This discussion paper led to a publication in the <A href="http://www.degruyter.com/view/j/rne.2011.10.2/rne.2011.10.2.1278/rne.2011.10.2.1278.xml">'Review of Network Economics'</A>, 2011, 10(2), 1-20.<P> In this paper we test the celebrated `Strength of weak ties' theory of Granovetter (1973). We test two hypotheses on the network structure in a data set of collaborating economists. While we find...</p></a>

We examine the incentives of regions in a country to unite or toseparate. We find that smaller regions have greater incentives tounite, relative to larger regions. We show, however, that on thewhole, majority voting on separation and union generates excessiveincentives to separate. This leads us...

Connections between individuals facilitate the exchange of goods, resources, and information and create benefits. These connections may be exploited by adversaries to spread their attacks as well. What is the optimal way to design and defend networks in the face of attacks? We develop a model...