Proximity and the evolving knowledge polycentricity of megalopolitan science: Evidence from China's Guangdong-Hong Kong-Macao Greater Bay Area, 1990–2016.

Despite the two key defining features of megalopolises as incubators and hinges in a globalising knowledge economy, how intercity knowledge flows could shape the polycentric structure of the science system of a megalopolis has only gained popularity in recent years. This study focuses on measuring and explaining the evolving knowledge polycentricity of the science system of China's Greater Bay Area (GBA) megalopolis during the 1990–2016 period. Our empirical results are generally robust when we adopt different measurement approaches and draw upon different publication databases. Overall, the degrees of knowledge polycentricity at different geographical scales have been generally increasing during the study period, though with some fluctuations. In addition, the degree of knowledge polycentricity becomes smaller at higher geographical scales. The mechanisms behind the evolving knowledge polycentricity have been further investigated from the proximity perspective. The increasing geographical proximity, institutional proximity and social proximity between cities within and beyond the GBA megalopolis have contributed to the strengthening knowledge polycentricity of its science system at different geographical scales. [ABSTRACT FROM AUTHOR]