Proceedings of the 22nd international conference on Machine learning

This volume, which is also available online from http://www.machinelearning.org, contains the papers accepted for presentation at ICML-2005, the 22nd lnternational Conference on Machine Learning, which was held at the University of Bonn in Germany from August 7 to August 11, 2005. ICML is the annual conference of the lnternational Machine Learning Society (IMLS), and forms an international forum for the discussion and presentation of the latest results in the field of machine learning. This year, ICML was co-located with the 15th lnternational Conference on Inductive Logic Programming (ILP-2005), the proceedings of which are published by Springer Verlag in a separate volume. The papers in this volume were selected on the basis of a thorough review process. In the first round of reviewing, three program committee members produced individual reviews for a paper. Authors then had the opportunity to view those reviews and submit an author's reply to the reviewers. Led by the responsible area chair, the reviewers then engaged in a discussion about the paper, ultimately leading to the decision by the program chairs. In sum, of the 491 papers that were initially submitted, 62 were accepted immediately, and a further 81 were conditionally accepted and reconsidered after resubmission in a second round of reviewing. Of those 81 conditionally accepted papers, 72 were finally accepted, leading to a total of 134 accepted papers, which translates into an acceptance rate of 27.3 %. The author reply was a new feature of ICML this year, while the option of working with conditional accepts has already become a tradition. In addition to the presentations of the accepted papers, the ICML program included several other features. On the first and last day of the conference, 11 workshops and 6 tutorials on current topics of machine learning were held. For many of these, proceedings and/or presentation materials are available online from the ICML website. The other days of the conference each featured an invited talk by a prominent researcher as a program highlight. We were delighted that Johannes Gehrke of Cornell University, Michael Jordan of the University of California at Berkeley, and Gerhard Widmer of the University of Linz in Austria, agreed to deliver an invited talk. The abstracts of their talks are also published as part of these proceedings. Continuing a long standing tradition at ICML, all papers presented in a talk at the conference were also exhibited at evening poster sessions, giving everyone ample time to discuss the results in depth. In order to emphasize the co-location with ILP-2005, the program contained joint elements in both invited speakers, paper sessions, poster sessions, and tutorials. As usual, the scientific program was complemented by a social program, this time featuring an excursion to the scenic surroundings of the city of Bonn. During the conference best paper and best student paper awards were presented, the former being sponsored by NICTA, the later by the Machine Learning Journal.