Using CONVECTIS, A Context Vector-Based Indexing System for TREC-4

This paper describes the experiments conducted using HNC's CONVECTIS Indexing System for the TREC-4 routing and filtering tasks. An overview of CONVECTIS is describes as well as the modifications to the system to perform both the routing and the filtering tasks. In prior participation in TREC the MatchPlus Context Vector Retrieval System was utilized. The MatchPlus system relied on Context Vectors as well as a broad Boolean filter for optimal performance. The Boolean filter created a large subset of likely relevant documents which were then ranked using the Context Vector technique. For TREC-4, as an experiment, the Boolean filter was not used. Instead, CONVECTIS was used which relied only on judged documents as prototypes of desired behavior. Preliminary results of these experiments are presented.