WAIS Searching

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WAIS Searching

Intro

Before the profileration of Web search engines the most useful searching tool available was WAIS. WAIS (Wide Area Information Service) provided full-text, (not just title), searching of databases of documents. WAIS databases were termed Sources, which were organized by topic.

Databases

The WAIS databases typically contained documents/articles upon a specific subject or area. The databases were indexed on article content (words). The WAIS databases were distributed throughout the Internet. Most WAIS databases were available to all Internet users.

Search Terms/Fields

WAIS searches were posed as Questions which contained the search criteria words. The pertinent topic terms to be located were specified by choosing specific WAIS Sources which contained the WAIS databases to be searched. The most powerful feature of WAIS was the full-text indexes it created. Every word in a document was fully indexed for fast comprehensive searching.

WAIS Results

A WAIS search returned documents' locations and weights. The normalized weights were document scores indicating the relevancy of a document match.

The weights for a best match had a score = 1000. The weight = Sum for each word [ ((count number of each word occurences) / (max num of each word occurences)) * (word 'worth' weight) ].

Features

WAIS searches provided no Boolean operators. Another limitation was the lack of document content filtering -- all searches utilized the full database index. The contextual ordering of search words was not taken into account. (That is, that order of the terms in the search query had no meaning to WAIS. WAIS did provide a unique feature termed: Relevance Feedback. Relevance feedback allowed words in located documents to be used as further search criteria.

WAIS Today

WAIS is still around today. It is actually the technology underlying some search engines. (The most likely engine based on WAIS is Lycos which reports very WAIS-like results.) There is still a free version of WAIS, FreeWAIS-sf, which one can use to index and search a large collection of documents.