Drawing on a large database of publicly announced R&D alliances, we track the evolution of R&D networks in a large number of economic sectors over a long time period (1986-2009). Our main goal is to evaluate temporal and sectoral robustness of the main statistical properties of empirical R&D...

The authors develop an agent-based model to reproduce the size distribution of R&D alliances of firms. Agents are uniformly selected to initiate an alliance and to invite collaboration partners. These decide about acceptance based on an individual threshold that is compared with the utility...

We analyze input-output matrices for a wide set of countries as weighted directed networks. These graphs contain only 47 nodes, but they are almost fully connected and many have nodes with strong self-loops. We apply two measures: random walk centrality and one based on count-betweenness. Our...

In many economic and social contexts, individual players choose their partners and also decide ona mode of behavior in interactions with these partners. This paper develops a simple model toexamine the interaction between partner choice and individual behavior in games of coordination.An...

We investigate the trade-off between the risk-sharing gains enjoyed by more interconnected firms and the costs resulting from an increased risk exposure. We find that when the shock distribution displays “fat” tails, extreme segmentation into small components is optimal, while minimal...

We propose a stylized model of a problem-solving organization whose internal communication structure is given by a fixed network. Problems arrive randomly anywhere in this network and must find their way to their respective "specialized solvers" by relying on local information alone. The...

This paper models the dynamic process through which a large society may succeed in building up its "social capital" by establishing a stable and dense pattern of interaction among its members. In the model, agents interact according to a collection of infinitely repeated Prisoner's Dilemmas...

We propose a stylised dynamic model to understand the role of social networks in the phenomenon we call "globalization." This term refers to the process by which even agents who are geographically far apart come to interact, thus being able to overcome what would otherwise be a fast saturation...

In this paper, we propose a new approach to represent a country's outward orientation. Prior work mostly uses indicators of aggregate trade intensity, trade policy or trade restrictiveness. Our approach offers a broader perspective as it measures a country's level of integration not only by its...

Can large-scale peer interaction foster entrepreneurship and innovation? We conducted an RCT involving almost 5,000 entrepreneurs from 49 African countries. All were enrolled in an online business course, and the treatment involved random assignment to either face-to-face or virtual...