Research university assortativity conditions the integration of regional innovation systems

Substantial policy efforts to develop regional innovation systems (RIS) highlight the importance of understanding the institutional factors that promote integration and synergy at the regional scale. To this end, we analyzed historical patterns of research co-production within and across California (CA) and Texas (TX), two US regions that account for >5% of global research publication. This predominance is largely attributed to the University of California and the University of Texas, two multi-campus university systems (MUS) that feature distinct configurations of institutional research specialization. We exploit these differences to analyze four institutional assortativity channels that foster RIS synergy: institutional proximity, prestige, homophily, and specialization. Descriptive analysis reveals that institutional co-publication rates differ within and across RIS and are influenced by external socio-economic shocks, such as the 2007-08 financial crisis, which intensified institutional clustering within these research university ecosystems. We also develop institutional specialization profiles for exploring the structure and role of institutional alignment within RIS. Results indicate that regional integration is mediated by the alignment of institutional specialization and moderated by institutional homophily. These findings underscore the critical role of the MUS backbone that supports RIS integration and generates resiliency to socio-economic shocks. Moreover, MUS provide institutional redundancy and variation that generates a broad combinatorial space fostering multi-university research synergies. All together our framework can help address the innovator’s dilemma of whether to exploit institution-specific capabilities or to strategically identify and invest in novel multi-institutional synergies that leverage the complex configurational space of institutional specializations that uniquely characterize each RIS.Author summary: We analyze the structure and dynamics of regional scientific integration in California and Texas, two U.S. states with distinct research university (RU) ecosystems. By leveraging these differences, we develop a framework for understanding how institutional assortativity – defined as similarities that sustain research partnerships across time and space – drives integration and defines the structure of regional innovation systems (RIS). Our analysis offers practical insights for research development offices working to identify strategic research priorities and foster multi-university collaborations, particularly in the face of the organizational innovator’s dilemma: whether to focus on existing institutional strengths or pursue new, cross-institutional opportunities. It also provides guidance for national agencies making place-based investments in specialized infrastructure and institutional partnerships that support emerging technologies. From a systems science perspective, we highlight the vulnerability of RU ecosystems to large-scale socio-economic shocks, such as the 2007-08 financial crisis, and underscore the critical roles of institutional diversity and redundancy in promoting structural resilience – features that are defining characteristics of multi-campus university systems (MUS), such as the University of California and University of Texas systems. Importantly, our findings show how MUS enhance regional integration by enabling resource sharing, supporting knowledge co-production, and generating network effects in human and intellectual capital that reach beyond RIS boundaries.