This paper reports the participation of the XLDB Group from the University of Lisbon in the CLEF 2006 ad-hoc monolingual and bilingual subtasks for Portuguese. We present our IR system and detail both the query expansion strategy and the weighting scheme. In the end, we describe our runs and analyse our performance. Categories and Subject Descriptors H.3 [Information Storage and Retrieval]: H.3.1 Content Analysis and Indexing; H.3.3 Information Search and Retrieval General Terms Design, Measurement, Experimentation Keywords Information Retrieval, Evaluation, CLEF, ad-hoc
Nuno Cardoso, Mário J. Silva, Bruno Martins