Regional differences in how related variety ‘works’: the case of labour mobility

The benefits of related variety on regional employment growth have become a prevailing view. However, these remain potential benefits unless channels (e.g. labour flows, inter-firm cooperation) and regional capabilities are in place to convert them into actual growth. This paper focuses on the labour mobility channel and proposes a way to measure the realized part of related variety. It demonstrates that in Sweden, core regions make ten times more use of their related variety potential via labour mobility than small, peripheral regions. Moreover, even in core and large regions only a handful of potential ties are realized. Most firms in small regions must rely on other channels to convert related variety potential into growth. Furthermore, while local labour flows between related industries are associated with higher employment growth, no evidence is found that, on average, other channels bring growth benefits in small regions. Thus, the paper argues that the role of market-mediated knowledge flow channels like labour mobility is underestimated compared to pure spillovers via unintended interactions. Consequently, it is important to go beyond assuming that the benefits of related variety are ‘in the air’ or in local ‘buzz’ and focus on specific channels at work.