The role of intra- and inter-regional relatedness and unrelatedness for the geography of breakthrough technological innovation: evidence from the US
研究了区域内和区域间的技术相关性与非相关性如何影响突破性技术创新的出现，利用美国1976-2015年专利数据发现两者均有贡献，且区域内相关性可增强其他类型的作用。
Not all innovations are alike. Breakthrough technological innovations have a greater impact on regional development and are a key topic in economic geography. However, most studies focus on intra-regional factors, with little attention given to inter-regional perspectives. To address this, we extend the concepts of relatedness and unrelatedness density from the intra- to the inter-regional scale. Using US patent data from the period 1976–2015, we find that both intra-regional (un)relatedness density and inter-regional (un)relatedness density contribute to the emergence of breakthrough technological innovations in regions. Moreover, intra-regional relatedness density can reinforce the role of other types of (un)relatedness density in breakthrough technological innovations.