This paper considers business networks. Through empirical study, we show that business networks display characteristics of small-world networks and scale-free networks. In this paper, we characterize firms as sales and bankruptcy probabilities. A correlation between sales and a correlation...

The dynamics of a stock market with heterogeneous agents is discussed in the framework of a recently proposed spin model for the emergence of bubbles and crashes. We relate the log-returns of stock prices to magnetization in the model and find that it is closely related to trading volume as...

Firm dynamics on a transaction network is considered from the standpoint of econophysics, agent-based simulations, and game theory. In this model, interacting firms rationally invest in a production facility to maximize net present value. We estimate parameters used in the model through...

In this study, we attempted to determine how eigenvalues change, according to random matrix theory (RMT), in stock market data as the number of stocks comprising the correlation matrix changes. Specifically, we tested for changes in the eigenvalue properties as a function of the number and type...

The fractional Poisson process (FPP) is a counting process with independent and identically distributed inter-event times following the Mittag-Leffler distribution. This process is very useful in several fields of applied and theoretical physics including models for anomalous diffusion. Contrary...

The aim of this paper is to provide one potential theoretical explanation for questions how asset bubbles come about, why it persists, and what caused it to burst. We propose a new model of bubbles and crashes. We divide the risky assets into two classes, the bubble asset and the non-bubble...

In this chapter we investigate root causes of the recent U.S. housing bubble which has been caused a serious downturn in U.S. economic growth since autumn of 2008. We propose a simple model of housing markets in order to indicate the possible determinants of recent housing prices. Utilizing the...

The aim of this paper is to demonstrate that dynamic paths in a model of discrete choice with social interactions, which have been developed by Brock and Durlauf (1999, 2001a, 2001b, 2006), converge some self-consistent equilibrium. To this aim, we propose an asynchronous model of...

This paper provides an example in which regional business cycles may synchronize via producers’ expectations, even though there is no interregional trade, by means of a system of globally coupled, noninvertible maps. We concentrate on the dependence of the dynamics on a parameter η which...

In this paper, we quantitatively investigate the statistical properties of an ensemble of stock prices. We selected 1200 stocks traded in the Tokyo Stock Exchange and formed a statistical ensemble of daily stock prices for each trading day in the 5 year period from January 4, 1988 to December...