Towards Risk-Aware Resource Selection

When searching multiple sources of information it is crucial to select only relevant sources for a given query, thus filtering out non-relevant content. This task is known as resource selection and is used in many areas of information retrieval such as federated and aggregated search, blog distillation, etc. Resource selection often operates with limited and incomplete data and, therefore, is associated with a certain risk of selecting non-relevant sources due to the uncertainty in the produced source ranking. Despite the large volume of research on resource selection, the problem of risk within resource selection has been rarely addressed. In this work we propose a resource selection method based on document score distribution models that supports estimation of uncertainty of produced source scores and results in a novel risk-aware resource selection technique. We analyze two distributed retrieval scenarios and show that many queries are risk-sensitive and, because of that, the proposed risk-aware approach provides a basis for significant improvements in resource selection performance.