Small Worlds and Regional Innovation

S networks have attracted much theoretical attention and are widely thought to enhance creativity. Yet empirical studies of their evolution and evidence of their benefits remain scarce. We develop and exploit a novel database on patent coauthorship to investigate the effects of collaboration networks on innovation. Our analysis reveals the existence of regional small-world structures and the emergence and disappearance of giant components in patent collaboration networks. Using statistical models, we test and fail to find evidence that small-world structure (cohesive clusters connected by occasional nonlocal ties) enhances innovative productivity within geographic regions. We do find that both shorter path lengths and larger connected components correlate with increased innovation. We discuss the implications of our findings for future social network research and theory as well as regional innovation policies.