78 citations · 145 across the 20 of their papers we have counts for
22 papers
Selecting Representative Bodies: An Axiomatic View
Manon Revel, Niclas Boehmer, Rachael Colley +3
As the world's democratic institutions are challenged by dissatisfied citizens, political scientists and also computer scientists have proposed and analyzed various (innovative) me…
Robust and Verifiable Proportionality Axioms for Multiwinner Voting
Markus Brill, Jannik Peters
When selecting a subset of candidates (a so-called committee) based on the preferences of voters, proportional representation is often a major desideratum. When going beyond simpli…
Spatial Voting with Incomplete Voter Information
Aviram Imber, Jonas Israel, Markus Brill +2
We consider spatial voting where candidates are located in the Euclidean -dimensional space, and each voter ranks candidates based on their distance from the voter's ideal point…
Proportionality in Approval-Based Participatory Budgeting
Markus Brill, Stefan Forster, Martin Lackner +2
The ability to measure the satisfaction of (groups of) voters is a crucial prerequisite for formulating proportionality axioms in approval-based participatory budgeting elections.…
Liquid Democracy with Ranked Delegations
Markus Brill, Théo Delemazure, Anne-Marie George +2
Liquid democracy is a novel paradigm for collective decision-making that gives agents the choice between casting a direct vote or delegating their vote to another agent. We conside…
Individual Representation in Approval-Based Committee Voting
Markus Brill, Jonas Israel, Evi Micha +1
When selecting multiple candidates based on approval preferences of agents, the proportional representation of agents' opinions is an important and well-studied desideratum. Existi…
Dynamic Proportional Rankings
Jonas Israel, Markus Brill
Proportional ranking rules aggregate approval-style preferences of agents into a collective ranking such that groups of agents with similar preferences are adequately represented.…
Computing Possible and Necessary Equilibrium Actions (and Bipartisan Set Winners)
Markus Brill, Rupert Freeman, Vincent Conitzer
In many multiagent environments, a designer has some, but limited control over the game being played. In this paper, we formalize this by considering incompletely specified games,…
Approval-Based Committee Voting under Incomplete Information
Aviram Imber, Jonas Israel, Markus Brill +1
We investigate approval-based committee voting with incomplete information about the approval preferences of voters. We consider several models of incompleteness where each voter p…
Selecting Matchings via Multiwinner Voting: How Structure Defeats a Large Candidate Space
Niclas Boehmer, Markus Brill, Ulrike Schmidt-Kraepelin
Given a set of agents with approval preferences over each other, we study the task of finding matchings fairly representing everyone's preferences. We model the problem as an a…
Phragmén's Voting Methods and Justified Representation
Markus Brill, Rupert Freeman, Svante Janson +1
In the late 19th century, Swedish mathematician Lars Edvard Phragmén proposed a load-balancing approach for selecting committees based on approval ballots. We consider three commit…
Margin of Victory in Tournaments: Structural and Experimental Results
Markus Brill, Ulrike Schmidt-Kraepelin, Warut Suksompong
Tournament solutions are standard tools for identifying winners based on pairwise comparisons between competing alternatives. The recently studied notion of margin of victory (MoV)…
On the Structure of Stable Tournament Solutions
Felix Brandt, Markus Brill, Hans Georg Seedig +1
A fundamental property of choice functions is stability, which, loosely speaking, prescribes that choice sets are invariant under adding and removing unchosen alternatives. We prov…
Refining Tournament Solutions via Margin of Victory
Markus Brill, Ulrike Schmidt-Kraepelin, Warut Suksompong
Tournament solutions are frequently used to select winners from a set of alternatives based on pairwise comparisons between alternatives. Prior work has shown that several common t…
Approval-Based Apportionment
Markus Brill, Paul Gölz, Dominik Peters +2
In the apportionment problem, a fixed number of seats must be distributed among parties in proportion to the number of voters supporting each party. We study a generalization of th…
Exact Mean Computation in Dynamic Time Warping Spaces
Markus Brill, Till Fluschnik, Vincent Froese +3
Dynamic time warping constitutes a major tool for analyzing time series. In particular, computing a mean series of a given sample of series in dynamic time warping spaces (by minim…
Proportional Rankings
Piotr Skowron, Martin Lackner, Markus Brill +2
In this paper we extend the principle of proportional representation to rankings. We consider the setting where alternatives need to be ranked based on approval preferences. In thi…
Multiwinner Approval Rules as Apportionment Methods
Markus Brill, Jean-François Laslier, Piotr Skowron
We establish a link between multiwinner elections and apportionment problems by showing how approval-based multiwinner election rules can be interpreted as methods of apportionment…
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…
Justified Representation in Approval-Based Committee Voting
Haris Aziz, Markus Brill, Vincent Conitzer +3
We consider approval-based committee voting, i.e. the setting where each voter approves a subset of candidates, and these votes are then used to select a fixed-size set of winners…
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…
Testing Substitutability of Weak Preferences
Haris Aziz, Markus Brill, Paul Harrenstein
In many-to-many matching models, substitutable preferences constitute the largest domain for which a pairwise stable matching is guaranteed to exist. In this note, we extend the re…