Search (4 results, page 1 of 1)

  • × year_i:[1960 TO 1970}
  • × theme_ss:"Retrievalstudien"
  1. Lancaster, F.W.: On the need for role indicators in postcoordinate retrieval systems (1968) 0.02 
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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
  2. Blagden, J.F.: How much noise in a role-free and link-free co-ordinate indexing system? (1966) 0.01 
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    Source
    Journal of documentation. 22(1966), S.203-209
  3. Good, I.J.: ¬The decision-theory approach to the evaluation of information-retrieval systems (1967) 0.01 
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    Abstract
    It is argued that the evaluation of information-retrieval systems should ultimately be based on the principle of rationality, the maximization of expected utility. In full generality this would involve an estimation of both the cost and value of a system, but the emphasis in this paper is on the problem of value, in terms of which the effiency of the system could be defined. One implication of the discussion is that it is not legitimate to superimpose the 2x2 contingency tables that refer to select/discarded and relevant/irrelevant, correspondending to each request,but it might be all right to superimpose them after applying a monotonic function to the entries. In particular, it is questionable whether a useful statistic is the ratio of the total number of relevant selected documents to the total number of relevant ones, over a sample of requests.
  4. Lesk, M.E.; Salton, G.: Relevance assements and retrieval system evaluation (1969) 0.01 
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    Abstract
    Two widerly used criteria for evaluating the effectiveness of information retrieval systems are, respectively, the recall and the precision. Since the determiniation of these measures is dependent on a distinction between documents which are relevant to a given query and documents which are not relevant to that query, it has sometimes been claimed that an accurate, generally valid evaluation cannot be based on recall and precision measure. A study was made to determine the effect of variations in relevance assesments do not produce significant variations in average recall and precision. It thus appears that properly computed recall and precision data may represent effectiveness indicators which are gemerally valid for many distinct user classes.

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