This study explores the importance of knowledge transfer for international technology diffusion by examining ethnic scientific and entrepreneurial communities in the US and their ties to their home countries. US ethnic research communities are quantified by applying an ethnic-name database to...

We model spatial clusters of similar firms. Our model highlights how agglomerative forces lead to localized, individual connections among firms, while interaction costs generate a defined distance over which attraction forces operate. Overlapping firm interactions yield agglomeration clusters...