Strategy-Proof Mechanisms for the k-Winner Selection Problem

The goal of this paper is to develop a strategy-proof (SP) mechanism for the k-winner selection problem, which finds a set of (at most) k winners among participants. Here, we assume the winners can have positive/negative externalities with each other; the gross utility of a winner not only depends on whether she wins, but also on the other winners. If the types of agents, i.e., the gross utilities of agents, are known, we can obtain a Pareto efficient (PE) allocation that maximizes the sum of the gross utilities of winners in polynomial time, assuming k is a constant. On the other hand, when the types of agents are private information, we need a mechanism that can elicit the true types of agents; it must satisfy SP. We first show that there exists no SP mechanism that is PE, individual rational (IR), and non-deficit (ND) in a general setting where we put no restrictions on possible agent types. Thus, we need to give up at least one of these desirable properties.

[1]  William Vickrey,et al.  Counterspeculation, Auctions, And Competitive Sealed Tenders , 1961 .

[2]  Tomasz P. Michalak,et al.  Combinatorial auctions with externalities , 2010, AAMAS.

[3]  Xiaotie Deng,et al.  On the Complexity of Cooperative Solution Concepts , 1994, Math. Oper. Res..

[4]  E. Maskin,et al.  The Implementation of Social Choice Rules: Some General Results on Incentive Compatibility , 1979 .

[5]  Makoto Yokoo,et al.  Keyword auction protocol for dynamically adjusting the number of advertisements , 2010, Web Intell. Agent Syst..

[6]  Ioannis Milis,et al.  The densest k-subgraph problem on clique graphs , 2007, J. Comb. Optim..

[7]  E. H. Clarke Multipart pricing of public goods , 1971 .

[8]  David C. Parkes,et al.  On Expressing Value Externalities in Position Auctions , 2011, AAAI.

[9]  Kamesh Munagala,et al.  Mechanisms and allocations with positive network externalities , 2012, EC '12.

[10]  Theodore Groves,et al.  Incentives in Teams , 1973 .

[11]  Yoav Shoham,et al.  Multiagent Systems - Algorithmic, Game-Theoretic, and Logical Foundations , 2009 .

[12]  Ilya Segal,et al.  Solutions manual for Microeconomic theory : Mas-Colell, Whinston and Green , 1997 .

[13]  Piotr Krysta,et al.  Externalities among Advertisers in Sponsored Search , 2011, SAGT.

[14]  R. Myerson Incentive Compatibility and the Bargaining Problem , 1979 .

[15]  Yehoshua Perl,et al.  Clustering and domination in perfect graphs , 1984, Discret. Appl. Math..

[16]  Uriel Feige,et al.  The Dense k -Subgraph Problem , 2001, Algorithmica.

[17]  Nima Haghpanah,et al.  Optimal auctions with positive network externalities , 2011, EC '11.