Netnews Filtering Server Department of Computer Science Stanford University Comments to: [log in to unmask] February 1994 ( A ) I N T R O D U C T I O N The Database Group at Stanford is providing a filtering service for NetNews articles. A user sends his profiles to the service, and will receive news articles relevant to his interests periodically. Communication to and from the service is via e-mail messages. A user's profile is, in the style of WAIS [1] queries, just a plain piece of English text; e.g., "object oriented programming," or "nba golden state warriors basketball." Based on the statistical distributions of the words in the articles, scores are given to evaluate how relevant they are to a profile. The highest possible score given to an article document is 100. The user can specify the minimum score for an article to be delivered. Below we first look at a sample message from the user and a sample notifica- tion from the service. Then we describe details of the user message format. ( B ) E X A M P L E A user who has sent this message to the service =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= From [log in to unmask] Fri Feb 19 21:48:24 1993 To: [log in to unmask] subscribe object oriented programming period 3 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= will receive periodically (every 3 days, as specified) notifications such as this one: =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= From [log in to unmask] Mon Feb 22 10:40:35 1993 To: [log in to unmask] Subscription 1: object oriented programming Article: comp.object.10836 From: [log in to unmask] (Eric Jul.) Subject: I-WOOOS'93 Call for Papers/Participation Score: 83 First 15 lines: CALL FOR PARTICIPATION 1993 INTERNATIONAL WORKSHOP ON OBJECT-ORIENTATION IN OPERATING SYSTEMS I-WOOOS '93 The Grove Park Inn and Country Club Ashville, North Carolina, U.S.A. December 9-10th, 1993 Sponsored by The IEEE Technical Committee on Operating Systems and Application Environments (TCOS) (pending) .... =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= The user can then request the whole article sent to him if he thinks it is relevant. ( C ) U S E R M E S S A G E F O R M A T User messages should be sent to [log in to unmask] The subject field of the message is ignored. Each message is a request to the service. Each request consists of a number of commands. Each command must start with a new line with no leading spaces. Continuation lines begin with a space or a tab. All commands are case-insensitive. Requests are associated with the return address of the user message. Service replies and deliveries will be sent to that address. The usages of the commands are as follows. ( C . 1 ) S u b s c r i b i n g To subscribe for articles, use these commands: SUBSCRIBE word word ... Subscribe for articles relevant to the profile specified by <word>'s. Maybe followed by PERIOD, EXPIRE, and THRESHOLD commands. PERIOD period (Optional - default 1 days) Specify <period> as the period between notifications (in days). EXPIRE days (Optional - default 9999 days) Specify <days> as the length (in days) for which the subscription is valid. THRESHOLD score (Optional - default 60) Specify <score> as the minimum score for an article to be relevant. The most relevant article is given a score of 100. <score> must an integer between 1 to 100. For example, to subscribe for articles related to "information filtering," valid for 200 days, send this: =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= % mail [log in to unmask] Subject: subscribe information filtering expire 200 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= The service will acknowledge your subscription, returning a subscription identifier (sid). ( C . 2 ) G e t t i n g A r t i c l e s After receiving notifications of articles that may be relevant to your interests, you may decide to see an article in its entirety. You can get the whole article with the GET command: GET article article ... Get the articles specified (by their article ids). For example, =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= % mail [log in to unmask] Subject: get news.announce.conferences.3670 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ( C . 3 ) R e l e v a n c e F e e d b a c k After reading the articles, you may find some that you like. You can provide feedback using these commands: FEEDBACK sid Provide feedback to subscription <sid>. LIKE article article ... Specify relevant article(s) by their ids. For example, this message says that article news.announce.conferences.3670 is relevant to subscription 1: =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= % mail [log in to unmask] Subject: feedback 1 like news.announce.conferences.3670 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= With feedback information, the service may be able to better match future articles against your subscriptions. ( C . 4 ) M a n a g i n g S u b s c r i p t i o n s You can manage your subscriptions with these commands: UPDATE sid Update subscription with id <sid>. Must be followed by one or more of PERIOD, EXPIRE, THRESHOLD (see C.1.), or PROFILE commands to specify the parameter(s) to be updated. PROFILE word word ... Specify the new profile for the UPDATE command. CANCEL sid Cancel subscription <sid>. LIST List all your subscriptions. For example, to update the period and the threshold of a subscription: =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= % mail [log in to unmask] Subject: update 3 period 1 threshold 60 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ( C . 5 ) S e a r c h F o r P a s t A r t i c l e s Besides providing the subscription service, the service also allows you to search for recent articles that are already in the database: SEARCH word word ... Do a search of the database with the given query. Maybe optionally followed by a THRESHOLD command to specify the minimum score for an article to be retrieved. For example, to search for articles related to "information filtering": =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= % mail [log in to unmask] Subject: search information filtering =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ( C . 6 ) O t h e r C o m m a n d s END End the request message. Useful for preventing the processing of signatures. HELP Get help information on server. ( D ) R E F E R E N C E S [1] B. Kahle, et al., "An Information System for Corporate Users: Wide Area Information Servers," ONLINE, Vol. 15, No. 5, p. 56-60, September 1991.