. We approach this gap by analyzing the role of positive and negative externalities of link formation. We find general … results that relate situations of positive externalities with stable networks that cannot be "too dense" in a well …-defined sense, while situations with negative externalities, tend to induce "too dense" networks. …

. We approach this omission by analyzing the role of positive and negative externalities of link formation. This yields … general results that relate situations of positive externalities with stable networks that cannot be “too dense” in a well …-defined sense, while situations with negative externalities tend to induce “too dense” networks. …

and a rich set of externalities that are responsible for possible wedges between the equilibrium and the efficient … acquisition of information. First, we relate the (in)efficiency in the acquisition of information to the (in)efficiency in the use … of information and explain why efficiency in the use does not guarantee efficiency in the acquisition. Next, we show how …

, the less likely cooperation will be. …

behavior. I show that for a large class of parameters cooperation will emerge if the population is large; if the population is … population, the less likely cooperation will be. <BR><BR> …

. This raises the important issue of just how such voluntary cooperation might be obtained. In this paper, we explore the …