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 support for the hypothesis of transitivity of strong ties, we reject the hypothesis that weak ties...

This study analyses 1400 research projects of the top 20 R&D-spending pharmaceuticals to identify the determinants of successful research projects. We provide clear evidence that externally sourced projects and projects involving biotechnologies perform better than internal projects and chemical...

This paper describes a classroom experiment that illustrates the research and development investment incentives facing firms when technological spillovers are present. The game involves two stages in which student sellers first make investment decisions then production decisions. The classroom...

Social norms permeate society across a wide range of issues and are important to understanding how societies function. In this paper we concentrate on 'bad' social norms - those that are inefficient or even damaging to a group. This paper explains how bad social norms evolve and persist; our...