High-speed rails and knowledge productivity: A global perspective

This study finds empirical macro-economic evidence for the effect of high-speed rails (HSRs) on national innovation through the analyses of 59 highand upper-middle-income countries. Knowledge productivity (KP) is assumed to be represented by annual patent applications per million capita. The associations between HSR development and KP are analyzed with three methods: (1) estimation of KP function using 10-year panel data, covering 14 countries with HSRs; (2) estimation of average treatment effect using difference-in-differences analysis for a treatment group of 15 and a control group of 44 countries; and (3) estimation of average treatment effect using matching techniques for a dataset covering 29 countries, of which 10 received treatment. The results of all three analyses covering about 40 years of HSRs' history, robustly suggest that HSR development can have positive externalities on KP both in the short and long runs. In addition, it is found that the HSRs' impacts on countries with upper-middle income and countries with high urban population growth are larger than other countries. They suggest that HSR development can be a part of national innovation policy and that upper-middleincome countries, highly urbanizing countries, and countries with insufficient inter-regional transportation systems can have advantages in HSR introduction for promoting knowledge productivity.