A RE-UNIFICATION OF TWO COMPETING MODELS FOR DOCUMENT RETRIEVAL

Abstract

Two competing approaches for document retrieval were first identified by Robertson et al (Robertson, Maron et al. 1982) for probabilistic retrieval. We point out the corresponding two competing approaches for the Vector Space Model. In both the probabilistic and Vector Space models, only one of the two competing approaches has received significant research attention, because of the unavailibility of sufficient data to implement the second approach. Because it is now feasible to collect vast amounts of feedback data from users, both approaches are now possible. We therefore re-visit the question of a unification of both approaches, for both probabilistic and Vector Space models. This unification of approaches differs from that originally proposed in (Robertson, Maron et al. 1982), and offers unique advantages. Preliminary results of a simulation experiment are reported, and an outline is provided of an ongoing field study.