Proceedings of the sixth ACM international conference on Web search and data mining

We are delighted to welcome you to the sixth ACM International Conference on Web Search and Data Mining (WSDM 2013) held on February 4-8, 2013, in Rome, Italy. As in the previous years, WSDM has attracted an impressive number of submissions tackling the most recent technical challenges in Web search and data mining, with an ever-growing interest in their social aspects. Now in its sixth year, the conference has reached maturity and has become a leading forum for disseminating the latest research developments in the field. We are happy to present here the proceedings of the conference. We received a total of 387 submissions (compared to 362 of the last year) from 36 countries and regions, out of which 73 were accepted for full paper publication in the proceedings, thus reaching an acceptance rate of 18.9% (compared to 20.7% of last year and 22.3% of two years ago). The authors of the accepted papers are from 20 countries, spanning four continents - making this a truly international forum. Oral presentation slots were allocated to all papers. Yet, in order to maintain the single-track model that most attendees prefer, we preserved this year the format with "spotlight" type and "plenary" type presentations. Out of the 73 accepted papers, 40 were assigned a "spotlight" slot, while 33 were assigned a plenary slot. The type of slot was chosen by the Program Chairs, mostly based on whether the topic and the content of the paper were best suited for a large group presentation or for a more focused and interactive "spotlight" style of presentation.