An interlock between two firms occurs if the firms share one or more directors in their boards of directors. We explore the effect of interlocks on firm performance for 101 large Dutch firms using a large and new panel database. We use five different performance measures, and for each...

Impact evaluations of development programmes usually focus on a comparison of participants with a control group. However, if the programme generates externalities for non-participants such an approach will capture only part of the programme’s impact. Based on a unique large-scale quantitative...

This discussion paper resulted in a publication in the <A HREF="http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9148929&fileId=S2050124213000209">'Network Science'</A>, 2014, 96(5), 936-948.<P> This paper analyzes the relationship between unexplained racial/ethnic wage differentials on the one hand and social network segregation, as measured by inbreeding homophily, on the other hand. Our...</p></a>

In experimental investigations of the effect of real incentives, accountability—the implicit or explicit expectation of a decision maker that she may have to justify her decisions in front of somebody else—is often confounded with the incentives themselves. This confounding of accountability...

This discussion paper resulted in an article in <I>Social Networks</I> (2013). Volume 35, issue 4, pages 541-560.<P> We use laboratory experiments to investigate how employers develop social structures for sharing information about the trustworthiness of job candidates, when worker opportunism is...</p></i>

Accepted for publication in the <I>Journal of Development Economics</I>.<P> This paper introduces the Small World model (Watts and Strogatz, Nature, 1998) into the theory of economic growth and investigates how increasing economic integration affects firm size and efficiency, norm enforcement, and...</p></i>

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>

This discussion paper led to a publication in 'Theory and Decision', 2008, 64, 519-536. A symmetric network consists of a set of positions and a set of bilateral links between these positions. Examples of such networks are exchange networks, communication networks, disease transmission networks,...

This paper reviews three distinct strategies in recent economics for using the concept of social identity in the explanation of individual behavior: Akerlof and Kranton’s neoclassical approach, Sen’s commitment approach, and Kirman et al.’s complexity approach. The primary focus is the...

See also <I>Social ties and coordination on negative reciprocity: The role of affect</I>, <A href="http://www.sciencedirect.com/science/article/pii/S0047272707000679">Journal of Public Economics'</A>, 2008, 92, 34-53.<P> This experimental study investigates how behavior changes after punishment for an unkind action. It also studies how fairness perceptions affect the reaction to...</p></a></i>