Connectivity correlations in three topological spaces of urban bus-transport networks in China

In this paper, an empirical investigation is presented, whichfocuses on unveiling the universality of connectivity correlationsin three spaces (the route space, the stop geographical space andbus-transferring space) of urban bus-transport networks (BTNs) infour major cities of China. The underlying features of theconnectivity correlations are shown in two statistical ways. One isthe correlation between the (weighted) average degree of all thenearest neighbouring vertices with degree $k$, ($K^w_{nn}(k)$)$K_{nn}(k)$, and $k$, and the other is the correlations between theassortativity coefficient $r$ and, respectively, the network size$N$, the network diameter $D$, the averaged clustering coefficient$C$, and the averaged distance $lan lran$. The obtained resultsshow qualitatively the same connectivity correlations of all theconsidered cities under all the three spaces.