An analysis of geographical agglomeration and modularized industrial networks in a regional cluster: A case study at Yamagata prefecture in Japan

In a regional innovation system, a dense inter-organizational network within the region is recognized as a key factor in enhancing knowledge diffusion, regional learning, and effective resource transfers. Therefore, understanding the network structure and physical proximity of organizations is essential. In this paper, we investigated the industrial structure of Yamagata prefecture in Japan as a case study. Because Yamagata is a representative industrial region, the analysis can also provide an insight into other industrial regions. Initially, we investigated the geographical dispersion of firms and found them to be agglomerated along Route 13 and the Tohoku Shinkansen railroad, indicating that infrastructures for transportation still have a decisive role in terms of site location. Subsequently, we analyzed the modular structure of the inter-firm network. The results showed that hub firms construct a different type of network and play different roles within the inter-firm network, reflecting their strategic choice. The results also showed that there is a tendency for firms to transact with those in close proximity, and that firm location is also affected by the location of the hub firm in the module in addition to the infrastructures.