Title
The Price of Optimum: Complexity and Approximation for a Matching Game
Abstract
This paper deals with a matching game in which the nodes of a simple graph are independent agents who try to form pairs. If we let the agents make their decision without any central control then a possible outcome is a Nash equilibrium, that is a situation in which no unmatched player can change his strategy and find a partner. However, there can be a big difference between two possible outcomes of the same instance, in terms of number of matched nodes. A possible solution is to force all the nodes to follow a centrally computed maximum matching but it can be difficult to implement this approach. This article proposes a tradeoff between the total absence and the full presence of a central control. Concretely, we study the optimization problem where the action of a minimum number of agents is centrally fixed and any possible equilibrium of the modified game must be a maximum matching. In algorithmic game theory, this approach is known as the price of optimum of a game. For the price of optimum of the matching game, deciding whether a solution is feasible is not straightforward, but we prove that it can be done in polynomial time. In addition, the problem is shown APX-hard, since its restriction to graphs admitting a perfect matching is equivalent, from the approximability point of view, to vertex cover. Finally we prove that this problem admits a polynomial 6-approximation algorithm in general graphs.
Year
DOI
Venue
2017
10.1007/s00453-015-0108-5
Algorithmica
Keywords
Field
DocType
Approximation algorithm,Srategic game,Complexity,Price of Anarchy,Price of optimum,Stackelberg strategy
Minimax,Combinatorics,Mathematical optimization,Strategy,Algorithmic game theory,Repeated game,Normal-form game,Sequential game,Game tree,Mathematics,Extensive-form game
Journal
Volume
Issue
ISSN
77
3
0178-4617
Citations 
PageRank 
References 
1
0.35
13
Authors
3
Name
Order
Citations
PageRank
Bruno Escoffier143037.32
Laurent Gourvès224130.97
Jérôme Monnot351255.74