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Regazzi, J.J.: Evaluating indexing systems : a review after Cranfield (1980)
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Barraclough, E.D.: Opportunities for testing with online systems (1981)
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Keen, E.M.: Laboratory tests of manual systems (1981)
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Oddy, R.N.: Laboratory tests : automatic systems (1981)
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Saracevic, T.: On a method for studying the structure and nature of requests in information retrieval (1983)
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- Pages
- S.22-25
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Information retrieval experiment (1981)
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- Content
- Enthält die Beiträge: ROBERTSON, S.E.: The methodology of information retrieval experiment; RIJSBERGEN, C.J. van: Retrieval effectiveness; BELKIN, N.: Ineffable concepts in information retrieval; TAGUE, J.M.: The pragmatics of information retrieval experimentation; LANCASTER, F.W.: Evaluation within the environment of an operating information service; BARRACLOUGH, E.D.: Opportunities for testing with online systems; KEEN, M.E.: Laboratory tests of manual systems; ODDY, R.N.: Laboratory tests: automatic systems; HEINE, M.D.: Simulation, and simulation experiments; COOPER, W.S.: Gedanken experimentation: an alternative to traditional system testing?; SPARCK JONES, K.: Actual tests - retrieval system tests; EVANS, L.: An experiment: search strategy variation in SDI profiles; SALTON, G.: The Smart environment for retrieval system evaluation - advantage and problem areas
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Hodges, P.R.: Keyword in title indexes : effectiveness of retrieval in computer searches (1983)
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- Date
- 14. 3.1996 13:22:21
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Prasher, R.G.: Evaluation of indexing system (1989)
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- Abstract
- Describes information system and its various components-index file construstion, query formulation and searching. Discusses an indexing system, and brings out the need for its evaluation. Explains the concept of the efficiency of indexing systems and discusses factors which control this efficiency. Gives criteria for evaluation. Discusses recall and precision ratios, as also noise ratio, novelty ratio, and exhaustivity and specificity and the impact of each on the efficiency of indexing system. Mention also various steps for evaluation.
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Sievert, M.E.; McKinin, E.J.: Why full-text misses some relevant documents : an analysis of documents not retrieved by CCML or MEDIS (1989)
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- Date
- 9. 1.1996 10:22:31
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Cleverdon, C.W.; Mills, J.: ¬The testing of index language devices (1985)
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- Abstract
- A landmark event in the twentieth-century development of subject analysis theory was a retrieval experiment, begun in 1957, by Cyril Cleverdon, Librarian of the Cranfield Institute of Technology. For this work he received the Professional Award of the Special Libraries Association in 1962 and the Award of Merit of the American Society for Information Science in 1970. The objective of the experiment, called Cranfield I, was to test the ability of four indexing systems-UDC, Facet, Uniterm, and Alphabetic-Subject Headings-to retrieve material responsive to questions addressed to a collection of documents. The experiment was ambitious in scale, consisting of eighteen thousand documents and twelve hundred questions. Prior to Cranfield I, the question of what constitutes good indexing was approached subjectively and reference was made to assumptions in the form of principles that should be observed or user needs that should be met. Cranfield I was the first large-scale effort to use objective criteria for determining the parameters of good indexing. Its creative impetus was the definition of user satisfaction in terms of precision and recall. Out of the experiment emerged the definition of recall as the percentage of relevant documents retrieved and precision as the percentage of retrieved documents that were relevant. Operationalizing the concept of user satisfaction, that is, making it measurable, meant that it could be studied empirically and manipulated as a variable in mathematical equations. Much has been made of the fact that the experimental methodology of Cranfield I was seriously flawed. This is unfortunate as it tends to diminish Cleverdon's contribu tion, which was not methodological-such contributions can be left to benchmark researchers-but rather creative: the introduction of a new paradigm, one that proved to be eminently productive. The criticism leveled at the methodological shortcomings of Cranfield I underscored the need for more precise definitions of the variables involved in information retrieval. Particularly important was the need for a definition of the dependent variable index language. Like the definitions of precision and recall, that of index language provided a new way of looking at the indexing process. It was a re-visioning that stimulated research activity and led not only to a better understanding of indexing but also the design of better retrieval systems." Cranfield I was followed by Cranfield II. While Cranfield I was a wholesale comparison of four indexing "systems," Cranfield II aimed to single out various individual factors in index languages, called "indexing devices," and to measure how variations in these affected retrieval performance. The following selection represents the thinking at Cranfield midway between these two notable retrieval experiments.
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Lancaster, F.W.: Evaluating the performance of a large computerized information system (1985)
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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.
