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arXiv · 2402.08541

Continuous-Time Best-Response and Related Dynamics in Tullock Contests with Convex Costs

Edith Elkind·Abheek Ghosh·Paul W. Goldberg
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Abstract

Tullock contests model real-life scenarios that range from competition among proof-of-work blockchain miners to rent-seeking and lobbying activities. We show that continuous-time best-response dynamics in Tullock contests with convex costs converges to the unique equilibrium using Lyapunov-style arguments. We then use this result to provide an algorithm for computing an approximate equilibrium. We also establish convergence of related discrete-time dynamics, e.g., when the agents best-respond to the empirical average action of other agents. These results indicate that the equilibrium is a reliable predictor of the agents' behavior in these games.

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Edith Elkind, Abheek Ghosh, Paul W. Goldberg. 2024-02-13. Continuous-Time Best-Response and Related Dynamics in Tullock Contests with Convex Costs. https://arxiv.org/abs/2402.08541

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