  Methods for fusing document lists that were retrieved in response to a query
often utilize the retrieval scores and/or ranks of documents in the lists. We
present a novel fusion approach that is based on using, in addition,
information induced from inter-document similarities. Specifically, our methods
let similar documents from different lists provide relevance-status support to
each other. We use a graph-based method to model relevance-status propagation
between documents. The propagation is governed by inter-document-similarities
and by retrieval scores of documents in the lists. Empirical evaluation
demonstrates the effectiveness of our methods in fusing TREC runs. The
performance of our most effective methods transcends that of effective fusion
methods that utilize only retrieval scores or ranks.
