### Research Focus

Algorithmic game theory is an emerging new area of designing systems and algorithms for selfish users. My research focuses on algorithms and games on graphs or networks. I am mostly interested in designing algorithms and games that provide provably close-to-optimal results.

### Publications

Network Games and extensions

- T. Roughgarden and E. Tardos: How Bad is Selfish Routing? Journal of the ACM, 2002, Volume 49 , Issue 2. Preliminary version has appeared in the Proceedings of the 41st Annual IEEE Symposium on the Foundations of Computer Science, 2000.
- T. Roughgarden and E. Tardos:
*Bounding the Inefficiency of Equilibria in Nonatomic Congestion Games. Games and Economic Behaviour, Volume 47, Issue 2, May 2004, Pages 389-403.* - H. Lin, T. Roughgarden, and E. Tardos, Bounding Braess's Paradox, Proceedings of the 15th Annual ACM-SIAM Symposium on Discrete Algorithms, 2004.
- H. Lin, T. Roughgarden, E. Tardos, and A. Walkover. Braess's Paradox, Fibonacci Numbers, and Exponential Inapproximability, in the 32nd International Colloquium on Automata, Languages and Programming (ICALP,05) July, 2005.
- E. Anshelevich, A. Dasgupta, É. Tardos, T. Wexler, Near-optimal network design with selfish agents, in the proceedings of the Annual ACM Symposium on the Theory of Computing, 2003.
- E. Anshelevich, A. Dasgupta, J. Kleinberg, E. Tardos, T. Wexler, and T. Roughgarden. The Price of Stability for Network Design with Fair Cost Allocation, Annual IEEE Symposium on Foundations of Computer Science, 2004.
- Eva Tardos. Network Games. Proceedings of the Annual ACM Symposium on Theory of Computing, 2004.
- Ara Hayrapetyan, Éva Tardos and Tom Wexler - A Network Pricing Game for Selfish Traffic Distributed Computing, (PODC'05 special issue).Preliminary version appeared in the Proceedings of

24th Annual ACM SIGACT-SIGOPS Symposium on Principles of Distributed Computing (PODC'05), July 2005. - Ara Hayrapetyan, Éva Tardos and Tom Wexler: Effect of Collusion in Congestion Games. Proceedings of the ACM Symposium on the Theory of Computing (STOC), 2006.
- L. Blume, D. Easley, J. Kleinberg and E. Tardos: Trading Networks with Price-Setting Agents to appear in EC'07.

Mechanism Design

- A. Archer and 'E. Tardos: Frugal Path mechanisms, to appear in Transaction on Algorithms. Preliminary version appeared in the Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms, 2002, pp. 991-999.
- A. Archer and E. Tardos: Truthful mechanisms for one-parameter agents,
*Proceedings of the 42nd IEEE Symposium on Foundations of Computer Science*(2001) 482-491. - A. Archer, Christos Papadimitriou, Kunal Talwar, Eva Tardos: An approximate truthful mechanism for combinatorial auctions with single parameter agents. Internet Mathematics, Volume 1 Issue 2, 2004. Prleiminary version appeared in the Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms, 2003, pp. 205 - 214.
- M. Pal and E. Tardos: Group Strategyproof Mechanisms via Primal-Dual Algorithms, in the Proceedings of the Annual IEEE Symposium on Foundations of Computer Science, 2003.
- A. Gupta, A. Srinivasan, and E. Tardos. Cost-Sharing Mechanisms for Network Design. Proceedings of APPROX 2004.

Social Networks

- David Kempe, Jon Kleinberg, Éva Tardos: Maximizing the Spread of Influence in a Social Network.
*Proceedings of KDD 2003, Washington DC*. - David Kempe, Jon Kleinberg, Éva Tardos: Influential Nodes in a Diffusion Model for Social Networks. In
*Proceedings of ICALP 2005, Lisboa, Portugal*.

Classification

- J. Kleinberg and E. Tardos. Approximation Algorithms for Classification Problems with Pairwise Relationships:

Metric Partitioning and Markov Random Fields, Journal of the ACM, 2002, Volume 49, Issue 5, pp, 616-639. Preliminary version has appeared in the Proceedings of the 40th Annual IEEE Symposium on the Foundations of Computer Science, 1999. - A. Gupta and E. Tardos: A Constant Factor Approximation Algorithm for a Class of Classification Problems, In the Proceedings of the ACM Symposium on the Theory of Computing, May 2000.
- A. Archer J. Fakcharoenphol, C. Harrelson, R. Krauthgamer, K. Talvar and E. Tardos: Approximate Classification via Earthmover Metrics, in the Proceedings of the 15th Annual ACM-SIAM Symposium on Discrete Algorithms, 2004.

Clustering and facility location

- Zoya Svitkina and Eva Tardos: Facility Location with Hierarchical Facility Costs. in the Proceedings of the 17th Annual ACM-SIAM Symposium on Discrete Algorithms, 2006.
- Martin Pál, Éva Tardos, Tom Wexler. Facility Location with Hard Capacities. In the Proceedings of the 42nd Annual IEEE Symposium on the Foundations of Computer Science, 2001.
- D. B. Shmoys, E. Tardos and K. Aardal. Approximation algorithms for the facility location problem.

In the Proc. of the 29th Annual ACM Symposium on the Theory of Computing, 1997, pp. 265-274. - M. Charikar, S. Guha, E. Tardos and D. Shmoys. A constant-factor approximation algorithm for the k-median problem. To appear in the JCSS, preliminary version has appeared in the Proc. of the 31st Annual ACM Symposium on the Theory of Computing, 1999, pp. 1-10.
- Ara Hayrapetyan, Chaitanya Swamy and Éva Tardos: Network Design for Information Networks, ACM-SIAM Symposium on Discrete Algorithms (SODA), 2005

Network Design

- M. Goemans, A. Goldberg, S. Plotkin, D. Shmoys, E. Tardos, and D. Williamson: Improved approximation algorithms for network design problems. In the proceeding of the 5th Annual ACM-SIAM Symposium on Discrete Algorithms, January 1994, pp. 223-232. ORIE TR-1116.
- V. Melkonian and E. Tardos. Approximation Algorithms for a Directed Network Design Problem.

In the Proceedings of the 7th International Integer Programming and Combinatorial Optimization Conference (IPCO'99), Graz, 1999. - Ara Hayrapetyan, Chaitanya Swamy and Éva Tardos - Network Design for Information Networks
- Zoya Svitkina and Éva Tardos: Facility Location with Hierarchical Facility Costs
**.**

Routing Disjoint Paths and Packets in Networks

- J. Kleinberg, Y. Rabani, and E. Tardos. Fairness in Routing and Load Balancing, In the Proceedings of the 40th Annual IEEE Symposium on the Foundations of Computer Science, 1999.
- J. Kleinberg and E. Tardos: Approximations for the Disjoint Paths Problem in High-Diameter Planar Networks, Journal of Computer and System Sciences STOC'95 special issue, vol 57, pp 61-73, 1998. Preliminary version has appeared in the Proceedings of the 27th Annual ACM Symposium on the Theory of Computing, 1995, pp. 26-35. ORIE TR-1121.
- J. Kleinberg and E. Tardos: Disjoint Paths in Densely Embedded Graphs, In the Proceedings of the 34th Annual IEEE Symposium on the Foundations of Computer Science, 1995, pp. 52-61.
- Y. Rabani and E. Tardos: Distributed Packet Switching in Arbitrary Networks, in the 28th ACM Symposium on Theory of Computing, May, 1996, pp. 366-376.

Scheduling

- D. Shmoys and E. Tardos, An approximation algorithm for the generalized assignment problem. Mathematical Programming A 62, 1993, 461-474. Preliminary version has appeared in the proceeding of the 4th Annual ACM-SIAM Symposium on Discrete Algorithms, January 1993.
- A. Goel, M. Henzinger, S. Plotkin, and E. Tardos. Scheduling Data Transfers in a Network and the Set Scheduling Problem In the Proc. of the 31st Annual ACM Symposium on the Theory of Computing, 1999, pp. 189-199.

Generalized Flow

- A. Goldberg, S. Plotkin, E. Tardos: Combinatorial algorithms for the generalized circulation problem, Mathematics of Operations Research, 16/2, 1991, 351-381. Preliminary version has appeared in the Proceedings of the 29th Annual IEEE Symposium on the Foundations of Computer Science (1988), 432-443.
- E. Tardos and K. Wayne. Simple Generalized Maximum Flow Algorithms. Proceedings of the 6th International Integer Programming and Combinatorial Optimization Conference (IPCO'98), Houston, 1998, pp. 310-324.

Packing and Covering Algorithms

- P. Klein, S. Plotkin, C. Stein and E. Tardos, Faster approximation algorithms for the unit capacity concurrent flow problem with applications to routing and finding sparse cuts. SIAM Journal on Computing, 23/3, 1994,. 466-487. Preliminary version has appeared in the proceedings of the 22nd Annual ACM Symposium on the Theory of Computing (1990), 310-321.
- T. Leighton, F. Makedon, S. Plotkin, C. Stein, E. Tardos, S. Tragoudas: Fast Approximation Algorithms for Multicommodity Flow Problems, Journal of Computer and System Sciences, 50 (STOC'91 special issue), 1995, pp. 228--243. Preliminary version has appeared in the Proceedings of the 23rd Annual ACM Symposium on the Theory of Computing (1991), 101-110.
- S.A. Plotkin, D. Shmoys, and E. Tardos, Fast approximation algorithms for fractional packing and covering problems, to appear in Mathematics of Operations Research. ORIE TR-999. Preliminary version has appeared in the Proceedings of the 32nd Annual IEEE Symposium on the Foundations of Computer Science (1991), 495-505.

Networks with transit times

- B. Hoppe and E. Tardos: Polynomial Time Algorithms for Some Evacuation Problems. In the proceeding of the 5th Annual ACM-SIAM Symposium on Discrete Algorithms, January 1994, pp. 433-441. .
- B. Hoppe and E. Tardos: The Quickest Transshipment Problem, journal version of the paper in the proceeding of the 6th Annual ACM-SIAM Symposium on Discrete Algorithms, 1995 pp. 512-521.
- L. Fleischer and E. Tardos. Efficient Continuous-Time Dynamic Network Flow Algorithms. Operations Research Letters 23 (1998) pp. 71-80.

Effective bandwidth

- J. Kleinberg, Y. Rabani and E. Tardos. Allocating Bandwidth for Bursty Connection. Journal version of the paper in the Proceedings of the 29th ACM Symposium on Theory of Computing, May, 1997, pp. 664-673.

Finding cuts in graphs

- S.A. Plotkin and E. Tardos, Improved Bounds on the Max-flow Min-cut Ratio for Multicommodity Flows. Combinatorica. Preliminary version has appeared in the Proceedings of the 25th Annual ACM Symposium on Theory of Computing, 1993, pp. 691-697.
- P. Klein, S. Plotkin, S. Rao and E. Tardos: Approximation Algorithms for Steiner and Directed Multicuts.
- Zoya Svitkina, and Eva Tardos. Min-Max Multiway Cut. Proceedings of APPROX 2004.

Separating cutting planes

- L. Fleischer and E. Tardos: Separating Maximally Violated Comb Inequalities in Planar Graphs, tech report version of the paper in the Proceedings of the 5th International Integer Programming and Combinatorial Optimization Conference (IPCO), June 1996, pp. 475-489.

Other Miscellaneous papers

- E. Tardos: The Gap Between Monotone and Non-Monotone Circuit Complexity is Exponential. Combinatorica, 1987, 7(4) 141-142.