A Truncated Search Key Title Index

Abstract

An experiment showing that 3, 1, 1, 1 search keys derived from titles are sufficiently specific to be an efficient computerized, interactive index to a file of 135,938 MARC II records.This paper reports the findings of an experiment undertaken to design a title index to entries in the Ohio College Library Center's on-line shared cataloging system. Several large libraries participating in the center requested a title index because experience in those libraries had shown that the staff could locate entries in files more readily by title than by author and title. Users of large author-title catalogs have long been aware of great difficulties in finding entries in such catalogs. Since the center's computer program for producing an author-title index could be readily adapted to produce a title index, it was decided to add title access to the system.A previous paper has shown that truncated three-letter search keys derived from the first two words of a title are less specific than authortitle keys ( 1). Earlier work had revealed that addition of only the first letter of another word in a title improved specificity ( 2) . Therefore, the experiment was designed to test the specificity of keys consisting of the first three characters of the first non-English-article word of the title plus the first letter of a variable number of consecutive words.The experiment was also designed to produce an index that catalogers could use efficiently and that would operate efficiently in the computer system. It was assumed that the terminal user would have in hand the volume for which an entry was to be sought in the on-line catalog. The index was not to be designed for use by library users; subsequent experiments will be done to design an index for nonlibrarian users.Other investigations into computerized, derived-key title indexes include

An experiment using coordinate title word searches

“…Of the three experimental articles on truncated search keys produced at OCLC from 1970 to 1972, the third, and most important, was written by Philip L. Long and the present author (Long & Kilgour, 1972). We found that a 3, 1, 1, 1 title search key produced five or fewer listings 99.1% of the time from an online file of 135,938 entries.…”

The Universal Standard Book Number (USBN): a New Method for the Construction of Control Numbers for Bibliographical Records

“…8 no. 3 Kilgour (6,7,8,9) and his associates at the Ohio College Library Center have used truncated keys derived from both personal author and titles in order to retrieve entries from a large on-line file of catalogue records. These keys were successful for the purpose they were designed for.…”

The Shared Cataloging System of the Ohio College Library Center

“…The calculation of a home address comprises derivation of a search key from the record to be stored or retrieved and the hashing or randomizing of the key to obtain an integer, relative record address that is converted to a storage home address. The findings of OCLC research on search keys has been reported (9,10,11).…”