The Latent Topic Block Model for the Co-Clustering of Textual Interaction Data

in Computational Statistics and Data Analysis (2019), 137

How do inventor networks affect urban invention?

in Regional Science and Urban Economics (2018), 71

Social networks are expected to matter for invention in cities, but empirical evidence is still puzzling. In this paper, we provide new results on urban patenting covering more than twenty years of ... [more ▼]

Social networks are expected to matter for invention in cities, but empirical evidence is still puzzling. In this paper, we provide new results on urban patenting covering more than twenty years of European patents invented by nearly one hundred thousand inventors located in France. Elaborating on the recent economic literatures on peer effects and on games in social networks, we assume that the productivity of an inventor’s efforts is positively affected by the efforts of his or her partners and negatively by the number of these partners’ connections. In this framework, inventors’ equilibrium outcomes are proportional to the square of their network centrality, which encompasses, as special cases, several well-known forms of centrality (Degree, Katz-Bonacich, Page-Rank). Our empirical results show that urban inventors benefit from their collaboration network. Their production increases when they collaborate with more central agents and when they have more collaborations. Our estimations suggest that inventors’ productivity grows sublinearly with the efforts of direct partners, and that they incur no negative externality from them having many partners. Overall, we estimate that a one standard deviation increase in local inventors’ centrality raises future urban patenting by 13%. [less ▲]

Network proximity in the geography of research collaboration

in Papers in Regional Science (2017), 96(4),

This paper deals with the questions of how network proximity influences the structure of inter-regional collaborations and how it interacts with geography. I first introduce a new, theoretically grounded ... [more ▼]

This paper deals with the questions of how network proximity influences the structure of inter-regional collaborations and how it interacts with geography. I first introduce a new, theoretically grounded measure of inter-regional network proximity. Then, I use data on European scientific co-publications in the field of chemistry between 2001 and 2005 to assess those questions. The main findings reveal that inter-regional network proximity is important in determining future collaborations but its effect is mediated by geography. Most importantly, a clear substitution pattern is revealed showing that network proximity mainly benefits international collaborations. [less ▲]

Centrality of regions in R&D networks: A new measurement approach using the concept of bridging paths

in Regional Studies (2017), 51(8), 1165--1178

This paper aims at introducing a novel measure of regional centrality in the context of R&D networks. We first demonstrate some substantial problems of SNA-based centrality measures to cope with regional ... [more ▼]

This paper aims at introducing a novel measure of regional centrality in the context of R&D networks. We first demonstrate some substantial problems of SNA-based centrality measures to cope with regional R&D networks in a meaningful way. Then, we introduce a new measurement approach of regional network centrality based on the concept of inter-regional bridging paths (indirect connections at the regional level). We show that the formal definition of our regional bridging centrality measure can be expressed in terms of three simple components: the participation intensity of a region in inter-regional R&D collaborations, the relative outward orientation in terms of all established links and the diversification of R&D collaborations among partner regions. We illustrate the measure and its behaviour with respect to other conventional centrality measures by using the example of the European co-patent network at the NUTS2 level. [less ▲]

Centrality of regions in R&D networks: Conceptual clarifications and a new measure

E-print/Working paper (2015)

This paper aims at introducing a novel measure of regional centrality in the context of R&D networks. We first demonstrate some substantial problems of SNA-based centrality measures to cope with regional ... [more ▼]

This paper aims at introducing a novel measure of regional centrality in the context of R&D networks. We first demonstrate some substantial problems of SNA-based centrality measures to cope with regional R&D networks in a meaningful way. Then, we introduce a new measurement approach of regional network centrality based on the concept of inter-regional bridging paths (indirect connections at the regional level). We show that the formal definition of our regional bridging centrality measure can be expressed in terms of three simple components: the participation intensity of a region in inter-regional R&D collaborations, the relative outward orientation in terms of all established links and the diversification of R&D collaborations among partner regions. We illustrate the measure and its behaviour with respect to other conventional centrality measures by using the European co-patent network at the NUTS 2 level. [less ▲]