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  1. Xu, H.; Lancaster, F.W.: Redundancy and uniqueness of subject access points in online catalogs (1998) 0.02
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    Abstract
    Reports results of an analysis of 205 randomly selected records from the OCLC OLUC, to test the assumption that online catalogues have greatly improved subject searching capabilities, over card catalogues, by making other fields in the records searchable as subject access points (SAPs). Results showed considerable overlap (duplication) among the SAPs provided by the title, subject heading and classification number fields. On average, little more than 4 unique, unduplicated access points were found per record. Where title and classification number fields do add some access points not provided by subject headings, the increase is less than many librarians might be expected. Suggests that OPACs might outperform catalogues more in precision than in recall by allowing greater discrimination in searching; terms from different fields may be combined; titles offer greater specifity; searches can be limited by date, language or other criteria
  2. Lancaster, F.W.; Elliker, C.; Connell, T.H.: Subject analysis (1989) 0.00
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  3. Lancaster, F.W.; Connell, T.H.; Bishop, N.; McCowan, S.: Identifying barriers to effective subject access in library catalogs (1991) 0.00
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    Abstract
    51 subject searches were performed in an online catalog containing about 4,5 million records. Their success was judges in terms of lists of items, known to be relevant to the various topics, compiled by subject specialists (faculty members or authors of articles in specialized encyclopedias). Many of the items known to be relevant were not retrieved, even in very broad searches that sometimes retrieved several hundred records, and very little could be done to make them retrievable within the constraints of present cataloging practice. Librarians should recognize that library catalogs, as now implemented, offer only the most primitive of subject access and should seek to develop different types of subject access tools. - Vgl auch Letter (B.H. Weinberg) in: LTRS 36(1992) S.123-124.
  4. Lancaster, F.W.: Has technology improved subject access? (199?) 0.00
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  5. Lancaster, F.W.: On the need for role indicators in postcoordinate retrieval systems (1968) 0.00
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    Abstract
    A summary of the findings of various evaluations of role indicators is given. In general, the results have been negative in that little real evidence for the value of the devices has been presented. The need for roles in various subject fields and in very large systems, is discussed. They can only by justified on purely ecomic grounds - if the added cost involved in their use is offset by substantial reduction in the amount of output screening that must be done by the end user
  6. Su, S.-F.; Lancaster, F.W.: Evaluation of expert systems in reference service applications (1995) 0.00
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    Abstract
    Reports results of an evaluation of 2 expert systems designed for use in library reference services: ReferenceExpert (RE), developed by Houston University; and SourceFinder (SF), developed by Illinois University at Urbana-Champaign. The test group consisted of 60 graduate students at the initial stage of an intermediate level reference course. The evaluation involved test questions already used in an earlier study (College and research libraries 52(1991) no.5, S.454-465). Results indicated that: there was no significant difference between RE and SF students in the confidence they expressed regarding understanding of their test questions; no significant correlation was found between confidence in understanding the question and success in selecting appropriate sources; only 1/5 of the students agreed that the system they used could be considered 'intelligent'; the majority did not consider the system they used to be 'competent'; almost half agreed that the subject categories provided by the menus were too broad; a little more than half wer not satisfied with the information sources selected by their system; significantly more RE users than SF users agreed that they found the menu interface useful; and a keyword search capability was the feature most often mentioned as a needed system enhancement. Overall results indicated that current expert systems for the selection of reference sources cannot perform as well as experienced subject oriented reference librarians
  7. Lancaster, F.W.: Trends in subject indexing from 1957 to 2000 (1980) 0.00
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  8. Lancaster, F.W.: Evaluating the performance of a large computerized information system (1985) 0.00
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    Source
    Theory of subject analysis: a sourcebook. Ed.: L.M. Chan, et al