An automatic query expansion (AQE) facility in an online catalogue was evaluated in an operational library setting. The Okapi experimental system had other features including: ranked output ‘best match’ keyword searching, automatic stemming, spelling normalisation and cross referencing as...

A major problem in using current best‐match methods in a filtering task is that of setting appropriate thresholds, which are required in order to force a binary decision on notifying a user of a document. We discuss methods for setting such thresholds and adapting them as a result of feedback...