We study the subway network system for four cities, i.e., Seoul, Tokyo, Boston and Beijing, by
using the global and local efficiencies. It is found that the Seoul subway network has a smaller
global and local efficiencies than that of Tokyo. We sugg...
We study the subway network system for four cities, i.e., Seoul, Tokyo, Boston and Beijing, by
using the global and local efficiencies. It is found that the Seoul subway network has a smaller
global and local efficiencies than that of Tokyo. We suggest that the Tokyo subway system is
better for an overall distance trip but is not weaker regarding incidents of disconnection. It is
also validated for the four subway networks that the global efficiency is inversely proportional to
the characteristic length. The Boston and Beijing local efficiencies, that depend on the number of
triangular-formed topographic units, are very low and zero, respectively, and this means that these
are somewhat deficiently round about routes. Especially, on comparing the characteristic length
and the clustering coefficient, the global and local efficiencies seem to be more useful when both
the concept of connectivity and length are needed.