Bank-firm credit network in Japan: an analysis of a bipartite network.
We investigate the networked nature of the Japanese credit market. Our investigation is performed with tools of network science. In our investigation we perform community detection with an algorithm which is identifying communities composed of both banks and firms. We show that the communities obtained by directly working on the bipartite network carry information about the networked nature of the Japanese credit market. Our analysis is performed for each calendar year during the time period from 1980 to 2011. To investigate the time evolution of the networked structure of the credit market we introduce a new statistical method to track the time evolution of detected communities. We then characterize the time evolution of communities by detecting for each time evolving set of communities the over-expression of attributes of firms and banks. Specifically, we consider as attributes the economic sector and the geographical location of firms and the type of banks. In our 32-year-long analysis we detect a persistence of the over-expression of attributes of communities of banks and firms together with a slow dynamic of changes from some specific attributes to new ones. Our empirical observations show that the credit market in Japan is a networked market where the type of banks, geographical location of firms and banks, and economic sector of the firm play a role in shaping the credit relationships between banks and firms.
Dipartimento di Fisica e Chimica, Università di Palermo, Palermo, Italy.
Luca
L
Marotta
Dipartimento di Fisica e Chimica, Università di Palermo, Palermo, Italy.
Salvatore
S
Miccichè
Graduate School of Simulation Studies, The University of Hyogo, Kobe, Japan.
Yoshi
Y
Fujiwara
Department of Mathematics, Niigata University, Niigata, Japan.
Hiroshi
H
Iyetomi
Graduate School of Sciences, Kyoto University, Kyoto, Japan.
Hideaki
H
Aoyama
Dipartimento di Scienze Economiche e Sociali, Università Politecnica delle Marche, Ancona, Italy.
Mauro
M
Gallegati
Dipartimento di Fisica e Chimica, Università di Palermo, Palermo, Italy; Center for Network Science and Department of Economics, Central European University, Budapest, Hungary.
Rosario N
RN
Mantegna
D000465:Algorithms; D003132:Commerce; D007564:Japan; D011336:Probability; D012111:Residence Characteristics; D013997:Time Factors