[Picture]

That's me (Wojtek Kowalczyk)

Research

Projects

Teaching

Contact information

Email: wojtek@cs.vu.nl
Address: Faculty of Sciences, Vrije Universiteit Amsterdam,
De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands
Room: P-1.54
Phone: +31-20-598 7817
Fax: +31-20-598 7653

Latest Publications

  1. W. Kowalczyk, M. Jelasity, and A.E. Eiben. Towards Data Mining in Large and Fully Distributed Peer-to-Peer Overlay Networks. In T. Heskes, P. Lucas, L. Vuurpijl, and W. Wiegerinck, editors, Proceedings of the 15th Belgium-Netherlands Conference on Artificial Intelligence, 203-210 University of Nijmegen, 2003. Nominated for Best Paper Award.
  2. M. Jelasity, M. van Steen, and W. Kowalczyk. An approach to massively distributed aggregate computing on peer-to-peer networks. Proceedings of the 12th Euromicro Conference on Parallel, Distributed and Network-based Processing, 200-207. IEEE Computer Society, 2004.
  3. M. Jelasity, W. Kowalczyk, and M. van Steen. Newscast Computing. Submitted
  4. W. Kowalczyk. Inverting Multi-layer Perceptrons is Easy. In T. Heskes, P. Lucas, L. Vuurpijl, and W. Wiegerinck, editors, Proceedings of the 15th Belgium-Netherlands Conference on Artificial Intelligence, 195-202, University of Nijmegen, 2003. Nominated for Best Paper Award.
  5. W. Kowalczyk. An Approximate Algorithm for Reverse Engineering of Multi-layer Perceptrons. In F. Coenen, A. Preece, and A.L. Macintosh, editors, Research and Development in Intelligent Systems XX, Proceedings of AI 2003, the 23rd SGAI International Conference on Innovative Techniques and Applications of Artificial Intelligence, 55-66, Springer, 2003.
  6. W. Kowalczyk. Heuristics for building scorecard trees. Credit Scoring and Credit Control VIII, University of Edinburgh, Working Papers, September 2003.

Older Publications

1996-1999

[1] Kowalczyk, W., An Algorithm for training multilayer networks on non-numeric data, Proceedings of the 4th European Symposium On Artificial Neural Networks, Bruges (Belgium), 1996, pp. 279-284.

[2] Kowalczyk, W., TRANCE: a Tool for Rough data ANalysis, Classification, and clustEring. In Proceedings of the 4th International Workshop on Rough Sets, Fuzzy Sets and Machine Discovery, RSFD'96.Tokyo, November 6-8, 1996. Tokyo University Press.

[3] Kowalczyk, W. (1996). Analyzing temporal patterns with rough sets. In H.-J. Zimmermann (ed.), Proceedings of the 4th European Congress on Intelligent Techniques and Soft Computing, Verlag Mainz, Aachen. (pp. 139-143).

[4] Kowalczyk, W. (1996). Analyzing Data with Rough Data Models. In Proceedings of the 6th Belgian-Dutch Conference on Machine Learning, Maastricht, pp. 127-136.

[5] A.E. Eiben, T.J. Euverman, W. Kowalczyk, E. Peelen, F. Slisser and J.A.M. Wesseling. Comparing Adaptive and Traditional Techniques for Direct Marketing, in H.-J. Zimmermann (ed.), Proceedings of the 4th European Congress on Intelligent Techniques and Soft Computing, Verlag Mainz, Aachen, pp. 434-437, 1996.

[6] W. Kowalczyk, Analyzing signals with AI techniques: two case studies. To be published in Proceedings of the First Polish Conference on Theory and Applications of Artificial Intelligence, Lodz, December 19-21. This paper is an adopted version of my unpublished contribution to the International Competition for Signal Analysis and Processing by Intelligent Techniques, presented during the EUFIT'96 conference in Aachen, Sept. 96.

[7] Jüngen, F.J. and W. Kowalczyk, Approximate Algorithms for Maximum Utility Problems, in Proceedings of the Principles and Practice of Constraint Programming Conference, (Freuder, E.C. editor), Lecture Notes in Computer Science 1118, Springer Verlag, 1996, pp.547-548.

[8] Jüngen, F.J. and W. Kowalczyk, Approximate Algorithms for Generalized Maximum Utility Problems, in Workshop Notes of the ECAI96 Workshop on Non-standard Constraint Processing, (Hower, W. and Ruttkay, Zs. editors), Budapest, 1996, pp. 25-36.

[9] Jüngen, F.J. and W. Kowalczyk, Finding Approximate Solutions for Maximum Utility Problems with an Expected Utility-based Heuristic, in Proceedings of the Eight Dutch Conference on Artificial Intelligence}, (Meyer, J.-J.Ch. and Van der Gaag, L.C. editors), Utrecht, 1996, pp. 235-244 (Best Paper Award).

[10] Kowalczyk, W. and Slisser, F. Analyzing customer retention with rough data models. In Proceedings of the 1st European Symposium on Principles of Data Mining and Knowledge Discovery, PKDD'97, Trondheim, Norway, Lecture Notes in AI 1263, Springer-Verlag, pp. 4-13.

[11] Kowalczyk, W. and Slisser, F. (1997). Analyzing customer behaviour with rough data models. In Proceedings of the Ninth Dutch Conference on Artificial Intelligence, NAIC'97, University of Antwerp, pp. 37-46.

[12] Jahns, G., Kowalczyk, W., Walter, K. An application of sound processing techniques for determining condition of cows, Published in Proceedings of the 4st International Workshop on Systems, Signals and Image Processing, IWSSP'97, Poznan, Poland, (M. Domanski and R. Stasinski ed.), Poznan University of Technology, ISBN 83-906074-1-7, pp. 105-109.

[13] Jahns, G.; W. Kowalczyk and K. Walter. Sound analysis to recognize different animals. Proceedings of the Mathematical and Control applications in agriculture & horticulture (IFAC/ISHS), (Munack, A. and Tantau, H.-J. eds.) Hannover, Pergamon Press, 1997, pp 169-173.

[14] Jahns, G.; W. Kowalczyk and K. Walter. Identification of animals and animal conditions by sound analysis. Proceedings of the Joint International Conference on Agriculture, Dhaka, 15.-18.Dec.97, page 670-675.

[15] Kowalczyk, W. (1998). Rough Data Modeling: a new technique for analyzing data. In: L. Polkowski and A. Skowron (eds.) Rough Sets in Knowledge Discovery, pp. 400-421, Physica--Verlag, 1998.

[16] F.J. Jüngen and W. Kowalczyk. Approximate algorithms for generalized maximum utility problems. Journal of Experimental and Theoretical Artificial Intelligence, vol. 10, (1998), 49-62.

[17] Kowalczyk, W. and Piasta, Z. (1998). Rough sets-inspired approach to knowledge discovery in business databases. In Proceedings of The Second Pacific-Asia Conference on Knowledge Discovery and Data Mining, PAKDD-98, Melbourne, Lecture Notes in Artificial Intelligence, vol. 1394, Springer-Verlag, 186-197.

[18] Kowalczyk, W. An Empirical Evaluation of the Accuracy of Rough Data Models. In Proceedings of the 7th International Conference on Information Processing and Management of Uncertainty in Knowledge-based Systems, IPMU'98, Paris, La Sorbonne, (1998), pp. 1534--1538.

[19] G. Jahns, W. Kowalczyk, K. Walter. Sound Analysis to Recognize Individuals and Animal Conditions. 13th International Congress on Agricultural Engineering, 2-6 February 1998, Rabat, Morocco, pp. 69-76.

[20] A.E. Eiben, T.J. Euverman, W. Kowalczyk, F. Slisser. Modeling Customer Retention with Statistical techniques, Rough Data Models, and Genetic Programming, in S.K.Pal and A. Skowron (eds.), Rough Fuzzy Hybridization: A New Trend in Decision-Making, Springer Verlag, pp. 330-345, 1998.

[21] Kowalczyk, W. An Empirical Evaluation of Performance of Rough Data Models. To appear in The International Journal of Intelligent Systems (1999).

 

1993-95

[1] Kowalczyk, W., Incremental Learning From Decision Tables: A Neural Network Approach, in Proceedings of The Third International Workshop on Rough Sets and Soft Computing, the Society for Computer Simulation, San Diego, 1995, pp. 324-331.

[2] Jüngen, F.J., Kowalczyk, W., An Intelligent Interactive Project Management Support System, European Journal of Operational Research, 84, 1995, pp. 60-81.

[3] Eiben, A.E., Euverman, T.J., Kowalczyk, W., Peelen, E., Slisser, F., Wesseling, J.A.M., Genetic Algorithms and Neural Networks vs. Statistical Techniques: A Case Study in Marketing, in Proceedings of the 5'th International Workshop on Parallel Applications in Statistics and Economics, PASE'95, ETH Zurich.

[4] Eiben, A.E., Euverman, T.J., Kowalczyk, W., Peelen, E., Slisser, F., Wesseling, J.A.M., Response modelling en doelgroepselectie in een business-to-business markt. In Toepassing van neurale netwerken in marketing, Henry Stewart Conference Studies/ Living Stones Foundation, Amsterdam, 1995

 

1989-92

[1] Kowalczyk, W., Treur , J., On the use of a formalized generic task model in knowledge acquisition, in: B.J. Wielinga et al. (Eds.): Current Trends in Knowledge Acquisition (Proceedings EKAW-90), pp. 198-221, IOS Press, Amsterdam, 1990.

[2] Geelen, P.A., Kowalczyk, W. (1990), Een Kennissysteeem voor Routing van Internationale Blanco Betalingsopdrachten, in Proceedings of the "AI Toepassingen'90" Conference, Kerkrade, 1990, pp. 51-58 (Best Paper Award).

[3] S.Bakker, F.J. Jungen, W. Kowalczyk, G.J. Moses, Towards Integration of OR and AI. A case study: Critical Path Method, Proceedings Computing Science in the Netherlands, CSN-91, pp. 47-61.

[4] W. Kowalczyk, P.H.G. van Langen, T.P.J. van Rijn, Y.H. Tan, A generic task-model for dynamic project scheduling, (in Dutch) Proc. Dutch Conference on AI Applications, AIT-91, Amsterdam, pp. 15-26

[5] Geelen P.A., Kowalczyk W., A Knowledge-Based System for the Routing of International Payments, Proc. 12th International Avignon Conference on Artificial Intelligence, Expert systems and Natural Language, Avignon-92, 1992, Vol. 2, pp. 669-677

[6] Kowalczyk W., Neural Networks in Knowledge-based Systems, Proc. of the 2nd Symposium on Neural Networks, Nijmegen 1992, pp. 47-49

 

1982-88

[1] Kowalczyk, W., (1982), A sufficient condition for the consistency of P=NP with Peano Arithmetic, Fundamenta Informaticae, V.2, 233-245.

[2] Kowalczyk, W. (1984), Some connections between presentability of complexity classes and the power of formal systems of reasoning, Proceedings of the 11th Symposium on Mathematical Foundations of Computer Science, Lecture Notes in Computer Science, 176, 364-369.

[3] Kowalczyk, W., (1984), On the effectiveness of some operations on algorithms, Proceedings of the 5th Symposium on Computation Theory, Lecture Notes in Computer Science, 208, 127-133.

[4] Kowalczyk, W., Urzyczyn, P., (1987), Verification of programs with higher order arrays, in Proceedings of FCT'87 (Symposium on Fundamentals of Computation Theory), Lecture Notes In Computer Science, 278.

[5] Kowalczyk, W., (1989), On the time and space requirements for pushdown automata of higher order, Fundamenta Informaticae, 1989.

[6] Kowalczyk, W., Niwinski, D., Tiuryn, J., (1989), A generalization of Cook's Auxiliary-Pushdown-Automata Theorem, Fundamenta Informaticae, 1989.

[7] Kowalczyk, W. (1989), Complexity of decision problems under incomplete information, Proceedings of the 14th Symposium on Mathematical Foundations of Computer Science, Lecture Notes in Computer Science, 379, 364-369.