Detection of Comoving Groups in a Financial Market
We reported a correlation structure hidden in the Tokyo Stock Exchange (TSE) market at KES-IDT2011. By regarding the TSE market as a network (stocks and correlation coefficients correspond to nodes and weights of links between nodes, respectively) and minimizing the Frustration among nodes, the stocks were decomposed into four comoving groups forming communities. Three of them are strongly anticorrelated to each other, and the remainder is comparatively neutral to the rest of the communities. In this paper we further extend the previous work to detect tightly-coupled groups within the communities; “Hamiltonian” is used instead of the Frustration. The Hamiltonian has two parameters which control degree of strength for correlations to be extracted. It is found that six sectors (Electric Appliance, Banks, Electric Power & Supply, Information & Communication, Securities & Commodity Futures, and Insurance) form strong cores in the communities.
Unable to display preview. Download preview PDF.