We analyze a database comprising quarterly sales of 55624 pharmaceutical products commercialized by 3939 pharmaceutical firms in the period 1992-2001. We study the probability density function (PDF) of growth in firms and product sales and find that the width of the PDF of growth decays with the...

We present a preferential attachment growth model to obtain the distribution P(K) of number of units K in the classes which may represent business firms or other socio-economic entities. We found that P(K) is described in its central part by a power law with an exponent amp;#966; = 2+b/(1amp;#8722;b)...

We introduce a model of proportional growth to explain the distribution P(g) of business firm growth rates. The model predicts that P(g) is Laplace in the central part and depicts an asymptotic power - law behavior in the tails with an exponent z = 3. Because of data limitations, previous...

In this paper, we introduced a simple money exchange model including agents with minimal intelligence and one representative commercial bank as a showcase for the money creation process in the modern economy. Using this econophysics model with basic behavioral assumptions, we can identify the...

Classic studies of the probability density of price fluctuations g for stocks and foreign exchanges of several highly developed economies have been interpreted using a power-law probability density function P(g) ∼ g−( 1) with exponent values 2, which are outside the L´evy-stable regime 0 ...