This paper establishes sufficient conditions for the existence of a stable coalition structure in the coalition unanimity game of coalition formation, first defined by Hart and Kurz (1983) and more recently studied by Yi (1997, 2000). Our conditions are defined on the strategic form game used to...

We study the stability properties of organizations in partition function games, describing cooperative situations with externalities. An organization is defined as a group of agents, together with a set of bilateral relations, formally, a connected graph. Because of the presence of...

We study the group stability of collective decision making when society is organized according to a non directed graph, and groups' payoff possibilities are given by a partition function. We focus on the stability properties of hierarchical organizations, formally described by minimally...

Recent research in the field of network economics has shown how explicitly modelling the network structure of social and economic relations can provide significant theoretical insights, as well as account for previously unexplained empirical evidence. Despite their critical importance to many...

Many types of economic and social activities involve significant behavioral complementarities (peer effects) with neighbors in the social network. The same activities often exert externalities that cumulate in "stocks" affecting agents' welfare and incentives. For instance, smoking is subject to...

We study the bilateral exchange of information in the context of linear quadratic games. An information structure is here represented by a non directed network, whose nodes are agents and whose links represent sharing agreements. We first study the equilibrium use of information in any given...

We consider a game of information transmission, with one informed decision maker gathering information from one or more informed senders. Private information is (conditionally) correlated across players, and communication is cheap talk. For the one sender case, we show that correlation...

Many Social Interactions display either or both of the following well documented phenomena. People tend to interact with similar others (homophily). And they tend to treat others more favorably if they are perceived to share the same identity (in-group bias). While both phenomena involve some...

In an economy where consumers are heterogeneous in their preferences over the hedonic and environmental attributes of goods on sale, we explore the effects of anti-consumerism and environmentalism. We show that when the environmental attributes of products come at the expense of the hedonic...

We investigate whether climate activism favors pro-environmental consumption by examining the impact of Fridays for Future (FFF) protests in Italy on second-hand automobile transactions in the strike-affected areas. Leveraging data on 10 million automobile transactions occurring before and after...