Page 370 - 360.revista de Alta Velocidad - Nº 6

Yang, Haoran. Dobruszkes, Frédéric. Wang, Jiao’e. Dijst, Martin.

HSR Airline

Figure 2. The distribution of HSR and airline cities 4

It is worth noting that airline and HSR travel is arguably not representative of all medium- and
longdistance travel within China. Indeed, there is clear evidence that the poor and even a part
of the middle class have much less access to airlines and HSRs due to relative high monetary
travel cost than conventional railways (Delaplace and Dobruszkes, 2015; Wang et al., 2013). For
instance, migrants living in cities favour conventional (lower-speed) trains to visit other cities
notably because it is much cheaper (Liu and Kesteloot, 2015). In addition, various cities are
neither served by HSR services nor by air services. Therefore, our research does not capture
the full set of functional interactions between cities. Instead, our research is focused on urban
systems as reflected by both HSR and air passenger flows, which favour mobilities of the upper
social-occupational groups (business activities, government officials, premium tourism or VFR
(visiting friends and relatives) travel, etc).

3.2 Analytical framework

3.2.1 Measures of the city centrality and link connectivity

To identify the structural characteristics of the urban system as manifested by airline and HSR
passenger flows, it is necessary to understand the urban hierarchical structure based on city
centrality and connectivity rankings in the transportation network. We measure configuration
of the urban systems by adapting the framework presented in Limtanakool et al. ( 2007) and
Van Nuffel et al. (2010) in which two strength indices (namely, city strength and link strength)
are used to measure the city centrality and link connectivity.

4 The division between the west, middle and east is based on NBSC (2011).

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