Under the Kyoto Protocol, Clean Development Mechanism (CDM) is expected to facilitate the North-South knowledge spillovers for climate-friendly technologies. This paper examines the effects of this voluntary international climate cooperation on firm innovation and knowledge spillovers through...

Geographical distance constitutes friction of searching research collaborators. Taking advantage of a quasi-natural experiment featured by recently connected High-Speed Railway (HSR) lines in China, this paper seeks to identify the impact of a substantial improvement in intercity transportation...