Subduing always defecting mutants by multiplayer reactive strategies: Non-reciprocity versus generosity

Shubhadeep Sadhukhan; Ashutosh Shukla; Sagar Chakraborty

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arXiv · 2111.04293

Subduing always defecting mutants by multiplayer reactive strategies: Non-reciprocity versus generosity

Shubhadeep Sadhukhan·Ashutosh Shukla·Sagar Chakraborty

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Abstract

A completely non-generous and reciprocal population of players can create a robust cooperating state that cannot be invaded by always defecting free riders if the interactions among players are repeated for long enough. However, strict non-generosity and strict reciprocity are ideal concepts, and may not even be desirable sometimes. Therefore, to what extent generosity or non-reciprocity can be allowed while still not be swamped by the mutants, is a natural question. In this paper, we not only ask this question but furthermore ask how generosity comparatively fares against non-reciprocity in this context. For mathematical concreteness, we work within the framework of multiplayer repeated prisoner's dilemma game with reactive strategies in a finite and an infinite population; and explore the aforementioned questions through the effects of the benefit to cost ratio, the interaction group size, and the population size.

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Shubhadeep Sadhukhan, Ashutosh Shukla, Sagar Chakraborty. 2021-11-08. Subduing always defecting mutants by multiplayer reactive strategies: Non-reciprocity versus generosity. https://arxiv.org/abs/2111.04293

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