eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
18
10.4230/DagSemProc.10101.1
article
10101 Abstracts Collection – Computational Foundations of Social Choice
Brandt, Felix
Conitzer, Vincent
Hemaspaandra, Lane A.
Laslier, Jean-Francois
Zwicker, William S.
From March 7 to March 12, 2010, the Dagstuhl Seminar 10101
``Computational Foundations of Social Choice '' was held in Schloss Dagstuhl~--~Leibniz Center for Informatics.
During the seminar, several participants presented their current
research, and ongoing work and open problems were discussed. Abstracts of
the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section
describes the seminar topics and goals in general.
Links to extended abstracts or full papers are provided, if available.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.1/DagSemProc.10101.1.pdf
Social Choice Theory
Voting
Fair Division
Algorithms
Computational Complexity
Multiagent Systems
eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
2
10.4230/DagSemProc.10101.2
article
10101 Executive Summary – Computational Foundations of Social Choice
Brandt, Felix
Conitzer, Vincent
Hemaspaandra, Lane A.
Laslier, Jean-Francois
Zwicker, William S.
This seminar addressed some of the key issues in computational social choice, a novel interdisciplinary field of study at the interface of social choice theory and computer science. Computational social choice is concerned with the application of computational techniques to the study of social choice mechanisms, such as voting rules and fair division protocols, as well as with the integration of social choice paradigms into computing. The seminar brought together many of the most active researchers in the field and focussed the research community currently forming around these important and exciting topics.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.2/DagSemProc.10101.2.pdf
Social Choice Theory
Voting
Fair Division
Algorithms
Computational Complexity
Multiagent Systems
eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
4
10.4230/DagSemProc.10101.3
article
False-name-Proof Combinatorial Auction Mechanisms
Yokoo, Makoto
In Internet auctions, it is easy for a bidder to submit multiple bids
under multiple identifiers (e.g., multiple e-mail addresses).
If only one good is sold, a bidder cannot make any additional profit by using multiple bids. However, in combinatorial auctions, where multiple
goods are sold simultaneously, submitting multiple bids under fictitious names can be profitable. A bid made under a fictitious name is called a {em false-name bid}. In this talk, I describe the summary of existing works and open problems
on false-name bids.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.3/DagSemProc.10101.3.pdf
Combinatorial auctions
mechanism design
false-name bids
eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
12
10.4230/DagSemProc.10101.4
article
Manipulability of Single Transferable Vote
Walsh, Toby
For many voting rules, it is NP-hard to compute a successful manipulation.
However, NP-hardness only bounds the worst-case complexity. Recent
theoretical results suggest that manipulation may often be easy in practice. We
study empirically the cost of manipulating the single transferable vote (STV) rule. This was one of the first rules shown to be NP-hard to manipulate. It also appears to be one of the harder rules to manipulate since it involves multiple rounds and since, unlike many other rules, it is NP-hard for a single agent to manipulate without weights on the votes or uncertainty about how the other agents have voted. In almost every election in our experiments, it was easy to compute how a single agent could manipulate the election or to prove that manipulation by a single agent was impossible. It remains an interesting open question if manipulation by a coalition of agents is hard to compute in practice.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.4/DagSemProc.10101.4.pdf
Computational social choice
manipulability
STV voting
NP-hardness
eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
6
10.4230/DagSemProc.10101.5
article
Nonmanipulable Selections from a Tournament
Altman, Alon
Procaccia, Ariel D.
Tennenholtz, Moshe
A tournament is a binary dominance relation on a set of alternatives. Tournaments arise in many contexts that are relevant to AI, most notably in voting (as a method to aggregate the preferences of agents). There are many works that deal with choice rules that select a desirable alternative from a tournament, but very few of them deal directly with incentive issues, despite the fact that game-theoretic considerations are crucial with respect to systems populated by selfish agents.
We deal with the problem of the manipulation of choice rules by considering two types of manipulation. We say that a choice rule is emph{monotonic} if an alternative cannot get itself selected by losing on purpose, and emph{pairwise nonmanipulable} if a pair of alternatives cannot make one of them the winner by reversing the outcome of the match between them. Our main result is a combinatorial construction of a choice rule that is monotonic, pairwise nonmanipulable, and onto the set of alternatives, for any number of alternatives besides three.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.5/DagSemProc.10101.5.pdf
Tournament
manipulation
eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Dagstuhl Seminar Proceedings
1862-4405
2010-05-20
10101
1
14
10.4230/DagSemProc.10101.6
article
On the stability of a scoring rules set under the IAC
Merlin, Vincent
Diss, Mostapha
Louichi, Ahmed
Smaoui, Hatem
A society facing a choice problem has also to choose the voting rule itself from a set of different possible voting rules. In such situations, the consequentialism property allows us to induce voters' preferences on voting rules from preferences over alternatives. A voting rule employed to resolve the society's choice problem is self-selective if it chooses itself when it
is also used in choosing the voting rule. A voting rules set is said to be stable if it contains at least one self-selective voting rule at each profile of preferences on voting rules. We consider in this paper a society which will make a choice from a set constituted by three alternatives {a, b, c} and a set of the three well-known scoring voting rules {Borda, Plurality, Antiplurality}.
Under the Impartial Anonymous Culture assumption (IAC), we will derive a probability for the stability of this triplet of voting rules. We use Ehrhart polynomials in order to solve our problems. This method counts the number of lattice points inside a convex bounded polyhedron (polytope). We discuss briefly recent algorithmic solutions to this method and use
it to determine the probability of stabillity of {Borda, Plurality, Antiplurality} set.
https://drops.dagstuhl.de/storage/16dagstuhl-seminar-proceedings/dsp-vol10101/DagSemProc.10101.6/DagSemProc.10101.6.pdf
Self-selectivity
Stability
Consequentialism
Ehrhart polynomials