# The Growth of Oligarchy in a Yard-Sale Model of Asset Exchange - A Logistic Equation for Wealth Condensation

### Bruce M. Boghosian, Adrian Devitt-Lee, Hongyan Wang

#### Abstract

The addition of wealth-attained advantage (WAA) to the Yard-Sale Model (YSM) of asset exchange has been demonstrated to induce wealth condensation. In models of WAA for which the bias is a continuous function of the wealth difference of the transacting agents, the condensation arises from a second-order phase transition to a coexistence regime. In this paper, we present the first analytic time-dependent results for this model, by showing that the condensed wealth obeys a simple logistic equation in time.

#### References

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#### Paper Citation

#### in Harvard Style

Boghosian B., Devitt-Lee A. and Wang H. (2016). **The Growth of Oligarchy in a Yard-Sale Model of Asset Exchange - A Logistic Equation for Wealth Condensation** . In *Proceedings of the 1st International Conference on Complex Information Systems - Volume 1: COMPLEXIS,* ISBN 978-989-758-181-6, pages 187-193. DOI: 10.5220/0005956501870193

#### in Bibtex Style

@conference{complexis16,

author={Bruce M. Boghosian and Adrian Devitt-Lee and Hongyan Wang},

title={The Growth of Oligarchy in a Yard-Sale Model of Asset Exchange - A Logistic Equation for Wealth Condensation},

booktitle={Proceedings of the 1st International Conference on Complex Information Systems - Volume 1: COMPLEXIS,},

year={2016},

pages={187-193},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005956501870193},

isbn={978-989-758-181-6},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 1st International Conference on Complex Information Systems - Volume 1: COMPLEXIS,

TI - The Growth of Oligarchy in a Yard-Sale Model of Asset Exchange - A Logistic Equation for Wealth Condensation

SN - 978-989-758-181-6

AU - Boghosian B.

AU - Devitt-Lee A.

AU - Wang H.

PY - 2016

SP - 187

EP - 193

DO - 10.5220/0005956501870193