TCD-DCU at TEL@CLEF 2009: Document Expansion, Query Translation and Language Modeling

For the multilingual ad-hoc document retrieval track (TEL@CLEF) at at the Cross-Language Retrieval Forum (CLEF) Trinity College Dublin and Dublin City University participated in collaboration. Our retrieval experiments focus on i) investigating document expansion using an entry vocabulary module, ii) translating queries with Google translate and a statistical MT system, and iii) investigating language modeling as a retrieval method. The major results are that the document expansion approach did not increase MAP; topic translation using the statistical MT system resulted in about 70% of the mean average precision (MAP) achieved when using Google translate for topic translation, and language modeling performs equally or better in comparison with BM25. The bilingual retrieval French and German to English experiments obtained 89% and 90% of the best MAP for monolingual English.