Research collaboration beyond the boundary: Evidence from university patents in China
利用中国高铁开通作为准自然实验，发现高铁显著提升了大学与企业间的合作专利数量和质量，并帮助大学跨越地理边界寻找更优质的研究伙伴。
Abstract Geographical distance constitutes friction in searching for research collaborators. Taking advantage of a quasinatural experiment featured by High‐Speed Railway (HSR) lines in China, this paper employs the difference‐in‐differences model to identify the causal impact of a substantial improvement in the intercity transportation infrastructure on collaborative innovation across cities. The data pertain to a universe of patent applications filed by Chinese universities and their citations. We find that HSR contributes to a substantial increase in the innovation quantity and quality of collaborative patenting innovation between universities and corporates. It contributes to industry collaboration by utilizing university academic disciplines in the related technology fields. Lastly, HSR facilitates universities to search for new research partners with better quality beyond the geographical boundary.