Description
Leader of the group Networks and Optimization: Guido Schäfer.
In today’s society, complex systems surround us. From transport and traffic, to behavioral economics and operations management, realworld applications often demand that we identify simple, optimal solutions among a huge set of possibilities. Our research group Networks and Optimization (N&O) does fundamental research to tackle such challenging optimization problems.
We develop algorithmic methods to solve complex optimization problems efficiently. Our research provides efficient algorithms to some of the most challenging problems, for example, in planning, scheduling and routing. To come up with the best optimization algorithms, we combine and extend techniques from different disciplines in mathematics and computer science.
N&O covers a broad spectrum of optimization aspects. Our expertise ranges from discrete to continuous optimization and applies to centralized and decentralized settings. We focus on both problemspecific methods and universal toolkits to solve different types of optimization problems. The key in our investigations is to understand and exploit combinatorial structures, such as graphs, networks, lattices and matroids. Our research is of high scientific impact and contributes to various fields.
In several cooperations with industry partners, the algorithmic techniques that we develop in our group have proven useful to solve complex realworld problems. We are always interested in new algorithmic challenges arising in realworld applications and are open to new cooperations.
Watch our group video to get a glimpse of our activities.
Video about our collaboration with ProRail (in Dutch)
Vacancies
PhD student on the subject of Towards a Quantitative Theory of Integer Programming.
Centrum Wiskunde & Informatica (CWI) has a vacancy in the Networks & Optimization research group for a talented PhD student, on the subject of Towards a Quantitative Theory of Integer Programming.
Postdoc on the subject of Towards a Quantitative Theory of Integer Programming.
Centrum Wiskunde & Informatica (CWI) has a vacancy in the Networks & Optimization research group for a talented Postdoc, on the subject of Towards a Quantitative Theory of Integer Programming.
News
Network analysis reveals new information on tax treaties
Mathematical analysis of a data set collected by Centraal Planbureau (CPB), the Netherlands Bureau for Economic Policy Analysis, revealed new information on how bilateral tax treaties can be exploited to form ‘tax routes’ that minimize profit taxes.
Invited lecture Monique Laurent at ICM 2014
Monique Laurent will give an invited lecture at the International Congress of Mathematicians (ICM) 2014 on Wednesday 20 August in Seoul, Korea. It is a great honour to speak at ICM, the most important conference for mathematicians in the world, with thousands of participants and the award of the Fields Medals.
Bert Gerards on Solving Rota’s Conjecture in AMS Notices
Bert Gerards (CWI), Jim Geelen (University of Waterloo, Canada) and Geoff Whittle (Victoria University of Wellington, New Zealand) have published an article on Solving Rota’s Conjecture in the August issue of AMS Notices. The authors recently announced that they solved Rota's Conjecture after 15 years of work.
CWImathematician proves: altruism does not necessarily lead to better outcomes in game theory
New mathematical research shows that consideration for others does not always lead to the best outcome  that is, when it’s applied in game theory.
Members
Associated Members
Publications

de Klerk, E, & Laurent, M. (2019). Worstcase Examples for Lasserre’s Measure–Based Hierarchy for Polynomial Optimization on the Hypercube. Mathematics of Operations Research, 2019(November 5), 1–13. doi:10.1287/moor.2018.0983

Chen, J.J, Bansal, N, Chakraborty, S, & von der Brüggen, G. (2018). Packing sporadic realtime tasks on identical multiprocessor systems. In 29th International Symposium on Algorithms and Computation (pp. 71:1–71:14). doi:10.4230/LIPIcs.ISAAC.2018.71

Dadush, D.N, Nikolov, A, Talwar, K, & TomczakJaegermann, N. (2018). Balancing vectors in any norm. In Proceedings  Annual IEEE Symposium on Foundations of Computer Science, FOCS (pp. 1–10). doi:10.1109/FOCS.2018.00010

Carvalho Rodrigues, F, Schäfer, G, & Xavier, E.C. (2018). On the effectiveness of connection tolls in fair cost facility location games. In Proceedings of the 19th Italian Conference on Theoretical Computer Science (pp. 36–47).

van Heuven van Staereling, I.I. (2018). Tree decomposition methods for the periodic event scheduling problem. In OpenAccess Series in Informatics. doi:10.4230/OASIcs.ATMOS.2018.6

Carstens, C.J, & Kleer, P.S. (2018). Speeding up switch Markov chains for sampling bipartite graphs with given degree sequence. In Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques (APPROX/RANDOM 2018) (pp. 36:1–36:18). doi:10.4230/LIPIcs.APPROXRANDOM.2018.36

Amanatidis, G, Birmpas, G, & Markakis, V. (2018). Comparing approximate relaxations of envyfreeness. In IJCAI International Joint Conference on Artificial Intelligence (pp. 42–48).

Dadush, D.N, & Huiberts, S. (2018). A friendly smoothed analysis of the simplex method. In Proceedings of the Annual ACM Symposium on Theory of Computing (pp. 214–227). doi:10.1145/3188745.3188826

Bansal, N, Dadush, D.N, Garg, S, & Lovett, S. (2018). The GramSchmidt Walk: A Cure for the Banaszczyk Blues. In Proceedings of the 50th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2018 (pp. 587–597). doi:10.1145/3188745.3188850

Kamphorst, B. (2018, May 31). Heavytraffic behaviour of scheduling policies in queues.
Current projects with external funding

Continuous Methods in Discrete Optimization ()

Wiskundecluster DIAMANT ()

Smart Heuristic Problem Optimization

Approximation Algorithms, Quantum Information and Semidefinite Optimization (AQSO)

MixedInteger NonLinear Optimisation Applications (MINOA)

Polynomial Optimization, Efficiency through Moments and Algebra (POEMA)

Vóórkomen en voorkómen van incidenten op het spoor (PPS Prorail)

Towards a Quantitative Theory of Integer Programming (QIP)
Related partners

Alma Mater StudiorumUniversita di Bologna

AlpenAdriaUniversität Klagenfurt

CNR Pisa

CNRS

Dassault Systèmes B.V.

IBM

INRIA

Prorail

Rheinische FriedrichWilhelmus Universitaet Bonn

Technische Universität Dortmund

Tilburg University

Tromsø, Norway

Universita degli Studi di Firenze

Universität Konstanz

University of Birmingham