Spatial Characteristics of Joint Application Networks in Japanese Patents

TL;DR

This paper analyzes the spatial structure of patent collaboration networks in Japan, revealing power-law degree distribution, hierarchical clustering, and regional link patterns that influence innovation dynamics.

Contribution

It provides new insights into the spatial and structural characteristics of Japanese patent networks, highlighting the importance of regional proximity and existing links in collaborative innovation.

Findings

Degree distribution follows a power law.

Hierarchical structure with negative clustering coefficient correlation.

Regional proximity influences link formation.

Abstract

Technological innovation has extensively been studied to make firms sustainable and more competitive. Within this context, the most important recent issue has been the dynamics of collaborative innovation among firms. We therefore investigated a patent network, especially focusing on its spatial characteristics. The results can be summarized as follows. (1) The degree distribution in a patent network follows a power law. A firm can then be connected to many firms via hubs connected to the firm. (2) The neighbors' average degree has a null correlation, but the clustering coefficient has a negative correlation. The latter means that there is a hierarchical structure and bridging different modules may shorten the paths between the nodes in them. (3) The distance of links not only indicates the regional accumulations of firms, but the importance of time it takes to travel, which plays a key role in creating links. (4) The ratio of internal links in cities indicates that we have to consider the existing links firms have to facilitate the creation of new links.