AUTOMATIC PARSING AND FACT RETRIEVAL: A COMMENT ON GRAMMAR, PARAPHRASE, AND MEANING,
Abstract
A major problem is to provide for automatic recognition of sameness of meaning in spite of structural differences so that when a request for factual information is processed, any of the possible paraphrases of an answer will be retrieved from a natural language text. The RAND parsing grammar has been extended and refined so that identical labels are attached to comparable elements of structurally different paraphrases, such as the active-passive pair, 'X commands the third fleet' and 'The third fleet is commanded by X.' The sentences are first parsed automatically; then the output of the PARSE routine is fed into a subroutine called FLAG, which attaches labels that make the sameness of meaning explicit. The labels are attached by using coded information derived from the rules applied in the course of parsing the sentences. A sample of the output from the PARSE and FLAG routines shows how the differences in structure are resolved automatically and how the labels are attached that make possible the automatic retrieval of both sentences in response to a single relevant request. It is shown in detail how interrogative sentences also may be recognized as paraphrases of a single request and how the output from their processing can be used as input to a retrieval search. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1964
- Accession Number
- AD0432036
Entities
People
- Jane J. Robinson
Organizations
- RAND Corporation