arXiv subjects

M. A. Fuentes

Publications and source records attributed to M. A. Fuentes.

4 recordsLinked to original sources

arXiv2006

Living in an Irrational Society: Wealth Distribution with Correlations between Risk and Expected Profits

Different models to study the wealth distribution in an artificial society have considered a transactional dynamics as the driving force. Those models include a risk aversion factor, but also a finite probability of favoring the poorer agent in a transaction. Here we study the case where the partners in the transaction have a previous knowledge of the winning probability and adjust their risk aversion taking this information into consideration. The results indicate that a relatively equalitarian society is obtained when the agents risk in direct proportion to their winning probabilities. However, it is the opposite case that delivers wealth distribution curves and Gini indices closer to empirical data. This indicates that, at least for this very simple model, either agents have no knowledge of their winning probabilities, either they exhibit an ``irrational'' behavior risking more than reasonable.

physics.soc-ph↗

arXiv2003

Analytic considerations in the study of spatial patterns arising from non-local interaction effects in population dynamics

Simple analytic considerations are applied to recently discovered patterns in a generalized Fisher equation for population dynamics. The generalization consists of the inclusion of non-local competition interactions among individuals. We first show how stability arguments yield a condition for pattern formation involving the ratio of the pattern wavelength and the effective diffusion length of the individuals. We develop a mode-mode coupling analysis which might be useful in shedding some light on the observed formation of small-amplitude versus large-amplitude patterns.

nlin.PS↗

arXiv2003

Non-local Interaction Effects on Pattern Formation in Population Dynamics

We consider a model for population dynamics such as for the evolution of bacterial colonies which is of the Fisher type but where the competitive interaction among individuals is non-local, and show that spatial structures with interesting features emerge. These features depend on the nature of the competitive interaction as well as on its range, specifically on the presence or absence of tails in, and the central curvature of, the influence function of the interaction.

nlin.PS↗

arXiv2001

"Fuzzy" stochastic resonance: robustness against noise tuning due to non Gaussian noises

We have analyzed the phenomenon of stochastic resonance in a system driven by non Gaussian noises. We have considered both white and colored noises. In the latter case we have obtained a consistent Markovian approximation that enables us to get quasi-analytical results for the signal-to-noise ratio. As the system departs from Gaussian behavior, our main findings are: an enhancement of the response together with a notable robustness against noise tuning. These remarkable findings are supported by extensive numerical simulations. We also discuss the relation with some experiments in sensory systems.

cond-mat.stat-mech↗