Search (60 results, page 3 of 3)

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Source

Proceedings of the 17th National Online Meeting 1996, New York, 14-16 May 1996. Ed.: M.E. Williams

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Theme

Verbale Doksprachen im Online-Retrieval

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Abstract

Considers intersearcher and intrasearcher consistency in the selection of search terms. Based on an empirical study where 22 searchers from 4 different types of search environments analyzed altogether 12 search requests of 4 different types in 2 separate test situations between which 2 months elapsed. Statistically very significant differences in consistency were found according to the types of search environments and search requests. Consistency was also considered according to the extent of the scope of search concept. At level I search terms were compared character by character. At level II different search terms were accepted as the same search concept with a rather simple evaluation of linguistic expressions. At level III, in addition to level II, the hierarchical approach of the search request was also controlled. At level IV different search terms were accepted as the same search concept with a broad interpretation of the search concept. Both intersearcher and intrasearcher consistency grew most immediately after a rather simple evaluation of linguistic impressions

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Source

Journal of information science. 22(1996) no.2, S.79-92

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Source

Information retrieval: new systems and current research. Proceedings of the 16th Research Colloquium of the British Computer Society Information Retrieval Specialist Group, Drymen, Scotland, 22-23 Mar 94. Ed.: R. Leon

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Abstract

Search statements in this revision process can be viewed as a 'move' in the overall search strategy. Very little is known about how end users develop and revise their search strategies. A study was conducted to analyse the moves made in 244 data base searches conducted by 26 medical students at the University of North Carolina at Chapel Hill. Students search INQUIRER, a data base of facts and concepts in microbiology. The searches were conducted during a 3-week period in spring 1990 and were recorded by the INQUIRER system. Each search statement was categorised, using Fidel's online searching moves (S. Online review 9(1985) S.61-74) and Bates' search tactics (s. JASIS 30(1979) S.205-214). Further analyses indicated that the most common moves were Browse/Specity, Select Exhaust, Intersect, and Vary, and that selection of moves varied by student and by problem. Analysis of search tactics (combinations of moves) identified 5 common search approaches. The results of this study have implcations for future research on search behaviours, for thedesign of system interfaces and data base structures, and for the training of end users

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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.

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Source

Proceedings of the 14th National Online Meeting 1993, New York, 4-6 May 1993. Ed.: M.E. Williams

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Abstract

Report of a study from the user's point of view, investigating the facility with which bibliographical material can be identified in a multidisciplinary field, the prospective for peace, from the University's resources. Searches (uniterm and relational) were effected using all available tools - OPACs, CD-ROM collections, online databases, manual catalogues, the Internet - both on the University's system and on national research institutions. Overall results returned a low rate of pertinence (1,86%). This is due not to lack of user search expertise but the lack of subject specific indexing coupled with using a MARC format

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Date

22. 9.1997 19:16:05

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Abstract

Die Einführung von CD-ROM Datenbanken als neue Informationstechnologie hat die Formen der Informationsgewinnung in bestimmten wissenschaftlichen Fachgebieten grundlegend geändert. Der Beitrag berichtet über Ergebnisse wissenschaftlicher Begleitforschung bei Endnutzerrecherchen in der CD-ROM-Version der Datenbank MEDLINE. Hierzu wurden drei verschiedene Erhebungen durchgeführt. Hiernach ist die überwiegende Zahl der Endnutzer (89,3%) mit dem jeweiligen Rechercheresultat zufrieden, wobei Benutzer mit geringer Rechercheerfahrung eine höhere Zufriedenheitsrate erreichen als Benutzer mit umfangreicheren Recherchekenntnissen. Die Gründe zur Nutzung von CD-ROM-Systemen resultieren voriwegend aus der klinischen Alltagsroutine oder täglichen Forschungspraxis, während vermittelte Online-Literatursuchen tendenziell häufiger im Zusammenhang mit einmaligen Ereignissen der wissenschaftlichen Aus- und Weiterbildung stehen. Die selbständige CD-ROM Literaturrecherche stellt für die befragten Ärzte und Wissenschaftler die bevorzugte Methode der Informationsgewinnung dar. Die analysierten Endnutzerrecherchen weisen allerdings Fehler und Defizite hinsichtlich einer optimalen Suchstrategie auf, die zu unbemerktn Informationsverlusten und zu Fehlbeurteilungen des wissenschaftlichen Kenntnisstandes führen

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Abstract

Discusses a retrieval study that focused on collection level archival records in the OCLC OLUC, made accessible through the EPIC online search system. Data were also collected from the local OPAC at North Carolina University at Chapel Hill (UNC-CH) in which UNC-CH produced OCLC records are loaded. The chief objective was to explore the retrieval environments in which a random sample of USMARC AMC records produced at UNC-CH were found: specifically to obtain a picture of the density of these databases in regard to each subject heading applied and, more generally, for each records. Key questions were: how many records would be retrieved for each subject heading attached to each of the records; and what was the nature of these subject headings vis a vis the numer of hits associated with them. Results show that large retrieval sets are a potential problem with national bibliographic utilities and that the local and national retrieval environments can vary greatly. The need for specifity in indexing is emphasized

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Abstract

Reports on a project undertaken to compare the behaviour of 2 types of users with 2 types of information retrieval interfaces. The user types were search process specialists and subject matter domain specialists with no prior online database search experience. The interfaces were native DIALOG, which uses a procedural language, and OAK, a largely menu based, hence non procedural language interface communicating with DIALOG. 3 types of data were recorded: logs automatically recorded by computer moitoring of all searches, results of structured interviews with subjects at the time of the searches, and results of focus group discussions after all project tasks were completed. The type of user was determined by a combination of prior training, objective in searching, and subject domain knowledge. The results show that the type of interface does affect performance and users adapt their behaviour to interfaces differently. Different combinations of search experience and domain knowledge will lead to different behaviour in use of an information retrieval system. Different kinds of users can best be served with different kinds of interfaces

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Abstract

Information seeking and provision does not occur in a vacuum, but is shaped and affected by the way that individuals convey regard for themselves and for each other. Reports 2 studies that explore the intersection between professional and personal or relational dimensions of intermediary practice during the research phase of a set of online computer search interactions that aim to address user information queries. The 1st study examines and compares, through an interpretative microanalytic approach, explicit and implicit situation defining assumptions contained in the initial talk, or opening moves, of 4 intermediaries in interaction with 2 users each. The 2nd study seeks to verify, quantitatively, interpretative claims developed in the 1st study through an analysis of intermediaries' use of pronouns in the course of their interactions with users. The specific patterns of results gained through this quantitiative study were consistent with those achieved interpretatively in the 1st study. The results of these studies are discussed within a proposed theoretic framework developed from the perspective of a constitutive theory of communication

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Source

Proceedings of the 13th National Online Meeting. Ed.: M.E. Williams

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Abstract

A software system has been developed which orders citations retrieved from an online database in terms of relevancy. The system resulted from an effort generated by NASA's Technology Utilization Program to create new advanced software tools to largely automate the process of determining relevancy of database citations retrieved to support large technology transfer studies. The ranking is based on the generation of an enriched vocabulary using lexical association methods, a user assessment of the vocabulary and a combination of the user assessment and the lexical metric. One of the key elements in relevancy ranking is the enriched vocabulary -the terms mst be both unique and descriptive. This paper examines term uniqueness. Six lexical association methods were employed to generate characteristic word indices. A limited subset of the terms - the highest 20,40,60 and 7,5% of the uniquess words - we compared and uniquess factors developed. Computational times were also measured. It was found that methods based on occurrences and signal produced virtually the same terms. The limited subset of terms producedby the exact and centroid discrimination value were also nearly identical. Unique terms sets were produced by teh occurrence, variance and discrimination value (centroid), An end-user evaluation showed that the generated terms were largely distinct and had values of word precision which were consistent with values of the search precision.

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Abstract

This study explores the relevance criteria and search strategies elementary school children applied when searching for information related to a class assignment in a school library setting. Students were interviewed on 2 occasions at different stages of the research process; field observations involved students thinking aloud to explain their search proceses and shadowing as students moved around the school library. Students performed searches on an online catalog, an electronic encyclopedia, an electronic magazine index, and the WWW. Results are presented for children selecting the topic, conducting the search, examining the results, and extracting relevant results. A total of 254 mentions of relevance criteria were identified, including 197 references to textual relevance criteria that were coded into 9 categories and 57 references to graphical relevance criteria that were coded into 5 categories. Students exhibited little concern for the authority of the textual and graphical information they found, based the majority of their relevance decisions for textual material on topicality, and identified information they found interesting. Students devoted a large portion of their research time to find pictures. Understanding the ways that children use electronic resources and the relevance criteria they apply has implications for information literacy training and for systems design

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Abstract

In order to compare the value of subject descriptors and title keywords as entries to subject searches, two studies were carried out. Both studies concentrated on monographs in the humanities and social sciences, held by the online public access catalogue of the National Library of the Netherlands. In the first study, a comparison was made by subject librarians between the subject descriptors and the title keywords of 475 records. They could express their opinion on a scale from 1 (descriptor is exactly or almost the same as word in title) to 7 (descriptor does not appear in title at all). It was concluded that 37 per cent of the records are considerably enhanced by a subject descriptor, and 49 per cent slightly or considerably enhanced. In the second study, subject librarians performed subject searches using title keywords and subject descriptors on the same topic. The relative recall amounted to 48 per cent and 86 per cent respectively. Failure analysis revealed the reasons why so many records that were found by subject descriptors were not found by title keywords. First, although completely meaningless titles hardly ever appear, the title of a publication does not always offer sufficient clues for title keyword searching. In those cases, descriptors may enhance the record of a publication. A second and even more important task of subject descriptors is controlling the vocabulary. Many relevant titles cannot be retrieved by title keyword searching because of the wide diversity of ways of expressing a topic. Descriptors take away the burden of vocabulary control from the user.