Social Networks and Interactions in Cities

Reprint No. 2014:12

Author(s): Robert W. Helsley and Yves ZenouYear: 2014 Title: Journal of Economic Theory Volume (No.): 150 (March) Pages: 426–466
Online article (restrictions may apply)

We examine how interaction choices depend on the interplay of social and physical distance, and show that agents who are more central in the social network, or are located closer to the geographic center of interaction, choose higher levels of interactions in equilibrium. As a result, the level of interactivity in the economy as a whole will rise with the density of links in the social network and with the degree to which agents are clustered in physical space. When agents can choose geographic locations, there is a tendency for those who are more central in the social network to locate closer to the interaction center, leading to a form of endogenous geographic separation based on social distance. We also show that the market equilibrium is not optimal because of social externalities. We determine the value of the subsidy to interactions that could support the first-best allocation as an equilibrium. Finally, we interpret our model in terms of labor-market networks and show that the lack of good job contacts would be here a structural consequence of the social isolation of inner-city neighborhoods.

Helsley, Robert W. and Yves Zenou (2014), "Social Networks and Interactions in Cities". Journal of Economic Theory 150(March), 426–466.

Sick of Inequality?

An Introduction to the Relationship between Inequality and Health

Sick of Inequality.jpg

In this book Andreas Bergh, Therese Nilsson, IFN and Lund University, and Daniel Waldenström, IFN and Paris School of Economics, France, review the latest research on the relationship between inequality and health. What does inequality mean for our health? Does increasing income inequality affect outcomes such as obesity, life expectancy and subjective well-being?


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