Why are Good Comparative Studies of Networks so Rare? Practical Lessons from a Study on French Clusters

French “competitiveness clusters” were set up in 2005 to strengthen cooperation between small and large enterprises, and training and research institutions working on similar topics and located in the same geographical area, with the aim of making this area more competitive and attractive through enhanced innovation. Our analysis of this set of about 70 apparently similar networks, on which much data were collected, has given us an opportunity to investigate the factors explaining the differences in their performance.In attempting this analysis, we encounter several difficulties, such as, how can we:(1) measure a cluster's performance?(2) characterize its context and resources?(3) characterize the governance of the network and the actions it takes?(4) deal with the fact that the network's boundaries evolve due to both the fluctuating commitment of some stakeholders and the implementation of the cluster's strategy, which changes the context and the available resources?(5) deal with actors' learning at all levels (i.e., the cluster's members, organization, rulers and fund providers), which changes the rules of the game while the game is still being played?Last but not least, the networks that we have taken to be homologous because they have been selected, labelled and regulated by the same rules, actually display significant qualitative differences. There may be different kinds of clusters following substantially different performance models. We could then define a cluster typology so that comparisons would be much more relevant between clusters of the same class. This could eventually lead us to create performance indicators adapted to the specificities of each class of clusters and improve the monitoring of individual clusters and of the national cluster policy