New Frontiers for Parameterized Complexity (Research Project)

Funding Organisation: The Austrian Science Fund, FWF
Duration: 1 September 2018 – 31 August 2022
Project Number: FWF P 31336

Project Team

Research Statement

Many important computational problems are intractable on general instances. However, realistic problem instances often contain a certain hidden structure that can be exploited to solve the problem efficiently. The parameterized complexity paradigm provides the perfect tools and techniques to formalize, quantify and exploit various forms of structure in order to efficiently solve a plethora of NP-hard problems. This paradigm has been applied in many fundamental areas of computer science with great success, including graph algorithms, computational logic, boolean satisfiability, constraint satisfaction and others. However, there are prominent areas of computer science where we still lack a thorough understanding of the parameterized complexity of key computational problems.

This project aims at investigating the parameterized complexity of fundamental problems in two such high-impact areas: integer linear programming and machine learning. The obtained results will allow the design of efficient algorithms capable of exploiting various natural forms of structure in order to find exact solutions for NP-hard problems in these important areas of computer science. A secondary aim of the project is to apply newly obtained insights and advancements in other, including more traditional, frontiers of parameterized complexity research.

 

Publications

2022

16 results

2022
[16]	An efficient algorithm for counting Markov equivalent DAGs Robert Ganian, Thekla Hamm, Topi Talvitie Artificial Intelligence, volume 304, pages 103648, 2022. [bibtex] [pdf] [doi]
[15]	Threshold Treewidth and Hypertree Width Robert Ganian, Andre Schidler, Manuel Sorge, Stefan Szeider Journal of Artificial Intelligence Research, volume 74, pages 1687–1713, 2022. [bibtex] [pdf] [doi]
[14]	Algorithmic Applications of Tree-Cut Width Robert Ganian, Eun Jung Kim, Stefan Szeider SIAM J. Discrete Math., volume 36, number 4, pages 2635–2666, 2022. [bibtex] [pdf] [doi]
[13]	Sum-of-Products with Default Values: Algorithms and Complexity Results Robert Ganian, Eun Jung Kim, Friedrich Slivovsky, Stefan Szeider Journal of Artificial Intelligence Research, volume 33, pages 535–552, 2022. [bibtex] [pdf]
[12]	On Covering Segments with Unit Intervals Dan Bergren, Eduard Eiben, Robert Ganian, Iyad Kanj SIAM J. Discret. Math., volume 36, number 2, pages 1200–1230, 2022. [bibtex] [pdf] [doi]
[11]	The Complexity of Temporal Vertex Cover in Small-Degree Graphs Thekla Hamm, Nina Klobas, George B. Mertzios, Paul G. Spirakis Thirty-Sixth AAAI Conference on Artificial Intelligence, AAAI 2022, pages 10193–10201, 2022, AAAI Press. [bibtex] [pdf]
[10]	Parameterised Partially-Predrawn Crossing Number Thekla Hamm, Petr Hlinený 38th International Symposium on Computational Geometry, SoCG 2022, June 7-10, 2022, Berlin, Germany (Xavier Goaoc, Michael Kerber, eds.), volume 224 of LIPIcs, pages 46:1–46:15, 2022, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf] [doi]
[9]	Hedonic Diversity Games: A Complexity Picture with More than Two Colors Robert Ganian, Thekla Hamm, Dusan Knop, Simon Schierreich, Ondrej Suchý Thirty-Sixth AAAI Conference on Artificial Intelligence, AAAI 2022, pages 5034–5042, 2022, AAAI Press. [bibtex] [pdf]
[8]	The Complexity of k-Means Clustering when Little is Known Robert Ganian, Thekla Hamm, Viktoriia Korchemna, Karolina Okrasa, Kirill Simonov International Conference on Machine Learning, ICML 2022, 17-23 July 2022, Baltimore, Maryland, USA (Kamalika Chaudhuri, Stefanie Jegelka, Le Song, Csaba Szepesvári, Gang Niu, Sivan Sabato, eds.), volume 162 of Proceedings of Machine Learning Research, pages 6960–6987, 2022, PMLR. [bibtex] [pdf]
[7]	The Fine-Grained Complexity of Graph Homomorphism Parameterized by Clique-Width Robert Ganian, Thekla Hamm, Viktoriia Korchemna, Karolina Okrasa, Kirill Simonov 49th International Colloquium on Automata, Languages, and Programming, ICALP 2022, July 4-8, 2022, Paris, France (Mikolaj Bojanczyk, Emanuela Merelli, David P. Woodruff, eds.), volume 229 of LIPIcs, pages 66:1–66:20, 2022, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf] [doi]
[6]	Weighted Model Counting with Twin-Width Robert Ganian, Filip Pokrývka, Andre Schidler, Kirill Simonov, Stefan Szeider 25th International Conference on Theory and Applications of Satisfiability Testing, SAT 2022, August 2-5, 2022, Haifa, Israel (Kuldeep S. Meel, Ofer Strichman, eds.), volume 236 of LIPIcs, pages 15:1–15:17, 2022, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf] [doi]
[5]	A Unifying Framework for Characterizing and Computing Width Measures Eduard Eiben, Robert Ganian, Thekla Hamm, Lars Jaffke, O-joung Kwon 13th Innovations in Theoretical Computer Science Conference, ITCS 2022, 2022, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf]
[4]	The Complexity of Envy-Free Graph Cutting Argyrios Deligkas, Eduard Eiben, Robert Ganian, Thekla Hamm, Sebastian Ordyniak Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence, IJCAI 2022, Vienna, Austria, 23-29 July 2022 (Luc De Raedt, ed.), pages 237–243, 2022, ijcai.org. [bibtex] [pdf] [doi]
[3]	Parameterized Algorithms for Upward Planarity Steven Chaplick, Emilio Di Giacomo, Fabrizio Frati, Robert Ganian, Chrysanthi N. Raftopoulou, Kirill Simonov 38th International Symposium on Computational Geometry, SoCG 2022, June 7-10, 2022, Berlin, Germany (Xavier Goaoc, Michael Kerber, eds.), volume 224 of LIPIcs, pages 26:1–26:16, 2022, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf] [doi]
[2]	Lossy Kernelization of Same-Size Clustering Sayan Bandyapadhyay, Fedor V. Fomin, Petr A. Golovach, Nidhi Purohit, Kirill Siminov Computer Science – Theory and Applications: 17th International Computer Science Symposium in Russia, CSR 2022, Virtual Event, June 29 – July 1, 2022, Proceedings, pages 96–114, 2022, Springer-Verlag. [bibtex] [pdf] [doi]
[1]	How to Find a Good Explanation for Clustering? Sayan Bandyapadhyay, Fedor V. Fomin, Petr A. Golovach, William Lochet, Nidhi Purohit, Kirill Simonov Thirty-Sixth AAAI Conference on Artificial Intelligence, AAAI 2022, pages 3904–3912, 2022, AAAI Press. [bibtex] [pdf]

2021

17 results

2021
[17]	Measuring what matters: A hybrid approach to dynamic programming with treewidth Eduard Eiben, Robert Ganian, Thekla Hamm, O-joung Kwon J. Comput. Syst. Sci., volume 121, pages 57–75, 2021. [bibtex] [pdf]
[16]	New Width Parameters for SAT and Sharp-SAT Robert Ganian, Stefan Szeider Artificial Intelligence, volume 295, pages 103460, 2021. [bibtex] [pdf] [doi]
[15]	On Structural Parameterizations of the Edge Disjoint Paths Problem Robert Ganian, Sebastian Ordyniak, M. S. Ramanujan Algorithmica, volume 83, number 6, pages 1605–1637, 2021. [bibtex] [pdf]
[14]	The Power of Cut-Based Parameters for Computing Edge-Disjoint Paths Robert Ganian, Sebastian Ordyniak Algorithmica, volume 83, number 2, pages 726–752, 2021. [bibtex] [pdf]
[13]	On Structural Parameterizations of the Bounded-Degree Vertex Deletion Problem Robert Ganian, Fabian Klute, Sebastian Ordyniak Algorithmica, volume 83, number 1, pages 297–336, 2021. [bibtex] [pdf]
[12]	On Strict (Outer-)Confluent Graphs Henry Förster, Robert Ganian, Fabian Klute, Martin Nöllenburg J. Graph Algorithms Appl., 2021. [bibtex] [pdf]
[11]	Graphs with at most two moplexes Clément Dallard, Robert Ganian, Meike Hatzel, Matjaz Krnc, Martin Milanic Journal of Graph Theory, 2021, Wiley Online Library. [bibtex]
[10]	The complexity landscape of decompositional parameters for ILP: Programs with Few Global Variables and Constraints Pavel Dvořák, Eduard Eiben, Robert Ganian, Dušan Knop, Sebastian Ordyniak Artificial Intelligence, 2021. [bibtex] [pdf]
[9]	Towards a Polynomial Kernel for Directed Feedback Vertex Set Benjamin Bergougnoux, Eduard Eiben, Robert Ganian, Sebastian Ordyniak, M. S. Ramanujan Algorithmica, volume 83, number 5, pages 1201–1221, 2021. [bibtex] [pdf]
[8]	Computing Kemeny Rankings from d-Euclidean Preferences Thekla Hamm, Martin Lackner, Anna Rapberger Algorithmic Decision Theory - 7th International Conference, ADT 2021, Toulouse, France, November 3-5, 2021, Proceedings, volume 13023 of Lecture Notes in Computer Science, pages 147–161, 2021, Springer Verlag. [bibtex]
[7]	The Complexity of Bayesian Network Learning: Revisiting the Superstructure Robert Ganian, Viktoriia Korchemna Advances in Neural Information Processing Systems 34: Annual Conference on Neural Information Processing Systems 2021, NeurIPS 2021, December 6-14, 2021, virtual (Marc'Aurelio Ranzato, Alina Beygelzimer, Yann N. Dauphin, Percy Liang, Jennifer Wortman Vaughan, eds.), pages 430–442, 2021. [bibtex] [pdf]
[6]	The Complexity of Object Association in Multiple Object Tracking Robert Ganian, Thekla Hamm, Sebastian Ordyniak Thirty-Fifth AAAI Conference on Artificial Intelligence, AAAI 2021, Virtual Event, February 2-9, 2021, pages 1388–1396, 2021, AAAI Press. [bibtex] [pdf]
[5]	Crossing-Optimal Extension of Simple Drawings Robert Ganian, Thekla Hamm, Fabian Klute, Irene Parada, Birgit Vogtenhuber 48th International Colloquium on Automata, Languages, and Programming, ICALP 2021, July 12-16, 2021, Glasgow, Scotland (Virtual Conference) (Nikhil Bansal, Emanuela Merelli, James Worrell, eds.), volume 198 of LIPIcs, pages 72:1–72:17, 2021, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf]
[4]	The Parameterized Complexity of Clustering Incomplete Data Eduard Eiben, Robert Ganian, Iyad Kanj, Sebastian Ordyniak, Stefan Szeider Proceeding of AAAI-21, the Thirty-Fifth AAAI Conference on Artificial Intelligence, pages 7296–7304, 2021, AAAI Press. [bibtex] [pdf]
[3]	The Parameterized Complexity of Connected Fair Division Argyrios Deligkas, Eduard Eiben, Robert Ganian, Thekla Hamm, Sebastian Ordyniak Proceedings of the Thirtieth International Joint Conference on Artificial Intelligence, IJCAI 2021, Virtual Event / Montreal, Canada, 19-27 August 2021 (Zhi-Hua Zhou, ed.), pages 139–145, 2021, ijcai.org. [bibtex] [pdf]
[2]	Graphs with two moplexes Clément Dallard, Robert Ganian, Meike Hatzel, Matjaz Krnc, Martin Milanic Proceedings of the XI Latin and American Algorithms, Graphs and Optimization Symposium, LAGOS 2021, 2021, Elsevier. [bibtex] [pdf]
[1]	Worbel: Aggregating Point Labels into Word Clouds Sujoy Bhore, Robert Ganian, Guangping Li, Martin Nollenburg, Jules Wulms Proceedings of the International Conference on Advances in Geographic Information Systems 2021 (ACM SIGSPATIAL 2021), 2021. [bibtex] [pdf]

2020

14 results

2020
[14]	Parameterized Algorithms for Book Embedding Problems Sujoy Bhore, Robert Ganian, Fabrizio Montecchiani, Martin Nöllenburg J. Graph Algorithms Appl., 2020. [bibtex] [doi]
[13]	Using decomposition-parameters for QBF: Mind the prefix! Eduard Eiben, Robert Ganian, Sebastian Ordyniak J. Comput. Syst. Sci., volume 110, pages 1–21, 2020. [bibtex] [pdf]
[12]	On Existential MSO and Its Relation to ETH Robert Ganian, Ronald de Haan, Iyad Kanj, Stefan Szeider ACM Trans. Comput. Theory, volume 12, number 4, pages 22:1–22:32, 2020. [bibtex] [pdf] [doi]
[11]	Threshold Treewidth and Hypertree Width Robert Ganian, Andre Schidler, Manuel Sorge, Stefan Szeider Proceeding of IJCAI-PRICAI2020, the 29th International Joint Conference on Artificial Intelligence and the 17th Pacific Rim International Conference on Artificial Intelligence, pages 1898–1904, 2020. [bibtex] [pdf] [doi]
[10]	Fixed-Parameter Tractability of Dependency QBF with Structural Parameters Robert Ganian, Tomáš Peitl, Friedrich Slivovsky, Stefan Szeider Proceedings of the 17th International Conference on Principles of Knowledge Representation and Reasoning, KR 2020 (Diego Calvanese, Esra Erdem, Michael Thielscher, eds.), pages 392–402, 2020. [bibtex] [pdf]
[9]	On the Parameterized Complexity of Clustering Incomplete Data into Subspaces of Small Rank Robert Ganian, Iyad Kanj, Sebastian Ordyniak, Stefan Szeider Proceeding of AAAI-20, the Thirty-Fourth AAAI Conference on Artificial Intelligence, February 7–12, 2020, New York, pages 3906–3913, 2020, AAAI Press. [bibtex] [pdf]
[8]	An Efficient Algorithm for Counting Markov Equivalent DAGs Robert Ganian, Thekla Hamm, Topi Talvitie The Thirty-Fourth AAAI Conference on Artificial Intelligence, AAAI 2020, New York, NY, USA, February 7-12, 2020, pages 10136–10143, 2020, AAAI Press. [bibtex] [pdf]
[7]	The Complexity Landscape of Resource-Constrained Scheduling Robert Ganian, Thekla Hamm, Guillaume Mescoff Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence, IJCAI 2020 (Christian Bessiere, ed.), pages 1741–1747, 2020, ijcai.org. [bibtex] [pdf]
[6]	Parameterized Complexity of Envy-Free Resource Allocation in Social Networks Eduard Eiben, Robert Ganian, Thekla Hamm, Sebastian Ordyniak The Thirty-Fourth AAAI Conference on Artificial Intelligence, AAAI 2020, New York, NY, USA, February 7-12, 2020, pages 7135–7142, 2020, AAAI Press. [bibtex] [pdf]
[5]	Extending Nearly Complete 1-Planar Drawings in Polynomial Time Eduard Eiben, Robert Ganian, Thekla Hamm, Fabian Klute, Martin Nöllenburg 45th International Symposium on Mathematical Foundations of Computer Science, MFCS 2020, August 24-28, 2020, Prague, Czech Republic (Javier Esparza, Daniel Král', eds.), volume 170 of LIPIcs, pages 31:1–31:16, 2020, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf]
[4]	Extending Partial 1-Planar Drawings Eduard Eiben, Robert Ganian, Thekla Hamm, Fabian Klute, Martin Nöllenburg 47th International Colloquium on Automata, Languages, and Programming, ICALP 2020, July 8-11, 2020, Saarbrücken, Germany (Virtual Conference) (Artur Czumaj, Anuj Dawar, Emanuela Merelli, eds.), volume 168 of LIPIcs, pages 43:1–43:19, 2020, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf]
[3]	Stable Matchings with Diversity Constraints: Affirmative Action is beyond NP Jiehua Chen, Robert Ganian, Thekla Hamm Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence, IJCAI 2020 (Christian Bessiere, ed.), pages 146–152, 2020, ijcai.org. [bibtex] [pdf]
[2]	Parameterized Algorithms for Queue Layouts Sujoy Bhore, Robert Ganian, Fabrizio Montecchiani, Martin Nöllenburg Graph Drawing and Network Visualization - 28th International Symposium, GD 2020, Vancouver, BC, Canada, September 16-18, 2020, Revised Selected Papers (David Auber, Pavel Valtr, eds.), volume 12590 of Lecture Notes in Computer Science, pages 40–54, 2020, Springer Verlag. [bibtex] [pdf]
[1]	On Covering Segments with Unit Intervals Dan Bergren, Eduard Eiben, Robert Ganian, Iyad Kanj 37th International Symposium on Theoretical Aspects of Computer Science, STACS 2020, March 10-13, 2020, Montpellier, France (Christophe Paul, Markus Bläser, eds.), volume 154 of LIPIcs, pages 13:1–13:17, 2020, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf]

2019

16 results

2019
[16]	Solving Integer Linear Programs by Exploiting Variable-Constraint Interactions: A Survey Robert Ganian, Sebastian Ordyniak Algorithms, volume 12, number 12, pages 248, 2019. [bibtex] [pdf]
[15]	On the Complexity Landscape of Connected f-Factor Problems Robert Ganian, N. S. Narayanaswamy, Sebastian Ordyniak, C. S. Rahul, M. S. Ramanujan Algorithmica, volume 81, number 6, pages 2606–2632, 2019. [bibtex] [pdf]
[14]	Parameterized Complexity of Asynchronous Border Minimization Robert Ganian, Martin Kronegger, Andreas Pfandler, Alexandru Popa Algorithmica, volume 81, number 1, pages 201–223, 2019. [bibtex] [pdf]
[13]	Shrub-Depth: Capturing Height of Dense Graphs Robert Ganian, Petr Hlinený, Jaroslav Nesetril, Jan Obdrzálek, Patrice Ossona de Mendez Logical Methods in Computer Science, 2019. [bibtex] [pdf]
[12]	Counting linear extensions: Parameterizations by treewidth Eduard Eiben, Robert Ganian, Kustaa Kangas, Sebastian Ordyniak Algorithmica, 2019. [bibtex] [pdf]
[11]	Group Activity Selection with Few Agent Types Robert Ganian, Sebastian Ordyniak, C. S. Rahul 27th Annual European Symposium on Algorithms, ESA 2019, September 9-11, 2019, Munich/Garching, Germany (Michael A. Bender, Ola Svensson, Grzegorz Herman, eds.), pages 48:1–48:16, 2019. [bibtex] [pdf]
[10]	Finding Linear Arrangements of Hypergraphs with Bounded Cutwidth in Linear Time Thekla Hamm 14th International Symposium on Parameterized and Exact Computation, IPEC 2019, September 11-13, 2019, Munich, Germany (Bart M. P. Jansen, Jan Arne Telle, eds.), volume 148 of LIPIcs, pages 20:1–20:14, 2019, Schloss Dagstuhl - Leibniz-Zentrum für Informatik. [bibtex] [pdf] [doi]
[9]	A Join-Based Hybrid Parameter for Constraint Satisfaction Robert Ganian, Sebastian Ordyniak, Stefan Szeider Proceedings of CP 2019, the 25th International Conference on Principles and Practice of Constraint Programming (Thomas Schiex, Simon de Givry, eds.), volume 11802 of Lecture Notes in Computer Science, pages 195–212, 2019, Springer Verlag. [bibtex] [pdf] [doi]
[8]	The Power of Cut-Based Parameters for Computing Edge Disjoint Paths Robert Ganian, Sebastian Ordyniak Graph-Theoretic Concepts in Computer Science - 45th International Workshop, WG 2019, Vall de Núria, Spain, June 19-21, 2019, Revised Papers (Ignasi Sau, Dimitrios M. Thilikos, eds.), pages 190–204, 2019. [bibtex] [pdf]
[7]	SAT-Encodings for Treecut Width and Treedepth Robert Ganian, Neha Lodha, Sebastian Ordyniak, Stefan Szeider Proceedings of ALENEX 2019, the 21st Workshop on Algorithm Engineering and Experiments (Stephen G. Kobourov, Henning Meyerhenke, eds.), pages 117–129, 2019, Society for Industrial and Applied Mathematics (SIAM). [bibtex] [pdf] [doi]
[6]	On Strict (Outer-)Confluent Graphs Henry Förster, Robert Ganian, Fabian Klute, Martin Nöllenburg Graph Drawing and Network Visualization - 27th International Symposium, GD 2019, Prague, Czech Republic, September 17-20, 2019, Proceedings (Daniel Archambault, Csaba D. Tóth, eds.), volume 11904 of Lecture Notes in Computer Science, pages 147–161, 2019, Springer Verlag. [bibtex] [pdf]
[5]	Solving integer quadratic programming via explicit and structural restrictions Eduard Eiben, Robert Ganian, Dusan Knop, Sebastian Ordyniak The Thirty-Third AAAI Conference on Artificial Intelligence, AAAI 2019, Honolulu, Hawaii, USA, January 27 - February 1, 2019 (Pascal Van Hentenryck, Zhi-Hua Zhou, eds.), pages 1477–1484, 2019. [bibtex] [pdf]
[4]	The Parameterized Complexity of Cascading Portfolio Scheduling Eduard Eiben, Robert Ganian, Iyad Kanj, Stefan Szeider Proceedings of NeurIPS 2019, the Thirty-third Conference on Neural Information Processing Systems (Hanna M. Wallach, Hugo Larochelle, Alina Beygelzimer, Florence d'Alché-Buc, Emily B. Fox, Roman Garnett, eds.), pages 7666–7676, 2019. [bibtex] [pdf]
[3]	Measuring what Matters: A Hybrid Approach to Dynamic Programming with Treewidth Eduard Eiben, Robert Ganian, Thekla Hamm, O-joung Kwon 44th International Symposium on Mathematical Foundations of Computer Science, MFCS 2019, August 26-30, 2019, Aachen, Germany (Peter Rossmanith, Pinar Heggernes, Joost-Pieter Katoen, eds.), pages 42:1–42:15, 2019. [bibtex] [pdf]
[2]	Integer Programming and Incidence Treedepth Eduard Eiben, Robert Ganian, Dusan Knop, Sebastian Ordyniak, Michal Pilipczuk, Marcin Wrochna Integer Programming and Combinatorial Optimization - 20th International Conference, IPCO 2019, Ann Arbor, MI, USA, May 22-24, 2019, Proceedings (Andrea Lodi, Viswanath Nagarajan, eds.), volume 11480 of Lecture Notes in Computer Science, pages 194–204, 2019, Springer Verlag. [bibtex] [pdf]
[1]	Parameterized Algorithms for Book Embedding Problems Sujoy Bhore, Robert Ganian, Fabrizio Montecchiani, Martin Nöllenburg Graph Drawing and Network Visualization - 27th International Symposium, GD 2019, Prague, Czech Republic, September 17-20, 2019, Proceedings (Daniel Archambault, Csaba D. Tóth, eds.), volume 11904 of Lecture Notes in Computer Science, pages 365–378, 2019, Springer Verlag. [bibtex] [pdf]