Evolution of economic entities under heterogeneous political/environmental conditions within a Bak-Sneppen-like dynamics

A model for economic behavior, under heterogeneous spatial economic conditions is developed. The role of selection pressure in a Bak-Sneppen-like dynamics with entity diffusion on a lattice is studied by Monte-Carlo simulation taking into account business rule(s), like enterprise - enterprise short range location "interaction"(s), business plan(s) through spin-offs or merging and enterprise survival evolution law(s). It is numerically found that the model leads to a sort of phase transition for the fitness gap as a function of the selection pressure.Comment: 6 figures. to be published in Physica

An attempt to observe economy globalization: the cross correlation distance evolution of the top 19 GDP's

Economy correlations between the 19 richest countries are investigated through their Gross Domestic Product increments. A distance is defined between increment correlation matrix elements and their evolution studied as a function of time and time window size. Unidirectional and Bidirectional Minimal Length Paths are generated and analyzed for different time windows. A sort of critical correlation time window is found indicating a transition for best observations. The mean length path decreases with time, indicating stronger correlations. A new method for estimating a realistic minimal time window to observe correlations and deduce macroeconomy conclusions from such features is thus suggested.Comment: to be published in the Dyses05 proceedings, in Int. J. Mod Phys C 15 pages, 5 figures, 1 tabl

Fiat Money and the Natural Scale of Government

The competitive market structure of a decentralized economy is converted into a self-policing system treating the bureaucracy and enforcement of the legal system endogenously. In particular we consider money systems as constructs to make agents' economic strategies predictable from knowledge of their preferences and endowments, and thus to support coordinated resource production and distribution from independent decision making. Diverse rule systems can accomplish this, and we construct minimal strategic market games representing government-issued fiat money and ideal commodity money as two cases. We endogenize the provision of money and rules for its use as productive activities within the society, and consider the problem of transition from generalist to specialist production of subsistence goods as one requiring economic coordination under the support of a money system to be solved. The scarce resource in a society is labor limited by its ability to coordinate (specifically, calling for the expenditure of time and effort on communication, computation, and control), which must be diverted from primary production either to maintain coordinated group activity, or to provide the institutional services supporting decentralized trade. Social optima are solutions in which the reduced costs of individual decision making against rules (relative to maintenance of coalitions) are larger than the costs of the institutions providing the rules, and in which the costs of the institutions are less than the gains from the trade they enable to take place.Bureaucracy, Contract enforcement, Taxes, Money

A Model for Scaling in Firms' Size and Growth Rate Distribution

We introduce a simple agent-based model which allows us to analyze three stylized facts: a fat-tailed size distribution of companies, a `tent-shaped' growth rate distribution, the scaling relation of the growth rate variance with firm size, and the causality between them. This is achieved under the simple hypothesis that firms compete for a scarce quantity (either aggregate demand or workforce) which is allocated probabilistically. The model allows us to relate size and growth rate distributions. We compare the results of our model to simulations with other scaling relationships, and to similar models and relate it to existing theory. Effects arising from binning data are discussed.Comment: accepted for publication in Physica