Distribution of extinction sizes constructed from original fossil records exhibits not a single, but a double power-law, with tail exponents being roughly the same in different scales, i.e., for species, families and orders. Moreover, time correlations of extinction sizes decrease with a...

We demonstrate how the basic ideas of the fractal and the heterogeneous market hypotheses lead to a rigorous mathematical model, which can be used to solve the problem of characterizing the distribution of price changes corresponding to the empirical scaling law of volatility for high-frequency...

The conditionally exponential decay (CED) model is used to explain the scaling laws observed in financial data. This approach enables us to identify the distributions of currency exchange rate or economic indices returns (changes) corresponding to the empirical scaling laws. This is illustrated...

We use the Conditionally Exponential Decay (CED) model to explain the scaling behavior in currency exchange (FX) rates. This approach enables us not only to show that FX returns satisfy scaling with an exponent qualitatively different from that of a random walk, but also to identify the...

The Conditionally Exponential Decay (CED) model is used to explain the scaling laws observed in financial data. This approach enables us to identify the distributions of currency exchange rate or economic indices returns (changes) corresponding to the empirical scaling laws. This is illustrated...

We use the Conditionally Exponential Decay (CED) model to explain the scaling behavior in currency exchange (FX) rates. This approach enables us not only to show that FX returns satisfy scaling with an exponent qualitatively different from that of a random walk, but also to identify the...

Typical data sets employed by economists and financial analysts do not exceed a few hundred or thousand observations per series. However, in the last decade data sets containing tick-by-tick observations have become available. The studies of these data have turned up new and interesting facts...