Search (38 results, page 1 of 2)

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Footnote

Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.223-246.

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Date

22. 4.2007 10:07:51

Theme

Grundlagen u. Einführungen: Allgemeine Literatur

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Abstract

Digital libraries are sufficiently differnt from more traditional print on paper libraries to present a new set of parameters relating to the evaluation of its use. Discusses evaluation criteria, problems and methods relevant to the digital library environment

Source

Towards a worldwide library: a ten year forecast. Proceedings of the 19th International Essen Symposium, 23-26 Sept 1996. Ed.: A.H. Helal u. J.W. Weiss

Type

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Abstract

The results of 35 searches performed by users (end users) of an academic library (Illinois Stae University, Milner Library) in the ERIC databases on CD-ROM were compared with the results for the same topics achieved by an experienced education librarian and by a team of librarians. Recall ratios, precision ratios, and novelty ratios were calculated. Results show that the users, all faculty members or graduate students, found only about a third of the really important items. Suggests that library users are frequently misled into thinking that CD-ROM databases are easy to use and that the 'technology' guarantees satisfactory results.

Content

Im einzelnen wurden für den Patron (P), den Education Librarian (E) und das Team (T) folgende Zahlen ermittelt: Recall (P:32,3%; E:45,9%; T:53,8%); Precision (P:75,5%; E:71,4%; T:66,8%); Novelty (P:51,8%; E:61,6%; T:59,4%)

Type

a

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Footnote

Rez. in: JASIST 57(2006) no.1, S.144-145 (H. Saggion): "... This volume is a very valuable source of information for not only students and professionals in library and information science but also for individuals and institutions involved in knowledge management and organization activities. Because of its broad coverage of the information science topic, teachers will find the contents of this book useful for courses in the areas of information technology, digital as well as traditional libraries, and information science in general."

Theme

Grundlagen u. Einführungen: Allgemeine Literatur

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Footnote

Rez. in: JASIST 53(2002) no.4, S.321-322 (I. Fourie): "A substantial literature exists on artificial intelligence (AI) and expert systems in general, as well as in Library and Information Science (LIS). Many reports are over-confident and grossly exaggerate the power and potential of artificial intelligence (AI). This is especially true of the first phase of At, and to some extent also of the third phase that is stimulated by developments surrounding the Internet. The middle phase was mostly marked by disillusionment about the potential of Al and expert systems. The confusion around the promises made by AI and the lack of operational success, leaves managers of library and information services with the dilemma of distinguishing between worthwhile research reporting on operational projects and projects that exists only on paper or in the researchers' heads. It is very difficult to sieve between the two when working through the subject literature, and to distinguish between working technology/applications and wishful thinking. This might be one reason why working systems are sometimes ignored. According to Lancaster and Warner, library managers must also look much wider than the LIS literature to note new trends; this can, however, become a daunting task. Against this background the authors report on a study conducted with the support of the Special Libraries Association's Steven I. Goldspiel Memorial Research Grant. The objective of the study was to gain sufficient familiarity with the developments in Al and related technologies to make recommendations to the information service community on what can be applied, and what to expect in the near future. The intention therefore was to focus on systems that are actually operational, and systems that hold potential for the future. Since digital libraries seems an inevitable part of our future, applications concerning them features strongly in the final recommendations. The scope of AI in Library and Information Science depends on the interpretation of the concepts artificial intelligence and expert systems. "If a system has to `behave intelligently' (e.g. make inferences or learn from its mistakes) to qualify as having AI, few such systems exist in any application. On the other hand, if one accepts that a system exhibits AI if its does things that humans need intelligence to do, many more systems would qualify" (p. 107). One example is the field of subject indexing. The same would apply if a more relaxed definition of expert systems is applied as a system that "can help the non-expert perform some task at a level closer to that of an expert, whether or not all the essential components are in place" (p. 107). Most of the AI literature relevant to libraries falls in the field of expert systems. Lancaster and Warner identify (p. 6) expert systems as " a branch of artificial intelligence, even though very few expert systems exhibit true intelligence.""

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Theme

Grundlagen u. Einführungen: Allgemeine Literatur

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Theme

Grundlagen u. Einführungen: Allgemeine Literatur

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Theme

Grundlagen u. Einführungen: Allgemeine Literatur

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Abstract

In the monastic library of the Middle Ages, the librarian was essentially a curator, a preserver of collections. For most of history libarians were little more than custodians. The idea of a librarian as a provider of services rather than a collector or preserver of materials, did not emerge until late in the 19th century. Computer and telecommunications technologies have revolutionized the library and greatly expanded the horizons of the librarian. Discusses the ways in which technology has affected the library profession and discusses the role of the librarian in the future. The librarian will increasingly become an information intermediary or information consultant and some will be knowledge engineers involved in the design and construction of information systems and in electronic publishing

Type

a

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Abstract

Based partly on chapters in a forthcoming book 'Technology and Management in Library and Information Sciences' by F.W. Lancaster and B. Sandore. Some inportant functions of a research library operating largely in a networked digital environment are illustrated. The ability of artificial intelligence and expert system technologies to contribute to these functions is discussed, in the light of a report from the American Association for Artificial Intelligence, as well as experiences with these technologies in the library world and elsewhere

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a

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Abstract

A review of developments in electronic publishing over the last 25 years is followed by a report on a survey conducted, with directors of university libraries and other academic administrators, to determine attitudes toward a networked electronic approach to the publishing of research articles. A major conclusion is that academic administrators do not now consider the academic community well equipped to undertake an enterprise of this kind and would not give it high priority in the allocation of university resources

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Abstract

An overview of levels and approaches in the evalution of knowledge-based systems is presented. There is a need for empirical studies using objective criteria in advance of completing the technical evaluation of such systems. A methodology for this type of evaluation developed for a particular knowledge-based indexing system is presented. It is suggested that the proposed study may serve as a model for the design of any evaluation in which the results of existing intellectual procedures are compared with results achieved when these procedures are aided by use of an appropriate expert system

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a

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Abstract

F. W. Lancaster is known for his writing an the state of the art in librarylinformation science. His skill in identifying significant contributions and synthesizing literature in fields as diverse as online systems, vocabulary control, measurement and evaluation, and the paperless society have earned him esteem as a chronicler of information science. Equally deserving of repute is his own contribution to research in the discipline-his evaluation of the MEDLARS operating system. The MEDLARS study is notable for several reasons. It was the first large-scale application of retrieval experiment methodology to the evaluation of an actual operating system. As such, problems had to be faced that do not arise in laboratory-like conditions. One example is the problem of recall: how to determine, for a very large and dynamic database, the number of documents relevant to a given search request. By solving this problem and others attendant upon transferring an experimental methodology to the real world, Lancaster created a constructive procedure that could be used to improve the design and functioning of retrieval systems. The MEDLARS study is notable also for its contribution to our understanding of what constitutes a good index language and good indexing. The ideal retrieval system would be one that retrieves all and only relevant documents. The failures that occur in real operating systems, when a relevant document is not retrieved (a recall failure) or an irrelevant document is retrieved (a precision failure), can be analysed to assess the impact of various factors an the performance of the system. This is exactly what Lancaster did. He found both the MEDLARS indexing and the McSH index language to be significant factors affecting retrieval performance. The indexing, primarily because it was insufficiently exhaustive, explained a large number of recall failures. The index language, largely because of its insufficient specificity, accounted for a large number of precision failures. The purpose of identifying factors responsible for a system's failures is ultimately to improve the system. Unlike many user studies, the MEDLARS evaluation yielded recommendations that were eventually implemented.* Indexing exhaustivity was increased and the McSH index language was enriched with more specific terms and a larger entry vocabulary.

Source

Theory of subject analysis: a sourcebook. Ed.: L.M. Chan, et al

Type

a