Publications in Journals

"Computing the Nadir Point for Multiobjective Discrete Optimization Problems," Journal of Global Optimization, Vol. 62, pp.79-99, 2015, with G. Kirlik.

"SVM Classification for Imbalanced Data Sets Using a Multiobjective Optimization Framework," Annals of Operations Research, Vol. 216, pp.191--203, 2014, with A. Aşkan (Öztürk).

"A New Algorithm for Generating All Non-dominated Solutions for Multiobjective Discrete Optimization Problems," European Journal of Operational Research, Vol. 232, pp. 479--488, 2014, with G. Kirlik.

"Exploring the trade-off between generalization and empirical errors in a one-norm SVM," European Journal of Operational Research, Vol. 218, pp. 667--675, 2012, with H. Aytuğ.

"SKU demand forecasting in the presence of promotions," Expert Systems with Applications, Vol. 36, pp. 12340-12348, 2009, with Özden Gür Ali, Tom Van Woensel and Jan Fransoo.

"Pricing and Lot Sizing Decisions in a Two-Echelon Supply Chain with Transportation Costs," OR Spektrum,, Vol. 31, pp. 629-650, 2009, with Can Yıldırmaz, Selçuk Karabatı.

"Using Support Vector Machines to Learn the Efficient Set in Multiple Objective Discrete Optimization,'' European Journal of Operational Research, Vol. 193, pp. 510-519, 2008, with H. Aytuğ.

"Single-Supplier/Multiple-Buyer Supply Chain Coordination with Vertical Information Sharing," European Journal of Operational Research, Vol.187, pp. 746-764, 2008, with Selçuk Karabatı.

"Assigning Cross-Trained Workers to Departments: A Two-Stage Optimization Model to Maximize Utility and Skill Improvement," European Journal of Operational Research, Vol. 176, pp. 1643-1658, 2007, with Selçuk Karabatı.

"The Multiobjective Discrete Optimization Problem: A Weighted Min-Max Two Stage Optimization Approach and a Bicriteria Algorithm," Management Science, Vol. 51, pp.1572-1581, 2005, with Panos Kouvelis.

"A Mixed-Integer Programming Approach to the Clustering Problem with An Application in Customer Segmentation," European Journal of Operational Research, Vol. 173(3), pp. 866-879, 2006, with Burcu Sağlam, F. Sibel Salman, and Metin Türkay.

"Algorithm Robust for the Bicriteria Discrete Optimization Problem: Heuristic Variations and Computational Evidence," Annals of Operations Research, Vol. 147, pp.71-85, 2006, with Panos Kouvelis.

"Assembly Line Balancing in a Mixed-Model Sequencing Environment," European Journal of Operational Research, Vol. 149, pp. 417-429 , 2003, with Selçuk Karabatı.

"A Procedure to Find Discrete Representations of the Efficient Set with Specified Coverage Errors," Operations Research, Vol. 51, pp. 427-436 , 2003.

"A Mixed Integer Programming Formulation for the 1-Maximin Problem," Journal of the Operational Research Society, Vol. 51, pp.371-375, 2000.

"Optimizing over the Efficient Set Using a Top-Down Search of Faces," Operations Research, Vol. 48, pp. 65-72, 2000.

"Measuring the Quality of Discrete Representations of Efficient Sets in Multiple Objective Mathematical Programming," Mathematical Programming, Vol. 87, pp.543-560, 2000.

"A Bicriteria Approach to the Two-Machine Flow Shop Scheduling Problem," European Journal of Operational Research, Vol.113, pp. 435-449, 1999, with Selçuk Karabatı.

"Part-Type Selection in Flexible Manufacturing Systems: A Bicriteria Approach with Due Dates," Journal of the Operational Research Society, Vol. 49, pp.659-669, 1998, with Meltem Denizel.

"Towards Finding Global Representations of the Efficient Set in Multiple Objective Mathematical Programming," Naval Research Logistics, vol. 44,pp.47-67, 1997, with H.P. Benson.

"Multiple Criteria Decision Making: An Overview of Solution Approaches," Industrial Engineering Journal, Vol. 7, pp.10-17, 1996 (in Turkish).

"An Algorithm Based on Facial Decomposition for Finding the Efficient Set in Multiple Objective Linear Programming," Operations Research Letters, Vol. 19, pp.87-94, 1996.

"A Finite Concave Minimization Algorithm Using Branch and Bound and Neighbor Generation," Journal of Global Optimization, Vol. 5, pp. 1-14, 1994, with H.P. Benson.

"Optimization over the Efficient Set: Four Special Cases," Journal of Optimization Theory and Applications, Vol. 80, pp. 3-18, 1994, with H.P. Benson.

"A Face Search Heuristic Algorithm for Optimizing over the Efficient Set," Naval Research Logistics, Vol. 40, pp. 103-116, 1993, with H.P. Benson.

Publications in Refereed Proceedings and Book Chapters

"Rustock Botnet and ASNs," TPRC 2011, with J. S. Quarterman and A.B. Whinston.

"Data, Reputation, and Certification Against Spam," Collaborative Data-Driven Security for High Performance Networks, Internet2, 17-18 August 2010, WUSTL, St. Louis, Missouri, U.S.A. with J.S. Quarterman, J. Reinikainen, E.V. Kumar, A.B. Whinston.

"A Game Theoretic Model and Empirical Analysis of Spammer Strategies," CEAS 2010, Redmond, WA, 13-14 July 2010, with M. Parameswaran, H. Rui, A.B. Whinston.

"A new gravity model with variable distance decay," EURO Mini Conference on Continuous Optimization and Knowledge-Based Technologies EUROPT'2008, , pp. 376-380, 2008, Vilnius, Lithuania, with M.Sandıkçıoğlu, Ö. Gür Ali.

"Multi-Objective Optimization and Decision Support Systems," in Encyclopedia of Optimization, (C. A. Floudas and P. M. Pardalos eds.), pp. 472-477, Kluwer, 2001.

"A Face Search Heuristic Method for Optimizing Over the Efficient Set," in Proceedings of the DSI Conference, Miami Beach, Florida, U.S.A., pp. 1091-1093, 1991, with H.P. Benson.

Working Papers and Other Ongoing Work

"Using Bilevel Programming to Find a Nondominated Solution in a Given Set and Generating Discrete Representations in Multiobjective Optimization," with Gökhan Kirlik, 2016.

"A Multiobjective Solution Method for Radiation Treatment Planning," with Gökhan Kirlik, H. Howard Zhang, 2016.

"Multiobjective Opitimization for Interwoven Systems," with H. Ishibuchi, K. Klamroth, S. Mostaghim, B. Naujoks, S. Poles, R. Purshouse, G. Rudolph, S. Ruzika, M. Wiecek, X. Yao, 2015.

"Optimal Screening Policies for Alzheimer's Disease," with Zehra Önen, 2015.

"Evaluating Healthcare System Efficiency of OECD Countries: A DEA-Based Study," with Z. Önen, 2015.

"Representations and Approximations of the Efficient Set in Bicriteria Discrete Optimization."

Presentations

"Two Methods for Finding Representations of the Nondominated Set in Multiobjective Optimization," 23rd International Conference on Multiple Criteria Decision Making, August 2015, Hamburg, Germany, with Gökhan Kirlik.

"Finding Representations of the Nondomoniated Set in Multiobjective Optimization," 22nd International Symposium on Mathematical Programming, July 2015, Pittsburgh, PA, USA, with Gökhan Kirlik.

"Exact and Representation Methods in Multiobjective Optimization,", Workshop on Recent Advances in Multiobjective Optimization, June 2015, Nantes, France.

"SVM Classification for Imbalanced Data Sets Using a Multiobjective Optimization Framework," 26th European Conference on Operational Research, July 2013, Rome, Italy, with A. Aşkan.

"Identifying Supported and Extreme Supported Nondominated Solutions and an Empirical Analysis of Their Representative Quality,", MCDM 2013, 22nd International Conference on Multiple Criteria Decision Making, June 2013, Malaga, Spain.

"Exploring the Trade-off Between Generalization and Empirical Errors in a One-norm SVM," 21st International Conference on Multiple Criteria Decision Making, June , 2011, Jyvaskyla, Finland, with Haldun Aytuğ.

"Analysis of Spamming Behavior at Different Aggregation Levels and Implications for IT Security," INFORMS 2010, Austin, TX, with Serpil Sayin, Manoj Parameswaran, John S. Quarterman, Andrew Whinston.

"The Effects of Technique and Data Complexity on the Quality of Forecasts: Predicting SKU Demand in A Grocery Retail Environment," Data Mining Meets Marketing, the McCombs School of Business, The University of Texas at Austin, August 2009, Austin, TX, USA, with Ö. Gür Ali, Tom van Woensel, Jan Fransoo.

"Çok Amaçlı Karar Süreçleri ve Modelleri (Multiple Objective Decision Processes and Models), Tutorial, National Meeting of the Operational Research Society of Turkey, June 2009, Bilkent, Ankara.

"Obtaining Representations and Approximations of the Efficient Set," INFORMS Optimization Conference, March 2008, Atlanta, Georgia, USA.

"Representations and Approximations of the Efficient Set in Bicriteria Discrete Optimization,'' 22nd European Conference on Operational Research, July 2007, Prague, Czech Republic.

"Exact and Heuristic Algorithms in Multiple Objective Discrete Optimization,'' Dagstuhl Seminar 06501: Practical Approaches to Multi-Objective Optimization, December 2006, Schloss Dagstuhl, Wadern, Germany.

"Using Support Vector Machines to Learn the Efficient Set in Multiple Objective Discrete Optimization,'' 7th International Conference on Multiple Objective Programming/ Goal Programming, June 2006, Tours, France, with Haldun Aytuğ.

"Learning the Efficient Set Using Support Vector Machines: Methodology and Potential Uses,'' 18th International Conference on Multiple Criteria Decision Making, June 2006, Chania, Crete, Greece, with Haldun Aytuğ.

"Assigning Cross-Trained Workers to Departments: An Optimization Model to Maximize Utility and Skill Improvement,'' 20th European Conference on Operational Research, July 2004, Rhodes, Greece, with S. Karabatı.

"Finding the Efficient Set of a Bicriteria Discrete Optimization Problem Using Algorithm Robust,'' EURO/INFORMS Joint International Meeting, July 2003, Istanbul, with P. Kouvelis.

"Robust Optimization and Multiobjective Optimization: Cross Utilization of Solution Methods,'' INFORMS Annual Meeting, Nov , 2002, San Jose, CA, with P. Kouvelis.

"Robustness and Efficiency: A Study of Relationships with Application to Discrete Optimization,'' 16th International Conference on Multiple Criteria Decision Making, Semmering, Austria, February 2002.

"On Finding Discrete Representations of the Efficient Set in Multiple Objective Mathematical Programming,'' EURO 2001, The European Operational Research Conference, Rotterdam, The Netherlands, July 2001.

"A Procedure to Find Discrete Representations of the Efficient Set with Specified Coverage Errors,'' 15th International Conference on Multiple Criteria Decision Making, METU, Ankara, July 2000.

"Representing the Efficient Set in Multiple Objective Mathematical Programming Problems,'' National Meeting of the Operational Research Society of Turkey, Ankara, June 1999 (in Turkish).

"Can Discrete Representations of the Efficient Set Be the Solution to a Multiple Objective Mathematical Programming Problem?'' Workshop on Efficiency Sets and Surfaces in Data Envelopment Analysis, Multiple Criteria Decision Making, and Finance: An Emphasis on New Exploratory Ideas, Helsinki School of Economics, Helsinki, Finland, February 1999.

"A Framework for Measuring the Quality of Discrete Representations of Efficient Sets,'' the 4th DAS (Decision Analysis and Support) Workshop on Multiple Criteria Support in Network Centric Organizations, Istanbul, September 1998. (organized by Yeditepe University, Istanbul, and International Institute for Applied Systems Analysis (IIASA), Laxenburg,Austria.)

"A Bicriteria Approach to Part-Type Selection in Flexible Manufacturing Systems,'' with Meltem Denizel, National Meeting of the Operational Research Society of Turkey, Ankara, June 1998 (in Turkish).

"Sequencing and Line Balancing in Mixed-model Assembly Lines,'' with Selçuk Karabatı, National Meeting of the Operational Research Society of Turkey, June 1998, Ankara (in Turkish).

"Measuring the Quality of Discrete Representations of Efficient Sets in Multiple Objective Mathematical Programming,'' 14th International Conference on Multiple Criteria Decision Making, Charlottesville, Virginia, USA, June 1998.

"Using Facial Decomposition for Optimizing over the Efficient Set,'' 13th International Conference on Multiple Criteria Decision Making, Cape Town, South Africa, January 1997.

"A Vector Optimization Method for Multiple Objective Linear Programming Based on Facial Decomposition,'' National Meeting of the Operational Research Society of Turkey, Istanbul, October 1996 (in Turkish).

"A Bicriteria Approach to the Two--Machine Flow Shop Problem,'' with Selçuk Karabatı, INFORMS New Orleans, U.S.A., November 1995.

"Optimizing Over the Efficient Set and Some Special Cases,'' National Meeting of the Operational Research Society of Turkey, Ankara, July 1995 (in Turkish.)

"An Algorithm Based on Facial Decomposition for Finding the Efficient Set in Multiple Objective Linear Programming,'' 12th International Conference on Multiple Criteria Decision Making, Hagen, Germany, June 1995.

"Multiple Criteria Decision Making,'' with Murat Kökksalan, National Meeting of the Operational Research Society of Turkey, Ankara, July 1994 (Tutorial, in Turkish.)

"Global Approaches to Representing the Efficient Set in Linear and Nonlinear Multiple Objective Optimization,'' with H. P. Benson, TIMS/ORSA Joint National Meeting, Boston, U.S.A., April 1994.

"Optimization over the Efficient Set: Four Special Cases,'' with H.P. Benson, TIMS/ORSA Joint National Meeting, Chicago, U.S.A., May 1993.

"Modification and Implementation of a Finite Branch and Bound Algorithm for Globally Solving Linearly Constrained Concave Minimization Problems,'' with H.P. Benson, ORSA/TIMS Joint National Meeting, Anaheim, California, U.S.A. November 1991 (refereed).

Graduate Students (MS, PhD)

Zehra Önen, Decision Modeling in Healthcare (ongoing, PhD)

Gökhan Kirlik, Exact and Representative Methods in Multiple Objective Optimization, PhD, 2014.

Aslı Pınar Yapıcı, Solving the Bicriteria Quadratic Knapsack Problem, 2013.

Ayşegül Öztürk, SVM classification for imbalanced datasets with multiobjective optimization framework, 2009.

Müge Sandıkçıoğlu, Store revenue prediction for store location evaluation using spatial interaction models, 2008 (co-supervisor Ö. Gür Ali).

Ayşegül Tunçelli, Forecasting simulated retail demand using statistical and data mining techniques, 2007 (co-supervisor Ö. Gür Ali).

Can Yıldırmaz, Pricing and lot sizing decisions in a two echelon supply chain with transportation costs, 2007 (co-supervisor S. Karabatı).

Eda Kaya, A new approach for project selection in service organizations considering workforce structure, 2006 (co-supervisor S. Karabatı).

Burcu Sağlam, A mixed integer programming approach to the clustering problem with an application in customer segmentation, 2005 (co-supervisors F.S. Salman and M. Türkay).

The IIAR Project

The IIAR (Incentives, Insurance and Reputation) project is building econometric models for economic incentives for Internet mail providers to do better about preventing and dealing with spam and botnets. This work involves game theoretic models and other formal mathematical models, together with statistical analysis and extensive empirical analysis of the Internet primarily based on anti-spam blocklists.

For more information, visit CREC web pages (McCombs School of Business, University of Texas at Austin).

Sponsored Research

TÜBİTAK 1001 Representation Methods for Finding the Nondominated Set in Multiobjective Optimization and Applications in Data Mining, 2012-2014.

TÜBİTAK BİDEB scholarship, sabbatical leave 2009-2010.

Modeling Churn in YKB Credit Card Business, with Ö. Gür Ali and H. Aytuğ, funded by YKB, 2008.

Forecasting Demand for SKUs in a Grocery Retail Chain, with Ö. Gür Ali, funded by KÜMPEM/MİGROS, 2006-2007.

Investigating Supported Efficient Solutions as a Representation of the Efficient Set, funded by TÜBİTAK 1002, 2006-2007.