Graph theoretical analysis of the Chinese high-speed rail network over time

In this paper, we examine the development of the Chinese high-speed rail (HSR) network over the period 2003-2014. Our methodology relies on network analysis to identify changes over time in HSR network accessibility measured by node degree, strength, closeness, and betweenness. We show that sub-networks connecting regional centres with second-tier cities are fast built. Once such sub-networks are mostly established, they are also connected with each other. Moreover, a simultaneous rather than a sequential schedule for multiple HSR segments is at place at any particular time. Finally, we show that the HSR network expands all the lower-elevation, more populous and prosperous regions. Although some clusters are critical politically, HSR network development is still mainly driven by economic factors, which is reflected from the fact that nodes in the more economically vibrant regions present a higher number of routes passing through and higher service quality (i.e., lower travel time). Finally, in order to illustrate the uniqueness of the Chinese HSR development pattern, we briefly discuss and compare the HSR development in other Asian markets, notably Taiwan, South Korea and Japan.