Industrial diversification is considered crucial for economies to prosper. Recent studies have shown that regional economies tend to diversify into sectors that are related to those already present in the region. However, no study yet has investigated the impact of regional institutions. The objective of the paper is to bring together the literatures on related diversification and institutions by analyzing how formal and informal institutions influence regional diversification. Analyzing 118 European regions in the period 2004 and 2012, we find evidence that institutions matter for regions to diversify into new industries. Bridging social capital is a key driver of regional diversification, in addition to relatedness, in contrast to quality of government in regions. Bonding social capital has a negative impact in regions with a low quality of government. This suggests that regional institutions relevant for structural change in regions are predominantly informal in character rather than formal, and bridging rather than bonding.

Although the theoretical framework on agglomeration externalities and the channels through which they influence the regional economy appear well established, the empirical evidence on their magnitude and impact has been rather ambiguous and inconclusive. Applying the concepts of related and unrelated variety to an interregional European dataset and using spatial panel analysis, this paper provides critical information on the type and functioning of agglomeration externalities in relation to regional heterogeneity in knowledge intensity and innovation. We demonstrate that modeling this regional heterogeneity in a spatial panel setting is a crucial condition for identifying the positive agglomeration effects of (un)related variety on regional growth. The outcomes have substantial implications for European regional policy: We argue that policies should be both conceptually enriched and more empirically informed. JEL Classification

Through an analysis of total factor productivity for European regions using an econometric identification strategy, we find that significant impacts exist for both urban size and structure. A larger urban size positively affects regional productivity. Polycentric urban structures have no directly identified impacts on productivity. We find that an interaction between urban size and polycentricity has a negative effect, suggesting that polycentric regions are unable to substitute for the economic urbanization externalities associated with a single large city. These findings have important implications for the European Union-wide policy agenda on urban development and regional productivity.

Productivity across European regions is related to three types of networks that mediate R&D-related knowledge spillovers: trade, co-patenting and geographical proximity. Both our panel and instrumental variable estimations for European regions suggest that network relations are crucial sources of R&D spillovers, but with potentially different features. Both import and co-patenting relations affect local productivity directly, but spillovers from innovation-leading regions are effective only when they are import-mediated and when recipient regions have a solid knowledge base. From a policy perspective, this may frustrate recent European policy initiatives, such as Smart Specialization, which are designed to benefit all regions in Europe.

This article investigates the link between multinational enterprises (MNEs) and employment in their host regions by cross-fertilising the literature on MNE externalities with the emerging body of research on industrial relatedness. The link between employment and MNE presence in the same and related industries is tested for European regions. The results suggest that cross-sectoral MNE spillovers are mediated through industrial relatedness and that they are positively and significantly associated with higher employment levels, independently of input–output relations. Our results indicate that regions characterised by lower factor prices are likely to benefit the most from the presence of multinationals in terms of employment, but these benefits are concentrated in high knowledge-intensive sectors, potentially fostering inequalities within less-developed economies.