Search (18 results, page 1 of 1)

  • × author_ss:"Mayr, P."
  • × year_i:[2000 TO 2010}
  1. Lauser, B.; Johannsen, G.; Caracciolo, C.; Hage, W.R. van; Keizer, J.; Mayr, P.: Comparing human and automatic thesaurus mapping approaches in the agricultural domain (2008) 0.04 
    0.040847298 = product of:
  0.081694596 = sum of:
    0.01213797 = weight(_text_:information in 2627) [ClassicSimilarity], result of:
      0.01213797 = score(doc=2627,freq=4.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.13714671 = fieldWeight in 2627, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2627)
    0.06955662 = sum of:
      0.035403505 = weight(_text_:organization in 2627) [ClassicSimilarity], result of:
        0.035403505 = score(doc=2627,freq=2.0), product of:
          0.17974974 = queryWeight, product of:
            3.5653565 = idf(docFreq=3399, maxDocs=44218)
            0.050415643 = queryNorm
          0.19695997 = fieldWeight in 2627, product of:
            1.4142135 = tf(freq=2.0), with freq of:
              2.0 = termFreq=2.0
            3.5653565 = idf(docFreq=3399, maxDocs=44218)
            0.0390625 = fieldNorm(doc=2627)
      0.03415312 = weight(_text_:22 in 2627) [ClassicSimilarity], result of:
        0.03415312 = score(doc=2627,freq=2.0), product of:
          0.17654699 = queryWeight, product of:
            3.5018296 = idf(docFreq=3622, maxDocs=44218)
            0.050415643 = queryNorm
          0.19345059 = fieldWeight in 2627, product of:
            1.4142135 = tf(freq=2.0), with freq of:
              2.0 = termFreq=2.0
            3.5018296 = idf(docFreq=3622, maxDocs=44218)
            0.0390625 = fieldNorm(doc=2627)
  0.5 = coord(2/4)
    Abstract
    Knowledge organization systems (KOS), like thesauri and other controlled vocabularies, are used to provide subject access to information systems across the web. Due to the heterogeneity of these systems, mapping between vocabularies becomes crucial for retrieving relevant information. However, mapping thesauri is a laborious task, and thus big efforts are being made to automate the mapping process. This paper examines two mapping approaches involving the agricultural thesaurus AGROVOC, one machine-created and one human created. We are addressing the basic question "What are the pros and cons of human and automatic mapping and how can they complement each other?" By pointing out the difficulties in specific cases or groups of cases and grouping the sample into simple and difficult types of mappings, we show the limitations of current automatic methods and come up with some basic recommendations on what approach to use when.
    Source
    Metadata for semantic and social applications : proceedings of the International Conference on Dublin Core and Metadata Applications, Berlin, 22 - 26 September 2008, DC 2008: Berlin, Germany / ed. by Jane Greenberg and Wolfgang Klas
  2. Mayr, P.; Petras, V.; Walter, A.-K.: Results from a German terminology mapping effort : intra- and interdisciplinary cross-concordances between controlled vocabularies (2007) 0.01 
    0.014769909 = product of:
  0.029539818 = sum of:
    0.012015978 = weight(_text_:information in 542) [ClassicSimilarity], result of:
      0.012015978 = score(doc=542,freq=8.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.13576832 = fieldWeight in 542, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.02734375 = fieldNorm(doc=542)
    0.01752384 = product of:
      0.03504768 = sum of:
        0.03504768 = weight(_text_:organization in 542) [ClassicSimilarity], result of:
          0.03504768 = score(doc=542,freq=4.0), product of:
            0.17974974 = queryWeight, product of:
              3.5653565 = idf(docFreq=3399, maxDocs=44218)
              0.050415643 = queryNorm
            0.19498043 = fieldWeight in 542, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.5653565 = idf(docFreq=3399, maxDocs=44218)
              0.02734375 = fieldNorm(doc=542)
      0.5 = coord(1/2)
  0.5 = coord(2/4)
    Abstract
    In 2004, the German Federal Ministry for Education and Research funded a major terminology mapping initiative at the GESIS Social Science Information Centre in Bonn (GESIS-IZ), which will find its conclusion this year. The task of this terminology mapping initiative was to organize, create and manage 'crossconcordances' between major controlled vocabularies (thesauri, classification systems, subject heading lists) centred around the social sciences but quickly extending to other subject areas. Cross-concordances are intellectually (manually) created crosswalks that determine equivalence, hierarchy, and association relations between terms from two controlled vocabularies. Most vocabularies have been related bilaterally, that is, there is a cross-concordance relating terms from vocabulary A to vocabulary B as well as a cross-concordance relating terms from vocabulary B to vocabulary A (bilateral relations are not necessarily symmetrical). Till August 2007, 24 controlled vocabularies from 11 disciplines will be connected with vocabulary sizes ranging from 2,000 - 17,000 terms per vocabulary. To date more than 260,000 relations are generated. A database including all vocabularies and cross-concordances was built and a 'heterogeneity service' developed, a web service, which makes the cross-concordances available for other applications. Many cross-concordances are already implemented and utilized for the German Social Science Information Portal Sowiport (www.sowiport.de), which searches bibliographical and other information resources (incl. 13 databases with 10 different vocabularies and ca. 2.5 million references).
    In the final phase of the project, a major evaluation effort is under way to test and measure the effectiveness of the vocabulary mappings in an information system environment. Actual user queries are tested in a distributed search environment, where several bibliographic databases with different controlled vocabularies are searched at the same time. Three query variations are compared to each other: a free-text search without focusing on using the controlled vocabulary or terminology mapping; a controlled vocabulary search, where terms from one vocabulary (a 'home' vocabulary thought to be familiar to the user of a particular database) are used to search all databases; and finally, a search, where controlled vocabulary terms are translated into the terms of the respective controlled vocabulary of the database. For evaluation purposes, types of cross-concordances are distinguished between intradisciplinary vocabularies (vocabularies within the social sciences) and interdisciplinary vocabularies (social sciences to other disciplines as well as other combinations). Simultaneously, an extensive quantitative analysis is conducted aimed at finding patterns in terminology mappings that can explain trends in the effectiveness of terminology mappings, particularly looking at overlapping terms, types of determined relations (equivalence, hierarchy etc.), size of participating vocabularies, etc. This project is the largest terminology mapping effort in Germany. The number and variety of controlled vocabularies targeted provide an optimal basis for insights and further research opportunities. To our knowledge, terminology mapping efforts have rarely been evaluated with stringent qualitative and quantitative measures. This research should contribute in this area. For the NKOS workshop, we plan to present an overview of the project and participating vocabularies, an introduction to the heterogeneity service and its application as well as some of the results and findings of the evaluation, which will be concluded in August.
    Content
    Präsentation während der Veranstaltung "Networked Knowledge Organization Systems and Services: The 6th European Networked Knowledge Organization Systems (NKOS) Workshop, Workshop at the 11th ECDL Conference, Budapest, Hungary, September 21st 2007".
  3. Mayr, P.; Walter, A.-K.: Mapping Knowledge Organization Systems (2008) 0.01 
    0.010621051 = product of:
  0.042484205 = sum of:
    0.042484205 = product of:
      0.08496841 = sum of:
        0.08496841 = weight(_text_:organization in 1676) [ClassicSimilarity], result of:
          0.08496841 = score(doc=1676,freq=8.0), product of:
            0.17974974 = queryWeight, product of:
              3.5653565 = idf(docFreq=3399, maxDocs=44218)
              0.050415643 = queryNorm
            0.47270393 = fieldWeight in 1676, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              3.5653565 = idf(docFreq=3399, maxDocs=44218)
              0.046875 = fieldNorm(doc=1676)
      0.5 = coord(1/2)
  0.25 = coord(1/4)
    Abstract
    Die Vernetzung der Informationssysteme und Datenbanken aus dem wissenschaftlichen Fachinformationsbereich lässt bislang den Aspekt der Kompatibilität und Konkordanz zwischen kontrollierten Vokabularen (semantische Heterogenität) weitgehend unberücksichtigt. Gerade aber für den inhaltlichen Zugang sachlich heterogen erschlössener Bestände spielen für den Nutzer die semantischen Querverbindungen (Mappings /Crosskonkordanzen) zwischen den zugrunde liegenden Knowledge Organization Systems (KOS) der Datenbanken eine entscheidende Rolle. Der Beitrag stellt Einsatzmöglichkeiten und Beispiele von Crosskonkordanzen (CK) im Projekt "Kompetenznetzwerk Modellbildung und Heterogenitätsbehandlung" (KoMoHe) sowie das Netz der bis dato entstandenen Terminolögie-Überstiege vor. Die am IZ entstandenen CK sollen künftig über einen Terminolögie-Service als Web Service genutzt werden, dieser wird im Beitrag exemplarisch vorgestellt.
    Source
    Kompatibilität, Medien und Ethik in der Wissensorganisation - Compatibility, Media and Ethics in Knowledge Organization: Proceedings der 10. Tagung der Deutschen Sektion der Internationalen Gesellschaft für Wissensorganisation Wien, 3.-5. Juli 2006 - Proceedings of the 10th Conference of the German Section of the International Society of Knowledge Organization Vienna, 3-5 July 2006. Ed.: H.P. Ohly, S. Netscher u. K. Mitgutsch
  4. Daniel, F.; Maier, C.; Mayr, P.; Wirtz, H.-C.: ¬Die Kunden dort bedienen, wo sie sind : DigiAuskunft besteht Bewährungsprobe / Seit Anfang 2006 in Betrieb (2006) 0.01 
    0.0059767957 = product of:
  0.023907183 = sum of:
    0.023907183 = product of:
      0.047814365 = sum of:
        0.047814365 = weight(_text_:22 in 5991) [ClassicSimilarity], result of:
          0.047814365 = score(doc=5991,freq=2.0), product of:
            0.17654699 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.050415643 = queryNorm
            0.2708308 = fieldWeight in 5991, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0546875 = fieldNorm(doc=5991)
      0.5 = coord(1/2)
  0.25 = coord(1/4)
    Date
    8. 7.2006 21:06:22
  5. Mayr, P.; Petras, V.: Building a Terminology Network for Search : the KoMoHe project (2008) 0.01 
    0.0059767957 = product of:
  0.023907183 = sum of:
    0.023907183 = product of:
      0.047814365 = sum of:
        0.047814365 = weight(_text_:22 in 2618) [ClassicSimilarity], result of:
          0.047814365 = score(doc=2618,freq=2.0), product of:
            0.17654699 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.050415643 = queryNorm
            0.2708308 = fieldWeight in 2618, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0546875 = fieldNorm(doc=2618)
      0.5 = coord(1/2)
  0.25 = coord(1/4)
    Source
    Metadata for semantic and social applications : proceedings of the International Conference on Dublin Core and Metadata Applications, Berlin, 22 - 26 September 2008, DC 2008: Berlin, Germany / ed. by Jane Greenberg and Wolfgang Klas
  6. Mayr, P.; Umstätter, W.: ¬Eine bibliometrische Zeitschriftenanalyse mit Jol Scientrometrics und NfD bzw. IWP (2008) 0.01 
    0.0052030715 = product of:
  0.020812286 = sum of:
    0.020812286 = weight(_text_:information in 2302) [ClassicSimilarity], result of:
      0.020812286 = score(doc=2302,freq=6.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.23515764 = fieldWeight in 2302, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0546875 = fieldNorm(doc=2302)
  0.25 = coord(1/4)
    Abstract
    In der Studie sind 3.889 Datensätze analysiert worden, die im Zeitraum 1976-2004 in der Datenbank Library and Information Science Abstracts (LISA) im Forschungsbereich der Informetrie nachgewiesen sind und das Wachstum auf diesem Gebiet belegen. Die Studie zeigt anhand einer Bradford-Verteilung (power law) die Kernzeitschriften in diesem Feld und bestätigt auf der Basis dieses LISA-Datensatzes, dass die Gründung einer neuen Zeitschrift, "Journals of Informetrics" (JoI), 2007 etwa zur rechten Zeit erfolgte. Im Verhältnis dazu wird die Entwicklung der Zeitschrift Scientometrics betrachtet und auch die der "Nachrichten für Dokumentation" (NfD) bzw. "Information - Wissenschaft und Praxis" (IWP).
    Source
    Information - Wissenschaft und Praxis. 59(2008) H.6/7, S.353-360
  7. Mayr, P.: ¬Die virtuelle Steinsuppe : kooperatives Verwalten von elektronischen Ressourcen mit Digilink (2007) 0.00 
    0.004855188 = product of:
  0.019420752 = sum of:
    0.019420752 = weight(_text_:information in 567) [ClassicSimilarity], result of:
      0.019420752 = score(doc=567,freq=4.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.21943474 = fieldWeight in 567, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0625 = fieldNorm(doc=567)
  0.25 = coord(1/4)
    Source
    Wa(h)re Information: 29. Österreichischer Bibliothekartag Bregenz, 19.-23.9.2006. Hrsg.: Harald Weigel
    Theme
    Information Gateway
  8. Mayr, P.; Petras, V.: Cross-concordances : terminology mapping and its effectiveness for information retrieval (2008) 0.00 
    0.0044597755 = product of:
  0.017839102 = sum of:
    0.017839102 = weight(_text_:information in 2323) [ClassicSimilarity], result of:
      0.017839102 = score(doc=2323,freq=6.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.20156369 = fieldWeight in 2323, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.046875 = fieldNorm(doc=2323)
  0.25 = coord(1/4)
    Abstract
    The German Federal Ministry for Education and Research funded a major terminology mapping initiative, which found its conclusion in 2007. The task of this terminology mapping initiative was to organize, create and manage 'cross-concordances' between controlled vocabularies (thesauri, classification systems, subject heading lists) centred around the social sciences but quickly extending to other subject areas. 64 crosswalks with more than 500,000 relations were established. In the final phase of the project, a major evaluation effort to test and measure the effectiveness of the vocabulary mappings in an information system environment was conducted. The paper reports on the cross-concordance work and evaluation results.
    Content
    Beitrag während: World library and information congress: 74th IFLA general conference and council, 10-14 August 2008, Québec, Canada.
  9. Mayr, P.; Mutschke, P.; Petras, V.: Reducing semantic complexity in distributed digital libraries : Treatment of term vagueness and document re-ranking (2008) 0.00 
    0.0037164795 = product of:
  0.014865918 = sum of:
    0.014865918 = weight(_text_:information in 1909) [ClassicSimilarity], result of:
      0.014865918 = score(doc=1909,freq=6.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.16796975 = fieldWeight in 1909, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0390625 = fieldNorm(doc=1909)
  0.25 = coord(1/4)
    Abstract
    Purpose - The general science portal "vascoda" merges structured, high-quality information collections from more than 40 providers on the basis of search engine technology (FAST) and a concept which treats semantic heterogeneity between different controlled vocabularies. First experiences with the portal show some weaknesses of this approach which come out in most metadata-driven Digital Libraries (DLs) or subject specific portals. The purpose of the paper is to propose models to reduce the semantic complexity in heterogeneous DLs. The aim is to introduce value-added services (treatment of term vagueness and document re-ranking) that gain a certain quality in DLs if they are combined with heterogeneity components established in the project "Competence Center Modeling and Treatment of Semantic Heterogeneity". Design/methodology/approach - Two methods, which are derived from scientometrics and network analysis, will be implemented with the objective to re-rank result sets by the following structural properties: the ranking of the results by core journals (so-called Bradfordizing) and ranking by centrality of authors in co-authorship networks. Findings - The methods, which will be implemented, focus on the query and on the result side of a search and are designed to positively influence each other. Conceptually, they will improve the search quality and guarantee that the most relevant documents in result sets will be ranked higher. Originality/value - The central impact of the paper focuses on the integration of three structural value-adding methods, which aim at reducing the semantic complexity represented in distributed DLs at several stages in the information retrieval process: query construction, search and ranking and re-ranking.
    Theme
    Information Gateway
  10. Mayr, P.: DigiLink - Die dritte Generation der Linklisten (2005) 0.00 
    0.0034331365 = product of:
  0.013732546 = sum of:
    0.013732546 = weight(_text_:information in 3582) [ClassicSimilarity], result of:
      0.013732546 = score(doc=3582,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.1551638 = fieldWeight in 3582, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0625 = fieldNorm(doc=3582)
  0.25 = coord(1/4)
    Theme
    Information Gateway
  11. Mayr, P.; Walter, A.-K.: Einsatzmöglichkeiten von Crosskonkordanzen (2007) 0.00 
    0.0034331365 = product of:
  0.013732546 = sum of:
    0.013732546 = weight(_text_:information in 162) [ClassicSimilarity], result of:
      0.013732546 = score(doc=162,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.1551638 = fieldWeight in 162, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0625 = fieldNorm(doc=162)
  0.25 = coord(1/4)
    Source
    http://www.gesis.org/Information/Forschungsuebersichten/Tagungsberichte/Vernetzung/Mayr-Walter.pdf
  12. Mayr, P.; Tosques, F.: Webometrische Analysen mit Hilfe der Google Web APIs (2005) 0.00 
    0.0030039945 = product of:
  0.012015978 = sum of:
    0.012015978 = weight(_text_:information in 3189) [ClassicSimilarity], result of:
      0.012015978 = score(doc=3189,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.13576832 = fieldWeight in 3189, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0546875 = fieldNorm(doc=3189)
  0.25 = coord(1/4)
    Source
    Information - Wissenschaft und Praxis. 56(2005) H.1, S.41-48
  13. Krause, J.; Mayr, P.: Allgemeiner Bibliothekszugang und Varianten der Suchtypologie : Konsequenzen für die Modellbildung in vascoda (2007) 0.00 
    0.0030039945 = product of:
  0.012015978 = sum of:
    0.012015978 = weight(_text_:information in 5998) [ClassicSimilarity], result of:
      0.012015978 = score(doc=5998,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.13576832 = fieldWeight in 5998, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0546875 = fieldNorm(doc=5998)
  0.25 = coord(1/4)
    Theme
    Information Gateway
  14. Mayr, P.: Google Scholar als akademische Suchmaschine (2009) 0.00 
    0.0029731835 = product of:
  0.011892734 = sum of:
    0.011892734 = weight(_text_:information in 3023) [ClassicSimilarity], result of:
      0.011892734 = score(doc=3023,freq=6.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.1343758 = fieldWeight in 3023, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.03125 = fieldNorm(doc=3023)
  0.25 = coord(1/4)
    Abstract
    Neben den klassischen Informationsanbietern Bibliothek, Fachinformation und den Verlagen sind Internetsuchmaschinen inzwischen fester Bestandteil bei der Recherche nach wissenschaftlicher Information. Scirus (Elsevier, 2004) und Google Scholar sind zwei Beispiele für Suchdienste kommerzieller Suchmaschinen-Unternehmen, die eine Einschränkung auf den wissenschaftlichen Dokumentenraum anstreben und nennenswerte Dokumentzahlen in allen Disziplinen generieren. Der Vergleich der Treffermengen für beliebige Suchthemen zeigt, dass die Wahl des Suchsystems, des Dokumentenpools und der Dokumenttypen entscheidenden Einfluss auf die Relevanz und damit letztlich auch die Akzeptanz des Suchergebnisses hat. Tabelle 1 verdeutlicht die Mengenunterschiede am Beispiel der Trefferergebnisse für die Suchbegriffe "search engines" bzw. "Suchmaschinen" in der allgemeinen Internetsuchmaschine Google, der wissenschaftlichen Suchmaschine Google Scholar (GS) und der größten fachübergreifenden bibliographischen Literaturdatenbank Web of Science (WoS). Der Anteil der Dokumente, die in diesem Fall eindeutig der Wissenschaft zuzuordnen sind (siehe GS und insbesondere WoS in Tabelle 1), liegt gegenüber der allgemeinen Websuche lediglich im Promille-Bereich. Dieses Beispiel veranschaulicht, dass es ausgesprochen problematisch sein kann, fachwissenschaftliche Fragestellungen ausschließlich mit Internetsuchmaschinen zu recherchieren. Der Anteil der fachwissenschaftlich relevanten Dokumente in diesem Trefferpool ist i. d. R. sehr gering. Damit sinkt die Wahrscheinlichkeit, wissenschaftlich relevantes (z. B. einen Zeitschriftenaufsatz) auf den ersten Trefferseiten zu finden, deutlich ab.
    Die drei oben genannten Suchsysteme (Google, GS und WoS) unterscheiden sich in mehrerlei Hinsicht fundamental und eignen sich daher gut, um in die Grundthematik dieses Artikels einzuleiten. Die obigen Suchsysteme erschließen zunächst unterschiedliche Suchräume, und dies auf sehr spezifische Weise. Während Google frei zugängliche und über Hyperlink adressierbare Dokumente im Internet erfasst, gehen die beiden akademischen Suchsysteme deutlich selektiver bei der Inhaltserschließung vor. Google Scholar erfasst neben frei zugänglichen elektronischen Publikationstypen im Internet hauptsächlich wissenschaftliche Dokumente, die direkt von den akademischen Verlagen bezogen werden. Das WoS, das auf den unterschiedlichen bibliographischen Datenbanken und Zitationsindizes des ehemaligen "Institute for Scientific Information" (ISI) basiert, selektiert gegenüber den rein automatischen brute-force-Ansätzen der Internetsuchmaschine über einen qualitativen Ansatz. In den Datenbanken des WoS werden ausschließlich internationale Fachzeitschriften erfasst, die ein kontrolliertes Peer-Review durchlaufen. Insgesamt werden ca. 12.000 Zeitschriften ausgewertet und über die Datenbank verfügbar gemacht. Wie bereits erwähnt, spielt neben der Abgrenzung der Suchräume und Dokumenttypen die Zugänglichkeit und Relevanz der Dokumente eine entscheidende Bedeutung für den Benutzer. Die neueren technologischen Entwicklungen des Web Information Retrieval (IR), wie sie Google oder GS implementieren, werten insbesondere frei zugängliche Dokumente mit ihrer gesamten Text- und Linkinformation automatisch aus. Diese Verfahren sind vor allem deshalb erfolgreich, weil sie Ergebnislisten nach Relevanz gerankt darstellen, einfach und schnell zu recherchieren sind und direkt auf die Volltexte verweisen. Die qualitativen Verfahren der traditionellen Informationsanbieter (z. B. WoS) hingegen zeigen genau bei diesen Punkten (Ranking, Einfachheit und Volltextzugriff) Schwächen, überzeugen aber vor allem durch ihre Stringenz, in diesem Fall die selektive Aufnahme von qualitätsgeprüften Dokumenten in das System und die inhaltliche Erschließung der Dokumente (siehe dazu Mayr und Petras, 2008).
  15. Mayr, P.; Walter, A.-K.: Abdeckung und Aktualität des Suchdienstes Google Scholar (2006) 0.00 
    0.0025748524 = product of:
  0.01029941 = sum of:
    0.01029941 = weight(_text_:information in 5131) [ClassicSimilarity], result of:
      0.01029941 = score(doc=5131,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.116372846 = fieldWeight in 5131, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.046875 = fieldNorm(doc=5131)
  0.25 = coord(1/4)
    Source
    Information - Wissenschaft und Praxis. 57(2006) H.3, S.133-140
  16. Mayr, P.: Informationsangebote für das Wissenschaftsportal vascoda : eine Bestandsaufnahme (2006) 0.00 
    0.0025748524 = product of:
  0.01029941 = sum of:
    0.01029941 = weight(_text_:information in 154) [ClassicSimilarity], result of:
      0.01029941 = score(doc=154,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.116372846 = fieldWeight in 154, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.046875 = fieldNorm(doc=154)
  0.25 = coord(1/4)
    Theme
    Information Gateway
  17. Lewandowski, D.; Mayr, P.: Exploring the academic invisible Web (2006) 0.00 
    0.0021457102 = product of:
  0.008582841 = sum of:
    0.008582841 = weight(_text_:information in 3752) [ClassicSimilarity], result of:
      0.008582841 = score(doc=3752,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.09697737 = fieldWeight in 3752, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0390625 = fieldNorm(doc=3752)
  0.25 = coord(1/4)
    Abstract
    Purpose: To provide a critical review of Bergman's 2001 study on the Deep Web. In addition, we bring a new concept into the discussion, the Academic Invisible Web (AIW). We define the Academic Invisible Web as consisting of all databases and collections relevant to academia but not searchable by the general-purpose internet search engines. Indexing this part of the Invisible Web is central to scien-tific search engines. We provide an overview of approaches followed thus far. Design/methodology/approach: Discussion of measures and calculations, estima-tion based on informetric laws. Literature review on approaches for uncovering information from the Invisible Web. Findings: Bergman's size estimate of the Invisible Web is highly questionable. We demonstrate some major errors in the conceptual design of the Bergman paper. A new (raw) size estimate is given. Research limitations/implications: The precision of our estimate is limited due to a small sample size and lack of reliable data. Practical implications: We can show that no single library alone will be able to index the Academic Invisible Web. We suggest collaboration to accomplish this task. Originality/value: Provides library managers and those interested in developing academic search engines with data on the size and attributes of the Academic In-visible Web.
  18. Lewandowski, D.; Mayr, P.: Exploring the academic invisible Web (2006) 0.00 
    0.0021457102 = product of:
  0.008582841 = sum of:
    0.008582841 = weight(_text_:information in 2580) [ClassicSimilarity], result of:
      0.008582841 = score(doc=2580,freq=2.0), product of:
        0.08850355 = queryWeight, product of:
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.050415643 = queryNorm
        0.09697737 = fieldWeight in 2580, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.7554779 = idf(docFreq=20772, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2580)
  0.25 = coord(1/4)
    Abstract
    Purpose: To provide a critical review of Bergman's 2001 study on the deep web. In addition, we bring a new concept into the discussion, the academic invisible web (AIW). We define the academic invisible web as consisting of all databases and collections relevant to academia but not searchable by the general-purpose internet search engines. Indexing this part of the invisible web is central to scientific search engines. We provide an overview of approaches followed thus far. Design/methodology/approach: Discussion of measures and calculations, estimation based on informetric laws. Literature review on approaches for uncovering information from the invisible web. Findings: Bergman's size estimate of the invisible web is highly questionable. We demonstrate some major errors in the conceptual design of the Bergman paper. A new (raw) size estimate is given. Research limitations/implications: The precision of our estimate is limited due to a small sample size and lack of reliable data. Practical implications: We can show that no single library alone will be able to index the academic invisible web. We suggest collaboration to accomplish this task. Originality/value: Provides library managers and those interested in developing academic search engines with data on the size and attributes of the academic invisible web.

Authors

Languages

  • d 10
  • e 7

Types

Themes