Opinion dynamics is an opinion evolution process of a group of agents, where the final
opinion distribution tends to three stable states: consensus, polarization, and fragmentation …

This review presents a general theory of financial crashes and of stock market instabilities
that his co-workers and the author have developed over the past seven years. We start by …

We use methods of random matrix theory to analyze the cross-correlation matrix C of stock
price changes of the largest 1000 US companies for the 2-year period 1994–1995. We find …

We study the distribution of fluctuations of the S&P 500 index over a time scale Δ t by
analyzing three distinct databases. Database (i) contains approximately 1 200 000 records …

Following the recently introduced concept of transfer entropy, we attempt to measure the
information flow between two financial time series, the Dow Jones and DAX stock index …

We study the statistical properties of volatility, measured by locally averaging over a time
window T, the absolute value of price changes over a short time interval Δ t. We analyze the …

We present a phenomenological study of stock price fluctuations of individual companies.
We systematically analyze two different databases covering securities from the three major …

After a short excursion from the discovery of Brownian motion to the Richardson" law of four
thirds" in turbulent diffusion, the article introduces the Lévy flight superdiffusion as a self …

This paper introduces an agent-based artificial financial market in which heterogeneous
agents trade one single asset through a realistic trading mechanism for price formation …

Entropy is originally introduced to explain the inclination of intensity of heat, pressure, and
density to gradually disappear over time. Based on the concept of entropy, the Second Law …