Advances in information retrieval : 29th European Conference on IR Research ECIR 2007 Rome Italy April 2 5 2007 ; proceedings This book constitutes the refereed proceedings of the 29th annual European Conference on Information Retrieval Research ECIR 2007 held in Rome Italy in April 2007. The 42 revised full papers and 19 revised short papers presented together with 3 keynote talks and 21 poster papers were carefully reviewed and selected from 220 article submissions and 72 poster paper submissions. The papers are organized in topical sections on theory and design efficiency peer to peer networks result merging queries relevance feedback evaluation classification and clustering filtering topic identification expert finding XML IR Web IR and multimedia IR. Written for:Researchers and professionals Keywords: IR Web query mining Web search XML retrieval classification clustering collaborative Web searches collaborative filtering cross language retrieval distributed IR document retrieval image retrieval information extraction information retrieval multimedia retrieval question answering results merging semantic orientation similarity search text mining