4.5.1 Connguration 5 Further Work 4.3 Model Enhancements

13 SURF is also currently based on a single user, stand-alone model, resulting in ineecient use of network resources. Articles may be retrieved from the NNTP server multiple times, once for each user. We are currently developing a version of SURF based on a client-server architecture which would allow us to optimize access to the news server by retrieving each article only once for multiple users. With the addition of user interface based client software, the prototype will also be much easier to use. In addition to a more complete user interface, we are investigating the addition of an email request interface to the server-based version of SURF. This would allow the large numbers of Internet users who have only basic Internet access (email and FTP capability) to use SURF as well. Users would forward their prooles to the server though the email interface, and receive the results via FTP. Any one of the increasing number of commercially available SGML viewers could be used to view the results. SURF could also beneet from a mechanism for relevance feedback 21]. This method has been shown to improve retrieval eeectiveness by allowing the user to specify which documents are of interest, and which are not. Terms from the relevant documents are added to the query vector, and terms from the non-relevant documents are removed. This has the eeect of \moving" the reformulated vector closer (in vector space) to that of relevant documents, providing more accurate retrieval results. 6 Conclusion This paper has described SURF, a prototype Netnews information lter, which uses well-known information retrieval techniques, and disseminates information as a set of hypertext-linked documents. In particular, we describe the techniques used to organize the ltered information, and methods by which the ltering process can be made to produce better results. Through extensive experience with the prototype, we have found SURF to complement the current suite of Internet resource discovery tools. Though still in the prototype stage, it has already become important facility for a number of group members. Current uses range from locating information for the maintenance of Internet mailing lists, to monitoring the performance of professional sports teams. With the addition of a number of usability enhancements, including a client-side user interface, we plan to release SURF to the general Internet community. 12 expressions speciied in the query vector. A relevance value is then computed for each article by measuring the …