Experimentation with an information filtering system that combines cognitive and sociological filtering integrated with user stereotypes

A dual-method model and system for filtering and ranking relevance of infor mation is presented. One method is cognitive filtering, while the other is sociological filtering, which is integrated with user stereotypes. A protot ype system was developed to test the applicability of the model for filteri ng e-mail messages, and experiments were run to determine the effects of co mbining the two methods in various filtering strategies. Results reveal tha t although cognitive filtering alone is usually more effective than sociolo gical filtering alone, the combination of both methods yield better results than using each method individually. Ordinarily, the best filtering strate gies are achieved when the two methods are used in parallel, or when cognit ive filtering is the primary method, followed by sociological filtering. We conclude that the optimal filtering strategy of combining cognitive and so ciological filtering is stereotype dependent; i.e., for each user stereotyp e, there may be a specific combination of the cognitive and sociological fi ltering that yields best results. (C) 1999 Elsevier Science B.V. All rights reserved.