Significant differences in the evolution of firm size distribution for various industries in the United States have been revealed and documented. For theoretical considerations, this finding puts major constraints on the modelling of firm growth. For practical purposes, the observed differences...

This work presents a simple method for calculating deviations regarding city size and the size which would correspond to it with a Pareto exponent equal to one unit (Zipf’s Law). Recent works show that when considering the entire sample without size restrictions, the estimated Pareto exponent...

Standard risk metrics tend to underestimate the true risks of hedge funds becauseof serial correlation in the reported returns. Getmansky et al. (2004) derive mean,variance, Sharpe ratio, and beta formulae adjusted for serial correlation. Followingtheir lead, adjusted downside and global...

Using a comprehensive international trade data set we investigate empirical regularities (known as Zipf’s Law or the rank-size rule) for the distribution of the interaction between countries as measured by revealed comparative advantage. Using the recently developed estimator by Gabaix and...

It is commonly found that distributions that seem to be lognormal over a broad range change to a power-law (Pareto) distribution for the last few percentiles. The distributions of species abundance, income and wealth as well as file, city and firm sizes are examples with this structure. We...

We provide a detailed analysis of a generalized proportional growth model (GPGM) of innovation and corporate dynamics that encompasses the Gibrat’s Law of Proportionate Effect and the Simon growth process as particular instances. The predictions of the model are derived in terms of (i) firm...

Standard risk metrics tend to underestimate the true risks of hedge funds because of serial correlation in the reported returns. Getmansky, Lo, and Makarov(2004) derive mean, variance, Sharpe ratio, and beta formulae adjusted for serial correlation. Following their lead, we derive adjusted...

We provide a detailed analysis of a model of innovation and corporate dynamics that encompasses the Gibrat's Law of Proportionate Effect and the Simon growth process as particular instances. The predictions of the model are derived in terms of (i) firm size distribution, (ii) the distribution of...

This paper analyses the distribution of the classical t-ratio statistic from distributions with no finite moments and shows how classical testing is affected. Some surprising results are obtained in terms of bimodality vs. the usual unimodality of the standard studentized t-distribution...

When a very top group of the income distribution, infinitesimal in numbers, owns a finite share S of total income, the Gini coefficient G can be approximated by G*(1 - S) + S, where G* is the Gini coefficient for the rest of the population. We provide a simple formal proof for this expression,...