International Journal of Data Warehousing & Mining, 3(2), 1-11, April-June 2007 1 Copyright © 2007, Idea Group Inc. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. is prohibited. AbstrAct The 10th Pacifc-Asia Conference on Knowledge Discovery and Data Mining (PAKDD) 2006 Data Mining Competition involved the problem of classifying mobile telecom network customers into second generation (2G) and third generation (3G) services, with the ultimate aim of identi- fying existing 2G network customers who had a high potential of switching to using the mobile operator’s new 3G mobile network and services. This paper discusses the background behind the preparation of the dataset, the choice of judging criteria incorporating both a quantitative measure of accuracy and a set of subjective qualitative assessments, and fnally a summary of the participation and results. We also highlight, in the report, interesting observations and fnd- ings from some of the participating teams. Keywords: balanced accuracy rate; data mining competition; qualitative assessment; Telco business problem IntroductIon The 10th PAKDD, a leading inter- national conference in the areas of data mining and knowledge discovery, was held in Singapore in May 2006. PAKDD, in association with the Singapore Institute of Statistics (SIS) and the Pattern Recognition and Machine Intelligence Association of Singapore (PREMIA), was able to organize a data mining competition for the confer- ence in 2006 based on a telecom operator business problem. 1 Although it was mentioned in the conference proceedings (Ng, Kisuregawa, Li, & Chang, 2006) that it was the frst time that PAKDD held such a competi- tion, actually there is record of one other competition using medical data organized during the Fourth PAKDD conference in Kyoto, Japan in 2000. In any case, the main point would be that PAKDD has not been holding regular annual competitions like the ACM SIGKDD International Conference on Knowledge Discovery and Data Min- ing (which has been organizing an annual KDD Cup since 1997 2 ) or the European Conference on Principles and Practice of Knowledge Discovery in Databases (with A Look back at the PAKdd data Mining competition 2006 Nathaniel B. Noriel, Singapore Institute of Statistics, Singapore Chew Lim Tan, National University of Singapore, Singapore IGI PUBLISHING This paper appears in the publication, International Journal of Data Warehousing and Mining, Volume 3, Issue 2 edited by David Taniar © 2007, IGI Global 701 E. Chocolate Avenue, Suite 200, Hershey PA 17033-1240, USA Tel: 717/533-8845; Fax 717/533-8661; URL-http://www.igi-pub.com ITJ3621