Does high-speed railway promote regional innovation growth or innovation convergence?

The paper utilizes an endogenous innovation growth model including high-speed railway (HSR) fares and speeds to explain how HSR affects regional technological innovation. Difference-in-Difference (DID) regression analysis shows that HSR has significantly promoted innovation growth and innovation convergence in China, with the effect value of 14.73% and 5.91% respectively. The conclusion that HSR promotes innovation growth is still valid through endogenous treatment of instrumental variable method. Various robustness analyses show that the more stations or lines connection, the more conducive to promoting innovation growth and innovation convergence. The conclusion is still robust after different time bandwidth is set. Further analysis shows that HSR has significantly promoted the innovation development and innovation convergence within and between the three regions of eastern China, central China and western China. The innovation spillover range of innovation center cities to non-innovation cities is 300 km. In addition, it is found that cities that have not opened HSR can also benefit from the connection of HSR in neighboring cities, thus promoting innovation growth, but the impact on innovation convergence is not as significant as the direct connection of HSR. The policy enlightenment of this paper is that in the face of innovation gap and regional innovation development inequality, in the planning and construction of HSR, it is suggested to coordinate the regional layout of investment in high-speed rail construction, which is not only conducive to promoting the innovation growth of these regions, but also conducive to narrowing the regional innovation development gap. In addition, remote and backward areas should seize the opportunity of opening high-speed railways to promote regional innovative growth, instead of making high-speed railways a channel for factors such as human capital to escape.