We describe the objectives and organization of the CLEF 2005 ad hoc track and discuss the main characteristics of the tasks offered to test monolingual, bilingual and multilingual textual document retrieval. The performance achieved for each task is presented and a preliminary analysis of results is given. The paper focuses in particular on the multilingual tasks which reused the test collection created in CLEF 2003 in an attempt to see if an improvement in system performance over time could be measured, and also to examine the multilingual results merging problem. Categories and Subject Descriptors H.3 [Information Storage and Retrieval]: H.3.1 Content Analysis and Indexing; H.3.3 Information Search and Retrieval; H.3.4 [Systems and Software]: Performance evaluation. General Terms Experimentation, Performance, Measurement, Algorithms. Additional Keywords and Phrases Multilingual Information Access, Cross-Language Information Retrieval
Giorgio Maria Di Nunzio, Nicola Ferro, Gareth J. F