Trains of Thought: High-Speed Rail and Innovation in China

This paper explores the effect of the High Speed Rail (HSR) network expansion on local innovation in China during the period 2008-2016. Using exogenous variation arising from a novel instrument - courier’s stations during the Ming dynasty, we find solid evidence that the opening of a HSR station increases cities’ innovation activity. We also explore the role of inter-city technology diffusion as being behind the surge of local innovation. To do it, we compute least-cost paths between city-pairs, over time, based on the opening and speed of each HSR line, and obtain that an increase in a city’s connectivity to other cities specialized in a specific technological field, through the HSR network, increases the probability for the city to specialize in that same technological field. We interpret it as evidence of knowledge diffusion.