RMIT University at INEX 2005: Ad Hoc Track

Different scenarios of XML retrieval are analysed in the INEX 2005 ad hoc track, which reflect different query interpretations and user behaviours that may be observed during XML retrieval. The RMIT University group’s participation in the INEX 2005 ad hoc track investigates these XML retrieval scenarios. Our runs follow a hybrid XML retrieval approach that combines three information retrieval models with two ways of identifying the appropriate element granularity and two XML-specific heuristics to rank the final answers. We observe different behaviours when applying our hybrid approach to the different retrieval scenarios, suggesting that the optimal retrieval parameters are highly dependent on the nature of the XML retrieval task. Importantly, we show that using structural hints in content only topics is a useful feature that leads to more precise search, but only when level of overlap among the retrieved elements is considered by the evaluation metric.