Luis Cabral, Zhu Wang and Daniel Yi Xu
Taking the early U.S. automobile industry as an example, we evaluate four competing hypotheses on regional industry agglomeration: intra-industry local externalities, inter-industry local externalities, employee spinouts, and location fixed-effects. Our findings suggest that inter-industry spillovers, particularly the development of the carriage and wagon industry, play an important role. Spinouts play a secondary role and work as a special type of intra-industry spillovers. The presence of other firms in the same industry has a negligible (or even negative) effect. Finally, local inputs account for some agglomeration in the short run, but the effects are much more profound in the long run.
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