112 citations · 529 across the 27 of their papers we have counts for
17 papers · 1 filter
Strategyproof Social Decision Schemes on Super Condorcet Domains
Felix Brand, Patrick Lederer, Sascha Tausch
One of the central economic paradigms in multi-agent systems is that agents should not be better off by acting dishonestly. In the context of collective decision-making, this axiom…
Reaching Individually Stable Coalition Structures
Felix Brandt, Martin Bullinger, Anaëlle Wilczynski
The formal study of coalition formation in multi-agent systems is typically realized in the framework of hedonic games, which originate from economic theory. The main focus of this…
Incentives in Social Decision Schemes with Pairwise Comparison Preferences
Felix Brandt, Patrick Lederer, Warut Suksompong
Social decision schemes (SDSs) map the ordinal preferences of individual voters over multiple alternatives to a probability distribution over the alternatives. In order to study th…
On the Indecisiveness of Kelly-Strategyproof Social Choice Functions
Felix Brandt, Martin Bullinger, Patrick Lederer
Social choice functions (SCFs) map the preferences of a group of agents over some set of alternatives to a non-empty subset of alternatives. The Gibbard-Satterthwaite theorem has s…
Funding Public Projects: A Case for the Nash Product Rule
Florian Brandl, Felix Brandt, Matthias Greger +3
We study a mechanism design problem where a community of agents wishes to fund public projects via voluntary monetary contributions by the community members. This serves as a model…
Fractional Hedonic Games
Haris Aziz, Florian Brandl, Felix Brandt +3
The work we present in this paper initiated the formal study of fractional hedonic games, coalition formation games in which the utility of a player is the average value he ascribe…
k-Majority Digraphs and the Hardness of Voting with a Constant Number of Voters
Georg Bachmeier, Felix Brandt, Christian Geist +4
Many hardness results in computational social choice make use of the fact that every directed graph may be induced as the pairwise majority relation of some preference profile. How…
Arrovian Aggregation of Convex Preferences
Florian Brandl, Felix Brandt
We consider social welfare functions that satisfy Arrow's classic axioms of independence of irrelevant alternatives and Pareto optimality when the outcome space is the convex hull…
Proving the Incompatibility of Efficiency and Strategyproofness via SMT Solving
Florian Brandl, Felix Brandt, Manuel Eberl +1
Two important requirements when aggregating the preferences of multiple agents are that the outcome should be economically efficient and the aggregation mechanism should not be man…
Optimal Bounds for the No-Show Paradox via SAT Solving
Felix Brandt, Christian Geist, Dominik Peters
Voting rules allow multiple agents to aggregate their preferences in order to reach joint decisions. Perhaps one of the most important desirable properties in this context is Condo…
Welfare Maximization Entices Participation
Florian Brandl, Felix Brandt, Johannes Hofbauer
We consider randomized mechanisms with optional participation. Preferences over lotteries are modeled using skew-symmetric bilinear (SSB) utility functions, a generalization of cla…
Consistent Probabilistic Social Choice
Florian Brandl, Felix Brandt, Hans Georg Seedig
Two fundamental axioms in social choice theory are consistency with respect to a variable electorate and consistency with respect to components of similar alternatives. In the cont…
An Ordinal Minimax Theorem
Felix Brandt, Markus Brill, Warut Suksompong
In the early 1950s Lloyd Shapley proposed an ordinal and set-valued solution concept for zero-sum games called \emph{weak saddle}. We show that all weak saddles of a given zero-sum…
The Computational Complexity of Random Serial Dictatorship
Haris Aziz, Felix Brandt, Markus Brill
In social choice settings with linear preferences, random dictatorship is known to be the only social decision scheme satisfying strategyproofness and ex post efficiency. When also…
Stable partitions in additively separable hedonic games
Haris Aziz, Felix Brandt, Hans Georg Seedig
An important aspect in systems of multiple autonomous agents is the exploitation of synergies via coalition formation. In this paper, we solve various open problems concerning the…
Optimal Partitions in Additively Separable Hedonic Games
Haris Aziz, Felix Brandt, Hans Georg Seedig
We conduct a computational analysis of fair and optimal partitions in additively separable hedonic games. We show that, for strict preferences, a Pareto optimal partition can be fo…
On Iterated Dominance, Matrix Elimination, and Matched Paths
Felix Brandt, Felix Fischer, Markus Holzer
We study computational problems arising from the iterated removal of weakly dominated actions in anonymous games. Our main result shows that it is NP-complete to decide whether an…