Search (14 results, page 1 of 1)

  • × author_ss:"Saracevic, T."
  1. Saracevic, T.: Effects of inconsistent relevance judgments on information retrieval test results : a historical perspective (2008) 0.02
    0.018229576 = product of:
      0.0729183 = sum of:
        0.023624292 = weight(_text_:libraries in 5585) [ClassicSimilarity], result of:
          0.023624292 = score(doc=5585,freq=2.0), product of:
            0.13017908 = queryWeight, product of:
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.03962768 = queryNorm
            0.18147534 = fieldWeight in 5585, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5585)
        0.049294014 = weight(_text_:studies in 5585) [ClassicSimilarity], result of:
          0.049294014 = score(doc=5585,freq=4.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.3117402 = fieldWeight in 5585, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5585)
      0.25 = coord(2/8)
    
    Abstract
    The main objective of information retrieval (IR) systems is to retrieve information or information objects relevant to user requests and possible needs. In IR tests, retrieval effectiveness is established by comparing IR systems retrievals (systems relevance) with users' or user surrogates' assessments (user relevance), where user relevance is treated as the gold standard for performance evaluation. Relevance is a human notion, and establishing relevance by humans is fraught with a number of problems-inconsistency in judgment being one of them. The aim of this critical review is to explore the relationship between relevance on the one hand and testing of IR systems and procedures on the other. Critics of IR tests raised the issue of validity of the IR tests because they were based on relevance judgments that are inconsistent. This review traces and synthesizes experimental studies dealing with (1) inconsistency of relevance judgments by people, (2) effects of such inconsistency on results of IR tests and (3) reasons for retrieval failures. A historical context for these studies and for IR testing is provided including an assessment of Lancaster's (1969) evaluation of MEDLARS and its unique place in the history of IR evaluation.
    Content
    Beitrag in einem Themenheft 'The Influence of F. W. Lancaster on Information Science and on Libraries', das als Festschrift für F.W. Lancaster deklariert ist.
  2. Saracevic, T.; Kantor, P.B.: Studying the value of library and information services : Part II: Methodology and taxonomy (1997) 0.02
    0.017544128 = product of:
      0.07017651 = sum of:
        0.02834915 = weight(_text_:libraries in 353) [ClassicSimilarity], result of:
          0.02834915 = score(doc=353,freq=2.0), product of:
            0.13017908 = queryWeight, product of:
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.03962768 = queryNorm
            0.2177704 = fieldWeight in 353, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.046875 = fieldNorm(doc=353)
        0.04182736 = weight(_text_:studies in 353) [ClassicSimilarity], result of:
          0.04182736 = score(doc=353,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 353, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=353)
      0.25 = coord(2/8)
    
    Abstract
    Details with specifics of the study: importance of taxonomy; the method used for gathering data on user assessments of value in 5 research libraries, involving 18 services and 528 interviews with users; development and presentation of the taxonomy; and statistics and tests of the taxonomy. A novel aspect is the division of value of information services into 3 general classes or facets; reasons for use of a service in the given instance; quality of interaction (use) related to that service; and worth, benefits, or implications of subsequent results from use
    Footnote
    2nd part of a study to develop a taxonomy of value-in-use of library and information services based on users assessments and to propose methods and instruments for similar studies of library and information services in general
  3. Saracevic, T.: Information science (2009) 0.02
    0.017544128 = product of:
      0.07017651 = sum of:
        0.02834915 = weight(_text_:libraries in 3812) [ClassicSimilarity], result of:
          0.02834915 = score(doc=3812,freq=2.0), product of:
            0.13017908 = queryWeight, product of:
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.03962768 = queryNorm
            0.2177704 = fieldWeight in 3812, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.046875 = fieldNorm(doc=3812)
        0.04182736 = weight(_text_:studies in 3812) [ClassicSimilarity], result of:
          0.04182736 = score(doc=3812,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 3812, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=3812)
      0.25 = coord(2/8)
    
    Abstract
    The purpose of this entry is to provide an overview of information science as a field or discipline, including a historical perspective to illustrate the events and forces that shaped it. Information science is a field of professional practice and scientific inquiry dealing with effective communication of information and information objects, particularly knowledge records, among humans in the context of social, organizational, and individual need for and use of information. Information science emerged in the aftermath of the Second World War, as did a number of other fields, addressing the problem of information explosion and using technology as a solution. Presently, information science deals with the same problems in the Web and digital environments. This entry covers problems addressed by information science, the intellectual structure of the field, and the description of main areas-information retrieval, human information behavior, metric studies, and digital libraries. This entry also includes an account of education related to information science and conclusions about major characteristics.
  4. Mokros, H.B.; Mullins, L.S.; Saracevic, T.: Practice and personhood in professional interaction : social identities and information needs (1995) 0.01
    0.0073941024 = product of:
      0.05915282 = sum of:
        0.05915282 = weight(_text_:studies in 4080) [ClassicSimilarity], result of:
          0.05915282 = score(doc=4080,freq=4.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.37408823 = fieldWeight in 4080, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=4080)
      0.125 = coord(1/8)
    
    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
  5. Saracevic, T.: Individual differences in organizing, searching and retrieving information (1991) 0.01
    0.0069712265 = product of:
      0.055769812 = sum of:
        0.055769812 = weight(_text_:studies in 3692) [ClassicSimilarity], result of:
          0.055769812 = score(doc=3692,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.35269377 = fieldWeight in 3692, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.0625 = fieldNorm(doc=3692)
      0.125 = coord(1/8)
    
    Abstract
    Synthesises the major findings of several decades of research into the magnitude of individual deffirences in information retrieval related tasks and suggests implications for practice and design. The study is related to a series of studies of human aspects and cognitive decision making in information seeking, searching and retrieving
  6. Kantor, P.B.; Saracevic, T.: Quantitative study of the value of research libraries : a foundation for the evaluation of digital libraries (1999) 0.01
    0.0066031897 = product of:
      0.052825518 = sum of:
        0.052825518 = weight(_text_:libraries in 6711) [ClassicSimilarity], result of:
          0.052825518 = score(doc=6711,freq=10.0), product of:
            0.13017908 = queryWeight, product of:
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.03962768 = queryNorm
            0.40579116 = fieldWeight in 6711, product of:
              3.1622777 = tf(freq=10.0), with freq of:
                10.0 = termFreq=10.0
              3.2850544 = idf(docFreq=4499, maxDocs=44218)
              0.0390625 = fieldNorm(doc=6711)
      0.125 = coord(1/8)
    
    Abstract
    In anticipation of the explosive growth of digital libraries, a complex study was undertaken seeking to evaluate 21 diverse services at 5 major academic research libraries. This work stands as a model for evaluation of digital libraries, through its focus on both the costs of operations and the impacts of the services that those operations provide. The data have been analyzed using both statistical methods and methods of Data Envelopment Analysis. The results of the study, which are presented in detail, serve to demonstrate that a cross-functional approach to library services is feasible. They also highlight a new measure of impact, which is a weighted logarithmic combination of the amount of time that users spend interacting with the service, combined with a Likert-scale indication of the value of that service in relation to the time expended. The measure derived, incorporating simple information obtainable from the user, together with information which is readily available in server/client logs, provides an excellent foundation for transferring these measurement principles to the Digital Library environment
  7. Bellardo, T.; Saracevic, T.: Online searching and search output : relationships between overlap, relevance, recall and precision (1987) 0.01
    0.0063469075 = product of:
      0.05077526 = sum of:
        0.05077526 = weight(_text_:case in 4150) [ClassicSimilarity], result of:
          0.05077526 = score(doc=4150,freq=2.0), product of:
            0.1742197 = queryWeight, product of:
              4.3964143 = idf(docFreq=1480, maxDocs=44218)
              0.03962768 = queryNorm
            0.29144385 = fieldWeight in 4150, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.3964143 = idf(docFreq=1480, maxDocs=44218)
              0.046875 = fieldNorm(doc=4150)
      0.125 = coord(1/8)
    
    Abstract
    A recent study begun at Case Western Reserve University and continued at Rutgers University compared the transcripts of 200 DIALOG searches conducted by 36 experienced searchers on real questions submitted by academic and industrial researchers. Relevance judgements by the researchers were used to give recall and precision scores to each search result. Findings included: a low degree of overlap between searches on the same question in selection of search terms or items retrieved; the more often an item was retrieved by different searchers, the more likely it was to be judged relevant; recall and precision were not necessarly inversly related; there was a significant positive impact on recall/precision from using more cycles (a sequence from selecting terms to displaying results); serious uncorrectd errors were a major problem in poor searches and proper selection of terms a key to successful searches.
  8. Saracevic, T.; Mokros, H.; Su, L.: Nature of interaction between users and intermediaries in online searching : a qualitative analysis (1990) 0.01
    0.00522842 = product of:
      0.04182736 = sum of:
        0.04182736 = weight(_text_:studies in 4894) [ClassicSimilarity], result of:
          0.04182736 = score(doc=4894,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 4894, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=4894)
      0.125 = coord(1/8)
    
    Abstract
    Reports preliminary results from a study, conducted at Rutgers Univ., School of Communication, Information and Library Studies, to conduct observations and experiments under real-life conditions on the nature, effects and patterns in the discourse between users and intermediary searchers and in the related computer commands in the context of online searching and responses. The study involved videotaping interactions between users and intermediaries and recording the search logs for 40 questions. Users judged the relevance of output and completed a number of other measures. Data is analysed both quantitatively, using standard and innovative statistical techniques, and qualitatively, through a grounded theory approach using microanalytic and observational methods
  9. Spink, A.; Saracevic, T.: Dynamics of search term selection during mediated online searching (1993) 0.01
    0.00522842 = product of:
      0.04182736 = sum of:
        0.04182736 = weight(_text_:studies in 7968) [ClassicSimilarity], result of:
          0.04182736 = score(doc=7968,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 7968, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=7968)
      0.125 = coord(1/8)
    
    Abstract
    One in a series of studies on the selection of search terms during an online search involving users and intermediaries in real online interactive situations. Considers: during what stage of the search process were search terms from different sources selected?; how were the search terms selected at different stages of the search process connected with retrieval of relevant answers as judges by users?; and in what sequences were the search terms selected, in respect to their sources. Sequences of selected search terms were analyzed to describe the types and frequencies of changes that occur in such sequences. Results indicate that search term selection follows regular patterns in the dynamics of the search process. Discusses implications of findings
  10. Saracevic, T.: Ciencia da informacao, origem, evolucao e relacoes (1996) 0.01
    0.00522842 = product of:
      0.04182736 = sum of:
        0.04182736 = weight(_text_:studies in 811) [ClassicSimilarity], result of:
          0.04182736 = score(doc=811,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 811, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=811)
      0.125 = coord(1/8)
    
    Abstract
    Information science is best defined as a discipline in terms of the problems it addresses. Its origins date back to the scientific and technical revolution after the 2nd World War, and its development has been essentially characterised by interdisciplinarity. Librarianship, computer science, cognitive science and communication studies all share interests with infomation science, but with increasing emphasis on the information society and the information industry dictated by technological imparatives, information science is now at a critical point in its evolution. The problem it sets out to solve are not decreasing but changing, with the pressure to improve access to an ever increasing store of knowledge. The social need for information science is evident, whatever the name given to the knowledge and skills which it encompasses
  11. Saracevic, T.; Kantor, P.B.: Studying the value of library and information services : Part I: Establishing a theoretical framework (1997) 0.01
    0.00522842 = product of:
      0.04182736 = sum of:
        0.04182736 = weight(_text_:studies in 352) [ClassicSimilarity], result of:
          0.04182736 = score(doc=352,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 352, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=352)
      0.125 = coord(1/8)
    
    Footnote
    1st part of a study to develop a taxonomy of value-in-use of library and information services based on users assessments and to propose methods and instruments for similar studies of library and information services in general
  12. Saracevic, T.; Kantor, P.; Chamis, A.Y.: ¬A study of information seeking and retrieving : pt.1: Background and methodology (1988) 0.01
    0.00522842 = product of:
      0.04182736 = sum of:
        0.04182736 = weight(_text_:studies in 1963) [ClassicSimilarity], result of:
          0.04182736 = score(doc=1963,freq=2.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.26452032 = fieldWeight in 1963, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.046875 = fieldNorm(doc=1963)
      0.125 = coord(1/8)
    
    Abstract
    The objectives of the study were to conduct a series of observations and experiments under as real-life a situation as possible related to: (i) user context of questions in information retrieval; (ii) the structure and classification of questions; (iii) cognitive traits and decision making of searchers; and (iv) different searches of the same question. The study is presented in three parts: part 1 presents the background of the study and describes the models, measures, methods, procedures and statistical analyses used. Pt.2 is devoted to results related to users, questions, and effectiveness measures, and pt.3 to results related to searchers, searches, and overlap studies. A concluding summary of all results is presented in pt.3
  13. Spink, A.; Wolfram, D.; Jansen, B.J.; Saracevic, T.: Searching the Web : the public and their queries (2001) 0.00
    0.0049294014 = product of:
      0.03943521 = sum of:
        0.03943521 = weight(_text_:studies in 6980) [ClassicSimilarity], result of:
          0.03943521 = score(doc=6980,freq=4.0), product of:
            0.15812531 = queryWeight, product of:
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03962768 = queryNorm
            0.24939215 = fieldWeight in 6980, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.9902744 = idf(docFreq=2222, maxDocs=44218)
              0.03125 = fieldNorm(doc=6980)
      0.125 = coord(1/8)
    
    Abstract
    In previous articles, we reported the state of Web searching in 1997 (Jansen, Spink, & Saracevic, 2000) and in 1999 (Spink, Wolfram, Jansen, & Saracevic, 2001). Such snapshot studies and statistics on Web use appear regularly (OCLC, 1999), but provide little information about Web searching trends. In this article, we compare and contrast results from our two previous studies of Excite queries' data sets, each containing over 1 million queries submitted by over 200,000 Excite users collected on 16 September 1997 and 20 December 1999. We examine how public Web searching changing during that 2-year time period. As Table 1 shows, the overall structure of Web queries in some areas did not change, while in others we see change from 1997 to 1999. Our comparison shows how Web searching changed incrementally and also dramatically. We see some moves toward greater simplicity, including shorter queries (i.e., fewer terms) and shorter sessions (i.e., fewer queries per user), with little modification (addition or deletion) of terms in subsequent queries. The trend toward shorter queries suggests that Web information content should target specific terms in order to reach Web users. Another trend was to view fewer pages of results per query. Most Excite users examined only one page of results per query, since an Excite results page contains ten ranked Web sites. Were users satisfied with the results and did not need to view more pages? It appears that the public continues to have a low tolerance of wading through retrieved sites. This decline in interactivity levels is a disturbing finding for the future of Web searching. Queries that included Boolean operators were in the minority, but the percentage increased between the two time periods. Most Boolean use involved the AND operator with many mistakes. The use of relevance feedback almost doubled from 1997 to 1999, but overall use was still small. An unusually large number of terms were used with low frequency, such as personal names, spelling errors, non-English words, and Web-specific terms, such as URLs. Web query vocabulary contains more words than found in large English texts in general. The public language of Web queries has its own and unique characteristics. How did Web searching topics change from 1997 to 1999? We classified a random sample of 2,414 queries from 1997 and 2,539 queries from 1999 into 11 categories (Table 2). From 1997 to 1999, Web searching shifted from entertainment, recreation and sex, and pornography, preferences to e-commerce-related topics under commerce, travel, employment, and economy. This shift coincided with changes in information distribution on the publicly indexed Web.
  14. Saracevic, T.: On a method for studying the structure and nature of requests in information retrieval (1983) 0.00
    0.003355627 = product of:
      0.026845016 = sum of:
        0.026845016 = product of:
          0.05369003 = sum of:
            0.05369003 = weight(_text_:22 in 2417) [ClassicSimilarity], result of:
              0.05369003 = score(doc=2417,freq=2.0), product of:
                0.13876937 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.03962768 = queryNorm
                0.38690117 = fieldWeight in 2417, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.078125 = fieldNorm(doc=2417)
          0.5 = coord(1/2)
      0.125 = coord(1/8)
    
    Pages
    S.22-25