{ "id": "2303.15386", "version": "v1", "published": "2023-03-27T16:59:36.000Z", "updated": "2023-03-27T16:59:36.000Z", "title": "Robustness of Dynamics in Games: A Contraction Mapping Decomposition Approach", "authors": [ "Sina Arefizadeh", "Sadegh Arefizadeh", "S. Rasoul Etesami", "Sadegh Bolouki" ], "categories": [ "cs.GT" ], "abstract": "A systematic framework for analyzing dynamical attributes of games has not been well-studied except for the special class of potential or near-potential games. In particular, the existing results have shortcomings in determining the asymptotic behavior of a given dynamic in a designated game. Although there is a large body literature on developing convergent dynamics to the Nash equilibrium (NE) of a game, in general, the asymptotic behavior of an underlying dynamic may not be even close to a NE. In this paper, we initiate a new direction towards game dynamics by studying the fundamental properties of the map of dynamics in games. To this aim, we first decompose the map of a given dynamic into contractive and non-contractive parts and then explore the asymptotic behavior of those dynamics using the proximity of such decomposition to contraction mappings. In particular, we analyze the non-contractive behavior for better/best response dynamics in discrete-action space sequential/repeated games and show that the non-contractive part of those dynamics is well-behaved in a certain sense. That allows us to estimate the asymptotic behavior of such dynamics using a neighborhood around the fixed point of their contractive part proxy. Finally, we demonstrate the practicality of our framework via an example from duopoly Cournot games.", "revisions": [ { "version": "v1", "updated": "2023-03-27T16:59:36.000Z" } ], "analyses": { "keywords": [ "contraction mapping decomposition approach", "asymptotic behavior", "robustness", "better/best response dynamics", "discrete-action space sequential/repeated games" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }