Search (9 results, page 1 of 1)

  • × theme_ss:"Konzeption und Anwendung des Prinzips Thesaurus"
  • × theme_ss:"Semantisches Umfeld in Indexierung u. Retrieval"
  • × type_ss:"a"
  1. Chen, H.; Martinez, J.; Kirchhoff, A.; Ng, T.D.; Schatz, B.R.: Alleviating search uncertainty through concept associations : automatic indexing, co-occurence analysis, and parallel computing (1998) 0.00
    0.0024857575 = product of:
      0.004971515 = sum of:
        0.004971515 = product of:
          0.00994303 = sum of:
            0.00994303 = weight(_text_:a in 5202) [ClassicSimilarity], result of:
              0.00994303 = score(doc=5202,freq=12.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.18723148 = fieldWeight in 5202, product of:
                  3.4641016 = tf(freq=12.0), with freq of:
                    12.0 = termFreq=12.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=5202)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    In this article, we report research on an algorithmic approach to alleviating search uncertainty in a large information space. Grounded on object filtering, automatic indexing, and co-occurence analysis, we performed a large-scale experiment using a parallel supercomputer (SGI Power Challenge) to analyze 400.000+ abstracts in an INSPEC computer engineering collection. Two system-generated thesauri, one based on a combined object filtering and automatic indexing method, and the other based on automatic indexing only, were compaed with the human-generated INSPEC subject thesaurus. Our user evaluation revealed that the system-generated thesauri were better than the INSPEC thesaurus in 'concept recall', but in 'concept precision' the 3 thesauri were comparable. Our analysis also revealed that the terms suggested by the 3 thesauri were complementary and could be used to significantly increase 'variety' in search terms the thereby reduce search uncertainty
    Type
    a
  2. Shiri, A.A.; Revie, C.; Chowdhury, G.: Thesaurus-assisted search term selection and query expansion : a review of user-centred studies (2002) 0.00
    0.0024857575 = product of:
      0.004971515 = sum of:
        0.004971515 = product of:
          0.00994303 = sum of:
            0.00994303 = weight(_text_:a in 1330) [ClassicSimilarity], result of:
              0.00994303 = score(doc=1330,freq=12.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.18723148 = fieldWeight in 1330, product of:
                  3.4641016 = tf(freq=12.0), with freq of:
                    12.0 = termFreq=12.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=1330)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    This paper provides a review of the literature related to the application of domain-specific thesauri in the search and retrieval process. Focusing an studies that adopt a user-centred approach, the review presents a survey of the methodologies and results from empirical studies undertaken an the use of thesauri as sources of term selection for query formulation and expansion during the search process. It summarises the ways in which domain-specific thesauri from different disciplines have been used by various types of users and how these tools aid users in the selection of search terms. The review consists of two main sections: first, studies an thesaurus-aided search term selection; and second, studies dealing with query expansion using thesauri. Both sections are illustrated with case studies that have adopted a user-centred approach.
    Type
    a
  3. Spiteri, L.F.: ¬The essential elements of faceted thesauri (1999) 0.00
    0.0024857575 = product of:
      0.004971515 = sum of:
        0.004971515 = product of:
          0.00994303 = sum of:
            0.00994303 = weight(_text_:a in 5362) [ClassicSimilarity], result of:
              0.00994303 = score(doc=5362,freq=12.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.18723148 = fieldWeight in 5362, product of:
                  3.4641016 = tf(freq=12.0), with freq of:
                    12.0 = termFreq=12.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=5362)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    The goal of this study is to evaluate, compare, and contrast how facet analysis is used to construct the systematic or faceted displays of a selection of information retrieval thesauri. More specifically, the study seeks to examine which principles of facet analysis are used in the thesauri, and the extent to which different thesauri apply these principles in the same way. A measuring instrument was designed for the purpose of evaluating the structure of faceted thesauri. This instrument was applied to fourteen faceted information retrieval thesauri. The study reveals that the thesauri do not share a common definition of what constitutes a facet. In some cases, the thesauri apply both enumerative-style classification and facet analysis to arrange their indexing terms. A number of the facets used in the thesauri are not homogeneous or mutually exclusive. The principle of synthesis is used in only 50% of the thesauri, and no one citation order is used consistently by the thesauri.
    Type
    a
  4. Shapiro, C.D.; Yan, P.-F.: Generous tools : thesauri in digital libraries (1996) 0.00
    0.0023678814 = product of:
      0.0047357627 = sum of:
        0.0047357627 = product of:
          0.009471525 = sum of:
            0.009471525 = weight(_text_:a in 3132) [ClassicSimilarity], result of:
              0.009471525 = score(doc=3132,freq=8.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.17835285 = fieldWeight in 3132, product of:
                  2.828427 = tf(freq=8.0), with freq of:
                    8.0 = termFreq=8.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=3132)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    The Electronic Libraries and Information Highways MITRE Sponsored Research project aims to help searchers working in digital libraries increase their chance of matching the language of authors. Focuses on whether query formulation can be improved through the addition of semantic knowledge that is interactively gathered from a thesaurus that exists in a distributed, interoperating, cooperative environment. A prototype, ELVIS, was built that improves information retrieval through query expansion and is based on publicly available Z39.50 standard thesauri integrated with networked information discovery and retrieval tools
    Type
    a
  5. Sihvonen, A.; Vakkari, P.: Subject knowledge improves interactive query expansion assisted by a thesaurus (2004) 0.00
    0.0022374375 = product of:
      0.004474875 = sum of:
        0.004474875 = product of:
          0.00894975 = sum of:
            0.00894975 = weight(_text_:a in 4417) [ClassicSimilarity], result of:
              0.00894975 = score(doc=4417,freq=14.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.1685276 = fieldWeight in 4417, product of:
                  3.7416575 = tf(freq=14.0), with freq of:
                    14.0 = termFreq=14.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=4417)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    This study explores how experts and novices in pedagogics expanded queries supported by the ERIC thesaurus, and how this was connected to the search effectiveness in an easy and a difficult search task. The expert group consisted of 15 undergraduates in pedagogy and the novice group of 15 students with no previous studies in this field. Their search logs were recorded and a pre- and post-search interview was conducted. The results show that the number and type of terms selected from the thesaurus for expansion by experts improved search effectiveness, whereas there were no connections between the use of thesaurus and improvement of effectiveness among novices. The effectiveness of expansions varied between the facets of the queries. Thus, a vital condition for benefiting from a thesaurus in query expansion to improve search results is sufficient familiarity with the search topic. The results suggest also that it is not in the first place the number of terms used in expansion, but their type and quality that are crucial for search success.
    Type
    a
  6. Tudhope, D.; Alani, H.; Jones, C.: Augmenting thesaurus relationships : possibilities for retrieval (2001) 0.00
    0.0020714647 = product of:
      0.0041429293 = sum of:
        0.0041429293 = product of:
          0.008285859 = sum of:
            0.008285859 = weight(_text_:a in 1520) [ClassicSimilarity], result of:
              0.008285859 = score(doc=1520,freq=12.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.15602624 = fieldWeight in 1520, product of:
                  3.4641016 = tf(freq=12.0), with freq of:
                    12.0 = termFreq=12.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=1520)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    This paper discusses issues concerning the augmentation of thesaurus relationships, in light of new application possibilities for retrieval. We first discuss a case study that explored the retrieval potential of an augmented set of thesaurus relationships by specialising standard relationships into richer subtypes, in particular hierarchical geographical containment and the associative relationship. We then locate this work in a broader context by reviewing various attempts to build taxonomies of thesaurus relationships, and conclude by discussing the feasibility of hierarchically augmenting the core set of thesaurus relationships, particularly the associative relationship. We discuss the possibility of enriching the specification and semantics of Related Term (RT relationships), while maintaining compatibility with traditional thesauri via a limited hierarchical extension of the associative (and hierarchical) relationships. This would be facilitated by distinguishing the type of term from the (sub)type of relationship and explicitly specifying semantic categories for terms following a faceted approach. We first illustrate how hierarchical spatial relationships can be used to provide more flexible retrieval for queries incorporating place names in applications employing online gazetteers and geographical thesauri. We then employ a set of experimental scenarios to investigate key issues affecting use of the associative (RT) thesaurus relationships in semantic distance measures. Previous work has noted the potential of RTs in thesaurus search aids but also the problem of uncontrolled expansion of query term sets. Results presented in this paper suggest the potential for taking account of the hierarchical context of an RT link and specialisations of the RT relationship
    Type
    a
  7. Shiri, A.A.; Revie, C.; Chowdhury, G.: Thesaurus-enhanced search interfaces (2002) 0.00
    0.0020296127 = product of:
      0.0040592253 = sum of:
        0.0040592253 = product of:
          0.008118451 = sum of:
            0.008118451 = weight(_text_:a in 3807) [ClassicSimilarity], result of:
              0.008118451 = score(doc=3807,freq=2.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.15287387 = fieldWeight in 3807, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.09375 = fieldNorm(doc=3807)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Type
    a
  8. Shiri, A.: Topic familiarity and its effects on term selection and browsing in a thesaurus-enhanced search environment (2005) 0.00
    0.0016913437 = product of:
      0.0033826875 = sum of:
        0.0033826875 = product of:
          0.006765375 = sum of:
            0.006765375 = weight(_text_:a in 613) [ClassicSimilarity], result of:
              0.006765375 = score(doc=613,freq=8.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.12739488 = fieldWeight in 613, product of:
                  2.828427 = tf(freq=8.0), with freq of:
                    8.0 = termFreq=8.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=613)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    Purpose - To evaluate the extent to which familiarity with search topics affects the ways in which users select and browse search terms in a thesaurus-enhanced search setting. Design/methodology/approach - An experimental methodology was adopted to study users' search behaviour in an operational information retrieval environment. Findings - Topic familiarity and subject knowledge influence some search and interaction behaviours. Searches involving moderately and very familiar topics were associated with browsing around twice as many thesaurus terms as was the case for unfamiliar topics. Research limitations/implications - Some search behaviours such as thesaurus browsing and term selection could be used as an indication of user levels of topic familiarity. Practical implications - The results of this study provide design implications as to how to develop personalized search interfaces where users with varying levels of familiarity with search topics can carry out searches. Originality/value - This paper establishes the importance of topic familiarity characteristics and the effects of those characteristics on users' interaction with search interfaces enhanced with semantic tools such as thesauri.
    Type
    a
  9. Shiri, A.A.; Revie, C.: End-user interaction with thesauri : an evaluation of cognitive overlap in search term selection (2004) 0.00
    0.0014351527 = product of:
      0.0028703054 = sum of:
        0.0028703054 = product of:
          0.005740611 = sum of:
            0.005740611 = weight(_text_:a in 2658) [ClassicSimilarity], result of:
              0.005740611 = score(doc=2658,freq=4.0), product of:
                0.053105544 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046056706 = queryNorm
                0.10809815 = fieldWeight in 2658, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2658)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    The use of thesaurus-enhanced search tools is an the increase. This paper provides an insight into end-users interaction with and perceptions of such tools. In particular the overlap between users' initial query formulation and thesaurus structures is investigated. This investigation involved the performance of genuine search tasks an the CAB Abstracts database by academic users in the domain of veterinary medicine. The perception of these users regarding the nature and usefulness of the terms suggested from the thesaurus during the search interaction is reported. The results indicated that around 80% of terms entered were matched either exactly or partially to thesaurus terms. Users found over 90% of the terms suggested to be close to their search topics and where terms were selected they indicated that around 50% were to support a 'narrowing down' activity. These findings have implications for the design of thesaurus-enhanced interfaces.
    Type
    a