g1 and g2, and with the capability of producing more of each. At regular intervals each agent is allowed to produce one of the goods, at a rate determined by his own unique production function, or to trade with...

In this paper we test computationally the performance of CAPM in an evolutionary setting. In particular we study the stability of wealth distribution in a financial market where some traders invest as prescribed by CAPM and others behave according to different portfolio rules. Our study is...

For the last few years the internet has profoundly affected the retail trade of standarized consumer goods, from books and CDs to intercontinental flights. For a single product, consumers enjoy a wide choice of offers and can easily compare prices making use of the decreased effort of...

The appearance of long-range dependence has been observed in a wide variety of real-word time series. So called long-memory models, which exhibit a slowly decaying autocovariance sequence and a pole at frequency zero in their spectral density function, have been used to characterize long-range...

The effective conduct of monetary policy is hampered by uncertainty surrounding the level of potential output. Here, the case for following a more aggressive policy to learn about the economy is considered in a model where potential output is changing over time. Following such a policy may be...

Multilayer neural network has been successfully applied to the time series forecasting. Backpropagation, a popular learning algorithm, converges slowly and has the difficulty in determining the network parameters. In this paper, conjugate gradient learning algorithm with restart procedure is...