6533b7d1fe1ef96bd125cdeb

RESEARCH PRODUCT

Bank-firm credit network in Japan. An analysis of a bipartite network

Rosario N. MantegnaHiroshi IyetomiSalvatore MiccichèHideaki AoyamaYoshi FujiwaraMauro GallegatiLuca Marotta

subject

Physics - Physics and SocietyTime FactorsFinancial networksFOS: Physical scienceslcsh:MedicineNetwork sciencePhysics and Society (physics.soc-ph)01 natural sciences010305 fluids & plasmasFOS: Economics and businessJapanTime windowsCarry (investment)Residence Characteristics0103 physical sciences010306 general physicsLocationEmpirical evidencelcsh:ScienceIndustrial organizationProbabilityStructure (mathematical logic)MultidisciplinaryEconomic sectorlcsh:RCommerceSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)econophysics networks communities banks firmsBipartite graphBond marketlcsh:QBusinessGeneral Finance (q-fin.GN)Quantitative Finance - General FinanceAlgorithmsResearch Article

description

We present an analysis of the credit market of Japan. The analysis is performed by investigating the bipartite network of banks and firms which is obtained by setting a link between a bank and a firm when a credit relationship is present in a given time window. In our investigation we focus on a community detection algorithm which is identifying communities composed by both banks and firms. We show that the clusters 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. Specifically, we obtain communities of banks and networks for each of the 32 investigated years, and we introduce a method to track the time evolution of these communities on a statistical basis. We then characterize communities by detecting the simultaneous 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 clusters of banks and firms together with a slow dynamics 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.

http://arxiv.org/pdf/1407.5429