Often, perfect bayesian equilibrium is loosely defined by stating that players should be sequentially rational given some beliefs in which Bayes rule is applied “whenever possible”. We show that there are games in which it is not clear what “whenever possible” means. Then, we provide a...

I examine a search model a la' Burdett and Judd (1983). Consumers are embedded in a consumers network, they may costly search for price quotations and the information gathered are non-excludable along direct links. This allows me to explore the effect of endogenous consumers externalities on...

The important role of friends, neighbors and colleagues in shaping individual choices has been brought out in a number of studies over the years. The presence of significant ‘local’ influence in shaping individual behavior suggests that firms, governments and developmental agencies should...

We study a simultaneous move game of targeted advertising and pricing in a market with various consumer segments. In this setting we explore the implications of market segmentation on firm competitiveness. If firms are unable to target their ads on different consumer segments, a unique...

What makes you popular at school? And what are the labor market returns to popularity? We investigate these questions using an objective measure of popularity derived from sociometric theory: the number of friendship nominations received from schoolmates, interpreted as a measure of early...

This paper studies network formation in settings where players are heterogeneous with respect to benefits as well as the costs of forming links. Our results demonstrate that centrality, center-sponsorship and short network diameter are robust features of equilibrium networks. We find that in a...

A fundamental question in social sciences is how trust emerges. We provide an answer which relies on the formation of social and economic relationships. We argue that behind trust lies the fact that individuals invest in connections taking into account the potential externalities networks...