Publications

Conference Papers↑

• EC 2026NewA. Baychkov, M. Brill, and M. Utke. Mixed Voting Rules for Participatory Budgeting. In Proceedings of the 27th ACM Conference on Economics and Computation (EC). Forthcoming, 2026. arXiv
• IJCAI 2026NewM. Brill, R. Colley, A.-M. George, G. Lisowski, G. Papasotiropoulos, and U. Schmidt-Kraepelin. Cycles in Liquid Democracy: A Game-Theoretic Justification. In Proceedings of the 35th International Joint Conference on Artificial Intelligence (IJCAI). Forthcoming, 2026. arXiv
• AAAI 2026Michelle Döring, Markus Brill, Jobst Heitzig. The River Voting Method. In Proceedings of the 40th AAAI Conference on Artificial Intelligence (AAAI), pages 16846–16854. AAAI Press, 2026. link arXiv
• AAAI 2026Anton Baychkov, Markus Brill, Jannik Peters. Utilitarian Guarantees for the Method of Equal Shares. In Proceedings of the 40th AAAI Conference on Artificial Intelligence (AAAI), pages 16656–16663. AAAI Press, 2026. link arXiv
• AAAI 2025T. Bardal, M. Brill, D. McCune, and J. Peters. Proportional Representation in Practice: Quantifying Proportionality in Ordinal Elections. In Proceedings of the 39th AAAI Conference on Artificial Intelligence (AAAI), pages 13581–13588. AAAI Press, 2025. link arXiv
• AAAI 2024N. Boehmer, M. Brill, A. Cevallos, J. Gehrlein, L. Sánchez-Fernández, and U. Schmidt-Kraepelin. Approval-based committee voting in practice: A case study of (over-)representation in the Polkadot blockchain. Proceedings of the 38th AAAI Conference on Artificial Intelligence (AAAI), pages 9519–9527. AAAI Press, 2024. link arXiv
• AAAI 2024M. Brill and J. Peters. Completing Priceable Committees: Utilitarian and Representation Guarantees. Proceedings of the 38th AAAI Conference on Artificial Intelligence (AAAI), pages 9528–9536. AAAI Press, 2024. link arXiv
• AAMAS 2024M. Revel, N. Boehmer, R. Colley, M. Brill, P. Faliszewski, and E. Elkind. Selecting Representative Bodies: An Axiomatic View. In Proceedings of the 23rd International Conference on Autonomous Agents and Multiagent Systems (AAMAS) Blue Sky Ideas Track, 2024. arXiv
• AAAI 2024A. Imber and J. Israel and M. Brill and H. Shachnai and B. Kimelfeld. Spatial Voting with Incomplete Voter Information. Proceedings of the 38th AAAI Conference on Artificial Intelligence (AAAI), pages 9790– 9797. AAAI Press, 2024. link arXiv
• AAAI 2023M. Brill, H. Dindar, J. Israel, J. Lang, J. Peters, and U. Schmidt-Kraepelin. Multiwinner Voting with Possibly Unavailable Candidates. In Y. Chen and J. Neville, editors, Proceedings of the 37th AAAI Conference on Artificial Intelligence (AAAI), pages 5532-5539. AAAI Press, 2023. link pdf full version
• IJCAI 2023M. Brill, E. Markakis, G. Papasotiropoulos, and J. Peters. Proportionality Guarantees in Elections with Interdependent Issues. Proceedings of the 32nd International Joint Conference on Artificial Intelligence (IJCAI), pages 2537-2545. IJCAI, 2023. pdf
• AAAI 2023M. Brill, S. Forster, M. Lackner, J. Maly, and J. Peters. Proportionality in Approval-Based Participatory Budgeting. In Y. Chen and J. Neville, editors, Proceedings of the 37th AAAI Conference on Artificial Intelligence (AAAI), pages 5524-5531. AAAI Press, 2023. link pdf arXiv
• EC 2023M. Brill and J. Peters. Robust and Verifiable Proportionality Axioms for Multiwinner Voting. Proceedings of the 24th ACM Conference on Economics and Computation (EC), page 301. ACM, 2023. link arXiv
• AAAI 2022A. Imber, J. Israel, M. Brill, and B. Kimelfeld. Approval-Based Committee Voting under Incomplete Information. In V. Honavar and M. Spaan, editors, Proceedings of the 36th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2022. pdf arXiv
• AAAI 2022M. Brill, J. Israel, E. Micha, and J. Peters. Individual Representation in Approval-Based Committee Voting. In V. Honavar and M. Spaan, editors, Proceedings of the 36th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2022. pdf arXiv
• AAAI 2022M. Brill, T. Delemazure, A.-M. George, M. Lackner, and U. Schmidt-Kraepelin. Liquid Democracy with Ranked Delegations. In V. Honavar and M. Spaan, editors, Proceedings of the 36th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2022. pdf arXiv
• AAMAS 2022N. Boehmer, M. Brill, and U. Schmidt-Kraepelin. Proportional Representation in Matching Markets: Selecting Multiple Matchings under Dichotomous Preferences. In P. Faliszewski and V. Mascardi, editors, Proceedings of the 21st International Conference on Autonomous Agents and Multiagent Systems (AAMAS). IFAAMAS, 2022. pdf arXiv
• IJCAI 2021J. Israel and M. Brill. Dynamic Proportional Rankings. In Z.-H. Zhou, editor, Proceedings of the 30th International Joint Conference on Artificial Intelligence (IJCAI), pages 261–267. IJCAI, 2021. link pdf arXiv
• AAAI 2021M. Brill, U. Schmidt-Kraepelin, and W. Suksompong. Margin of victory in tournaments: Structural and experimental results. In K. Leyton-Brown and Mausam, editors, Proceedings of the 35th AAAI Conference on Artificial Intelligence (AAAI), pages 5228–5235. AAAI Press, 2021. link pdf
• AAAI 2021L. Sánchez-Fernández, N. Fernández García, J. A. Fisteus, and M. Brill. The Maximin Support Method: An Extension of the D’Hondt Method to Approval-Based Multiwinner Elections. In K. Leyton-Brown and Mausam, editors, Proceedings of the 35th AAAI Conference on Artificial Intelligence (AAAI), pages 5690–5697. AAAI Press, 2021. link pdf
• AAAI 2020M. Brill, P. Gölz, D. Peters, U. Schmidt-Kraepelin, and K. Wilker. Approval-based apportionment. In V. Conitzer and F. Sha, editors, Proceedings of the 34th AAAI Conference on Artificial Intelligence (AAAI), pages 1854–1861. AAAI Press, 2020. link pdf
• AAAI 2020M. Brill, U. Schmidt-Kraepelin, and W. Suksompong. Refining tournament solutions via margin of victory. In V. Conitzer and F. Sha, editors, Proceedings of the 34th AAAI Conference on Artificial Intelligence (AAAI), pages 1862–1869. AAAI Press, 2020. link pdf
• AAMAS 2019M. Brill, P. Faliszewski, F. Sommer, and N. Talmon. Approximation Algorithms for BalancedCC Multiwinner Rules. In N. Agmon and M. E. Taylor, editors, Proceedings of the 18th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS), pages 494–502. IFAAMAS, 2019. Shortlisted for the AAMAS 2019 Best Paper Award. link pdf
• SDM 2018M. Brill, T. Fluschnik, V. Froese, B. J. Jain, R. Niedermeier, D. Schultz. Exact Mean Computation in Dynamic Time Warping Spaces. In Proceedings of the 18th SIAM International Conference on Data Mining (SDM), 2018. link pdf arXiv
• AAMAS 2018M. Brill. Interactive Democracy. In M. Dastani and G. Sukthankar, editors, Proceedings of the 17th International Conference on Autonomous Agents and Multiagent Systems (AAMAS) Blue Sky Ideas Track, pages 1183–1187. IFAAMAS, 2018. link pdf
• IJCAI 2018M. Brill and N. Talmon. Pairwise Liquid Democracy. In J. Lang, editor, Proceedings of the 27th International Joint Conference on Artificial Intelligence (IJCAI), pages 137–143. IJCAI, 2018. link pdf
• AAAI 2017M. Brill, J.-F. Laslier, and P. Skowron. Multiwinner Approval Rules as Apportionment Methods. In S. Singh and S. Markovitch, editors, Proceedings of the 31st AAAI Conference on Artificial Intelligence (AAAI), AAAI Press, 2017. link pdf arXiv
• AAAI 2017M. Brill, R. Freeman, S. Janson, and M. Lackner. Phragmén’s Voting Methods and Justified Representation. In S. Singh and S. Markovitch, editors, Proceedings of the 31st AAAI Conference on Artificial Intelligence (AAAI), AAAI Press, 2017. link pdf
• IJCAI 2017P. Skowron, M. Lackner, M. Brill, D. Peters, E. Elkind. Proportional Rankings. In C. Sierra, editor, Proceedings of the 26th International Joint Conference on Artificial Intelligence (IJCAI), 2017. link pdf arXiv
• AAAI 2016M. Brill, R. Freeman, and V. Conitzer. Computing Possible and Necessary Equilibrium Actions (and Bipartisan Set Winners). In Proceedings of the 30th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2016. pdf arXiv
• AAMAS 2016M. Brill, V. Conitzer, R. Freeman, and N. Shah. False-Name-Proof Recommendations in Social Networks. In Proceedings of the 15th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS). IFAAMAS, 2016. pdf
• IJCAI 2016M. Brill, E. Elkind, U. Endriss, and U. Grandi. Pairwise Diffusion of Preference Rankings in Social Networks. In S. Kambhampati, editor, Proceedings of the 25th International Joint Conference on Artificial Intelligence (IJCAI), 2016. link pdf
• AAAI 2016V. Conitzer, R. Freeman, M. Brill, and Y. Li. Rules for Choosing Societal Tradeoffs. In Proceedings of the 30th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2016. pdf
• AAMAS 2015V. Conitzer, M. Brill, and R. Freeman. Crowdsourcing Societal Tradeoffs. In Proceedings of the 14th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS) Blue Sky Ideas track. IFAAMAS, 2015. pdf
• AAMAS 2015R. Freeman, M. Brill, and V. Conitzer. General Tiebreaking Schemes for Computational Social Choice. In Proceedings of the 14th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS). IFAAMAS, 2015. pdf
• AAAI 2015H. Aziz, M. Brill, V. Conitzer, E. Elkind, R. Freeman, and T. Walsh. Justified Representation in Approval-Based Committee Voting. In B. Bonet, S. Koenig, editors, Proceedings of the 29th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2015. link pdf
• AAAI 2015M. Brill and V. Conitzer. Strategic Voting and Strategic Candidacy. In B. Bonet, S. Koenig, editors, Proceedings of the 29th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2015. link pdf
• AAAI 2014F. Brandt, M. Brill, and P. Harrenstein. Extending tournament solutions. In C. E. Brodley and P. Stone, editors, Proceedings of the 28th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2014. link pdf
• AAAI 2014R. Freeman, M. Brill, and V. Conitzer. On the Axiomatic Characterization of Runoff Voting Rules. In C. E. Brodley and P. Stone, editors, Proceedings of the 28th AAAI Conference on Artificial Intelligence (AAAI). AAAI Press, 2014. pdf
• AAMAS 2013H. Aziz, F. Brandt, and M. Brill. On the tradeoff between economic efficiency and strategyproofness in randomized social choice. In Proceedings of the 12th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS), pages 455-462. IFAAMAS, 2013. pdf
• WINE 2013H. Aziz, F. Brandt, and M. Brill. The computational complexity of random serial dictatorship. In Y. Chen and N. Immorlica, editors, Proceedings of the 9th Conference on Web and Internet Economics (WINE), Lecture Notes in Computer Science (LNCS). Springer-Verlag, 2013. pdf
• EC 2012F. Brandt and M. Brill. Computing dominance-based solution concepts. In B. Faltings, K. Leyton-Brown, and P. Ipeirotis, editors, Proceedings of the 13th ACM Conference on Electronic Commerce (ACM-EC), page 233. ACM Press, 2012. link pdf
• AAMAS 2012H. Aziz, M. Brill, F. Fischer, P. Harrenstein, J. Lang, and H. G. Seedig. Possible and necessary winners of partial tournaments. In V. Conitzer and M. Winikoff, editors, Proceedings of the 11th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS). IFAAMAS, 2012. link pdf
• AAAI 2012M. Brill and F. Fischer. The price of neutrality for the ranked pairs method. In J. Hoffmann and B. Selman, editors, Proceedings of the 26th AAAI Conference on Artificial Intelligence (AAAI), pages 1299-1305. AAAI Press, 2012. pdf
• TARK 2011F. Brandt and M. Brill. Necessary and sufficient conditions for the strategyproofness of irresolute social choice functions. In K. Apt, editor, Proceedings of the 13th Conference on Theoretical Aspects of Rationality and Knowledge (TARK), pages 136-142. ACM Press, 2011. link pdf
• IJCAI 2011F. Brandt, M. Brill, and H. G. Seedig. On the fixed-parameter tractability of composition-consistent tournament solutions. In T. Walsh, editor, Proceedings of the 22nd International Joint Conference on Artificial Intelligence (IJCAI), pages 85-90. AAAI Press, 2011. link pdf
• AAAI 2010F. Brandt, M. Brill, E. Hemaspaandra, and L. Hemaspaandra. Bypassing combinatorial protections: Polynomial-time algorithms for single-peaked electorates. In M. Fox and D. Poole, editors, Proceedings of the 24th AAAI Conference on Artificial Intelligence (AAAI), pages 715-722. AAAI Press, 2010. link pdf
• AAMAS 2010F. Brandt, M. Brill, F. Fischer, and P. Harrenstein. Minimal retentive sets in tournaments. In W. vander Hoek, G. A. Kaminka, Y. Lespérance, and M. Luck, editors, Proceedings of the 9th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS), pages 47-54. IFAAMAS, 2010. link pdf
• AAMAS 2009F. Brandt, M. Brill, F. Fischer, and P. Harrenstein. Computational aspects of Shapley’s saddles. In K. S. Decker, J. S. Sichman, C. Sierra, and C. Castelfranchi, editors, Proceedings of the 8th International Joint Conference on Autonomous Agents and Multi-Agent Systems (AAMAS), pages 209-216. IFAAMAS, 2009. link pdf
• SAGT 2009F. Brandt, M. Brill, F. Fischer, and P. Harrenstein. On the complexity of iterated weak dominance in constant-sum games. In M. Mavronicolas and V. G. Papadopoulou, editors, Proceedings of the 2nd International Symposium on Algorithmic Game Theory (SAGT), volume 5814 of Lecture Notes in Computer Science (LNCS), pages 287-298. Springer-Verlag, 2009. link pdf
• SAGT 2009F. Brandt, M. Brill, F. Fischer, and J. Hoffmann. The computational complexity of weak saddles. In M. Mavronicolas and V. G. Papadopoulou, editors, Proceedings of the 2nd International Symposium on Algorithmic Game Theory (SAGT), volume 5814 of Lecture Notes in Computer Science (LNCS), pages 238-249. Springer-Verlag, 2009. link pdf

Journal Papers↑

• A. Imber, J. Israel, M. Brill, and B. Kimelfeld. Approval-Based Committee Voting under Incomplete Information. Artificial Intelligence, Volume 347, 104381, 2025. link arXiv
• J. Israel and M. Brill. Dynamic Proportional Rankings. Social Choice and Welfare, 64(1–2):221–261, 2025. link pdf
• M. Brill, J. Israel, E. Micha, and J. Peters. Individual Representation in Approval-Based Committee Voting. Social Choice and Welfare, 64(1–2):69–96, 2025. link pdf
• N. Boehmer, M. Brill, and U. Schmidt-Kraepelin. Proportional Representation in Matching Markets: Selecting Multiple Matchings under Dichotomous Preferences. Social Choice and Welfare, 64(1–2):179–220, 2025. link pdf
• M. Brill, P. Gölz, D. Peters, U. Schmidt-Kraepelin, and K. Wilker. Approval-based apportionment. Mathematical Programming, 203(1-2):77-105, 2024. link pdf
• Markus Brill, Rupert Freeman, Svante Janson and Martin Lackner. Phragmén’s voting methods and justified representation. Mathematical Programming, 203(1–2):47–76, 2024. link pdf
• L. Sánchez-Fernández, N. Fernández García, J. A. Fisteus, and M. Brill. The Maximin Support Method: An Extension of the D’Hondt Method to Approval-Based Multiwinner Elections. Mathematical Programming, 203(1–2):107–134, 2024. link pdf
• M. Brill, U. Schmidt-Kraepelin, and W. Suksompong. Margin of Victory for Tournament Solutions. Artificial Intelligence, Volume 302, 2022. link pdf
• S. J. Brams, M. Brill, A.-M. George. The Excess Method: A Multiwinner Approval Voting Procedure to Allocate Wasted Votes. Social Choice and Welfare, 58:283–300, 2022. link pdf
• A. Pommerening, M. Brill, U. Schmidt-Kraepelin, and J. Haufe. Democratising forest management: Applying multiwinner approval voting to tree selection. Forest Ecology and Management, 478:118509, 2020. link pdf
• M. Brill, T. Fluschnik, V. Froese, B. J. Jain, R. Niedermeier, and D. Schultz. Exact Mean Computation in Dynamic Time Warping Spaces. Data Mining and Knowledge Discovery, 33(1):252–291, 2019. link arXiv
• F. Brandt, M. Brill, and P. Harrenstein. Extending tournament solutions. Social Choice and Welfare, 51:193–222, 2018. link pdf
• M. Brill, J.-F. Laslier, and P. Skowron. Multiwinner Approval Rules as Apportionment Methods. Journal of Theoretical Politics, 30(3):358–382, 2018. link arXiv
• F. Brandt, M. Brill, H. G. Seedig, and W. Suksompong. On the structure of stable tournament solutions. Economic Theory, 65(2):483-507, 2018. link pdf
• H. Aziz, F. Brandl, F. Brandt, and M. Brill. On the tradeoff between efficiency and strategyproofness. Games and Economic Behavior, 110:1–18, 2018. link pdf
• H. Aziz, M. Brill, V. Conitzer, E. Elkind, R. Freeman, and T. Walsh. Justified Representation in Approval-Based Committee Voting. Social Choice and Welfare, 48(2):461- 485, 2017. link pdf
• F. Brandt, M. Brill, and W. Suksompong. An Ordinal Minimax Theorem. Games and Economic Behavior, 95:107-112, 2016. link pdf
• F. Brandt and M. Brill. Computing dominance-based solution concepts. ACM Transactions on Economics and Computation (TEAC), Volume 5, Issue 2, Article 9, 2016. link pdf
• F. Brandt, M. Brill, E. Hemaspaandra, and L. Hemaspaandra. Bypassing combinatorial protections: Polynomial-time algorithms for single-peaked electorates. Journal of Artificial Intelligence Research, 53:439-496, 2015. link pdf
• H. Aziz, M. Brill, F. Fischer, P. Harrenstein, J. Lang, and H. G. Seedig. Possible and necessary winners of partial tournaments. Journal of Artificial Intelligence Research, 54:493-534, 2015. link pdf
• H. Aziz, F. Brandt, M. Brill, and J. Mestre. Computational aspects of random serial dictatorship. ACM SIGecom Exchanges, 13(2):26-30, 2014. link pdf
• F. Brandt, M. Brill, F. Fischer, and P. Harrenstein. Minimal retentive sets in tournaments. Social Choice and Welfare, 42(3):551–574, 2014. link pdf
• H. Aziz, M. Brill, and P. Harrenstein. Testing substitutability of weak preferences. Mathematical Social Sciences, 66(1):91-94, 2013. link
• H. Aziz, F. Brandt, and M. Brill. The computational complexity of random serial dictatorship. Economics Letters, 121(3):341–345, 2013. link pdf
• F. Brandt, M. Brill, F. Fischer, and P. Harrenstein. On the complexity of iterated weak dominance in constant-sum games. Theory of Computing Systems, 49(1):162-181, 2011. link pdf
• F. Brandt, M. Brill, F. Fischer, and J. Hoffmann. The computational complexity of weak saddles. Theory of Computing Systems, 49(1):139-161, 2011. link pdf
• F. Brandt, M. Brill, F. Fischer, P. Harrenstein, and J. Hoffmann. Computing Shapley’s saddles. ACM SIGecom Exchanges, 8(2), 2009. link pdf

Book Chapters and Invited Contributions↑

• M. Brill and V. Conitzer. Strategic voting and strategic candidacy. In S. Kurz, N. Maaser, and A. Mayer, editors, Advances in Collective Decision Making: Interdisciplinary Perspectives for the 21st Century, Studies in Choice and Welfare, pages 69–84. Springer, 2023. link
• M. Brill. From Computational Social Choice to Digital Democracy. In Z.-H. Zhou, editor, Proceedings of the 30th International Joint Conference on Artificial Intelligence (IJCAI) Early Career Spotlight Track, pages 4937–4939. IJCAI, 2021. link pdf
• M. Brill. Interactive Democracy: New Challenges for Social Choice Theory. In J.-F. Laslier, H. Moulin, R. Sanver, and W. S. Zwicker, editors, Future of Economic Design, pages 59–66. Springer, 2019. link pdf
• F. Brandt, M. Brill, and P. Harrenstein. Tournament Solutions. In F. Brandt, V. Conitzer, U. Endriss, J. Lang, and A. Procaccia, editors, Handbook of Computational Social Choice. Cambridge University Press, 2016. amazon pdf
• M. Brill. Mengenwertige Lösungskonzepte in Spieltheorie und Social-Choice-Theorie. In S. Hölldobler et al., editors, Ausgezeichnete Informatikdissertationen 2012, volume D-13 of GI-Edition Lecture Notes in Informatics (LNI), pages 41–50. Gesellschaft für Informatik e.V. (GI), 2013. link pdf

Thesis↑

• M. Brill. Set-valued solution concepts in social choice and game theory: Axiomatic and computational aspects. PhD thesis, Technische Universität München, 2012. link pdf