Dublin City University at CLEF 2005: Experiments with the ImageCLEF St Andrew's Collection

The aim of the Dublin City University’s participation in the CLEF 2005 ImageCLEF St Andrew’s Collection task was to explore an alternative approach to exploiting text annotation and content-based retrieval in a novel combined way for pseudo relevance feedback (PRF). This method combines evidence from retrieved lists generated using textbased and content-based retrieval to determine which documents will be assumed relevant for the PRF process. Unfortunately the experimental results show that while standard text-based PRF improves upon a no feedback text-only baseline, at present our new approach to combining evidence from text-based and content-based retrieval does not give further improvement.