# Dr Justin Ward

## Senior Lecturer in Optimisation

Email: justin.ward@qmul.ac.uk
Telephone: 5065
Room Number: Mathematical Sciences Building, Room: MB-126
Website: http://www.maths.qmul.ac.uk/~jward/
Office Hours: Wednesday 10:00 PM-12:00PM by appointment

## Profile

Justin Ward is a Senior Lecturer in Optimisation at the School of Mathematics.  He specialises in the theory of computing and the design and analysis of algorithms for discrete optimisation problems.  His research focuses on obtaining approximation algorithms with provable guarantees for computationally hard optimisation problems.
Justin holds a PhD in computer science from the University of Toronto.  Before joining Queen Mary, he worked as a research fellow in the Department of Computer Science and the Centre for Discrete Mathematics and its Applications at the University of Warwick, and as a research scientist in the Theory of Computing Laboratory at EPFL.

## Publications

• Thiery T, Ward J (2022). Two-Sided Weak Submodularity for Matroid Constrained Optimization and Regression Proceedings of Machine Learning Research 35th Annual Conference on Learning Theory.
• Huang C-C, Ward J (2020). FPT-Algorithms for the \ell-Matchoid Problem with a Coverage Objective journal nameOfConference.
• Huang C-C, Thiery T, Ward J (2020). Improved Multi-Pass Streaming Algorithms for Submodular Maximization with Matroid Constraints journal Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques (APPROX/RANDOM 2020).
• Ahmadian S, Norouzi-Fard A, Svensson O et al. (2019). Better Guarantees for $k$-Means and Euclidean $k$-Median by Primal-Dual Algorithms SIAM Journal on Computing nameOfConference.
• Ahmadian S, Norouzi-Fard A, Svensson O et al. (2017). Better Guarantees for k-Means and Euclidean k-Median by Primal-Dual Algorithms 58th IEEE Annual Symposium on Foundations of Computer Science, FOCS 2017, Berkeley, CA, USA, October 15-17, 2017 2017 IEEE 58th Annual Symposium on Foundations of Computer Science (FOCS).
• Sviridenko M, Vondrák J, Ward J (2017). Optimal Approximation for Submodular and Supermodular Optimization with Bounded Curvature Mathematics of Operations Research nameOfConference.
• Makarychev K, Makarychev Y, Sviridenko M et al. (2016). A Bi-Criteria Approximation Algorithm for k-Means Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques, APPROX/RANDOM 2016, September 7-9, 2016, Paris, France nameOfConference.
• Barbosa RDP, Ene A, Nguyen HL et al. (2016). A New Framework for Distributed Submodular Maximization IEEE 57th Annual Symposium on Foundations of Computer Science, FOCS 2016, 9-11 October 2016, Hyatt Regency, New Brunswick, New Jersey, USA nameOfConference.
• Ward J, Zivny S (2016). Maximizing k-Submodular Functions and Beyond ACM Trans. Algorithms nameOfConference.
• Adamczyk M, Sviridenko M, Ward J (2016). Submodular Stochastic Probing on Matroids Math. Oper. Res. nameOfConference.
• Barbosa RDP, Ene A, Nguyen HL et al. (2015). The Power of Randomization: Distributed Submodular Maximization on Massive Datasets Proceedings of the 32nd International Conference on Machine Learning International Conference on Machine Learning Research.
• Sviridenko M, Vondrák J, Ward J (2015). Optimal approximation for submodular and supermodular optimization with bounded curvature Proceedings of the Twenty-Sixth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2015, San Diego, CA, USA, January 4-6, 2015 nameOfConference.
• Ward J, Zivny S (2014). Maximizing Bisubmodular and k-Submodular Functions Proceedings of the Twenty-Fifth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2014, Portland, Oregon, USA, January 5-7, 2014 nameOfConference.
• Filmus Y, Ward J (2014). Monotone Submodular Maximization over a Matroid via Non-Oblivious Local Search SIAM J. Comput. nameOfConference.
• Adamczyk M, Sviridenko M, Ward J (2014). Submodular Stochastic Probing on Matroids 31st International Symposium on Theoretical Aspects of Computer Science (STACS 2014), STACS 2014, March 5-8, 2014, Lyon, France nameOfConference.
• Sviridenko M, Ward J (2013). Large Neighborhood Local Search for the Maximum Set Packing Problem Automata, Languages, and Programming - 40th International Colloquium, ICALP 2013, Riga, Latvia, July 8-12, 2013, Proceedings, Part I nameOfConference.
• Ward J (2012). A (k+3)/2-approximation algorithm for monotone submodular k-set packing and general k-exchange systems 29th International Symposium on Theoretical Aspects of Computer Science, STACS 2012, February 29th - March 3rd, 2012, Paris, France nameOfConference.
• Filmus Y, Ward J (2012). A Tight Combinatorial Algorithm for Submodular Maximization Subject to a Matroid Constraint 53rd Annual IEEE Symposium on Foundations of Computer Science, FOCS 2012, New Brunswick, NJ, USA, October 20-23, 2012 nameOfConference.
• Filmus Y, Ward J (2012). The Power of Local Search: Maximum Coverage over a Matroid 29th International Symposium on Theoretical Aspects of Computer Science, STACS 2012, February 29th - March 3rd, 2012, Paris, France nameOfConference.
• Feldman M, Naor J, Schwartz R et al. (2011). Improved Approximations for k-Exchange Systems - (Extended Abstract) Algorithms - ESA 2011 - 19th Annual European Symposium, Saarbrücken, Germany, September 5-9, 2011. Proceedings nameOfConference.
• Ward J, Kimmell G, Alexander P (2005). Prufrock: a framework for constructing polytypic theorem provers 20th IEEE/ACM International Conference on Automated Software Engineering (ASE 2005), November 7-11, 2005, Long Beach, CA, USA nameOfConference.