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  • × author_ss:"Mayr, P."
  1. Mayr, P.; Schaer, P.; Mutschke, P.: ¬A science model driven retrieval prototype (2011) 0.01
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    Abstract
    This paper is about a better understanding of the structure and dynamics of science and the usage of these insights for compensating the typical problems that arises in metadata-driven Digital Libraries. Three science model driven retrieval services are presented: co-word analysis based query expansion, re-ranking via Bradfordizing and author centrality. The services are evaluated with relevance assessments from which two important implications emerge: (1) precision values of the retrieval services are the same or better than the tf-idf retrieval baseline and (2) each service retrieved a disjoint set of documents. The different services each favor quite other - but still relevant - documents than pure term-frequency based rankings. The proposed models and derived retrieval services therefore open up new viewpoints on the scientific knowledge space and provide an alternative framework to structure scholarly information systems.
    Source
    Concepts in context: Proceedings of the Cologne Conference on Interoperability and Semantics in Knowledge Organization July 19th - 20th, 2010. Eds.: F. Boteram, W. Gödert u. J. Hubrich
    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  2. Mayr, P.; Petras, V.: Cross-concordances : terminology mapping and its effectiveness for information retrieval (2008) 0.01
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    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.
    Date
    26.12.2011 13:33:29
  3. Mayr, P.; Mutschke, P.; Petras, V.; Schaer, P.; Sure, Y.: Applying science models for search (2010) 0.01
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    Abstract
    The paper proposes three different kinds of science models as value-added services that are integrated in the retrieval process to enhance retrieval quailty. The paper discusses the approaches Search Term Recommendation, Bradfordizing and Author Centrality on a general level and addresses implementation issues of the models within a real-life retrieval environment.
  4. 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) 0.01
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    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
  5. Daquino, M.; Peroni, S.; Shotton, D.; Colavizza, G.; Ghavimi, B.; Lauscher, A.; Mayr, P.; Romanello, M.; Zumstein, P.: ¬The OpenCitations Data Model (2020) 0.01
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    Abstract
    A variety of schemas and ontologies are currently used for the machine-readable description of bibliographic entities and citations. This diversity, and the reuse of the same ontology terms with different nuances, generates inconsistencies in data. Adoption of a single data model would facilitate data integration tasks regardless of the data supplier or context application. In this paper we present the OpenCitations Data Model (OCDM), a generic data model for describing bibliographic entities and citations, developed using Semantic Web technologies. We also evaluate the effective reusability of OCDM according to ontology evaluation practices, mention existing users of OCDM, and discuss the use and impact of OCDM in the wider open science community.
  6. Mayr, P.; Mutschke, P.; Petras, V.: Reducing semantic complexity in distributed digital libraries : Treatment of term vagueness and document re-ranking (2008) 0.01
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    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.
  7. Mayr, P.; Scharnhorst, A.: Scientometrics and information retrieval - weak-links revitalized (2015) 0.01
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    Footnote
    Editorial zu einem Special Issue "Combining bibliometrics and information retrieval"
  8. Mayr, P.: Thesauri, Klassifikationen & Co - die Renaissance der kontrollierten Vokabulare? (2006) 0.01
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    Abstract
    Der Beitrag beschäftigt sich mit aktuellen Entwicklungen im Bereich des Terminologie Mapping zwischen kontrollierten Vokabularen. Die unterschiedlichen Typen und Ausprägungen von kontrollierten Vokabularen - Thesauri, Klassifikationen, Schlagwortnormdaten und kontrollierte Schlagwortlisten - dienen hauptsächlich der inhaltlichen Erschließung von Literatur und anderen Dokumenttypen und werden u. a. in Datenbanksystemen bei der Deskriptorensuche und zum Browsing angeboten. Die Zusammenführung der heterogenen Indexierungssprachen bei der übergreifenden Datenbankrecherche (crossdatabase retrieval) führt jedoch zu Problemen bei der semantischen Integration der zugrunde liegenden Bestände. Der Beitrag stellt in diesem Kontext den Ansatz sowie die bisherigen Ergebnisse des Projekts" Modellbildung und Heterogenitätsbehandlung" vor. Im Anschluss wird auf Bradford's Law of Scattering (BLS) sowie abgeleitete Einsatzmöglichkeiten des BLS im Projekt Bezug genommen: 1) BLS zur Untersuchung der Auswirkungen der Heterogenitätsbehandlung, 2) BLS bzw. Bradfordizing als alternativer, informationswissenschaftlich begründeter Zugangsmechanismus für Zeitschriftenartikel.
  9. Mutschke, P.; Mayr, P.: Science models for search : a study on combining scholarly information retrieval and scientometrics (2015) 0.01
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    Footnote
    Beitrag in einem Special Issue "Combining bibliometrics and information retrieval"
  10. Mayr, P.; Petras, V.: Building a Terminology Network for Search : the KoMoHe project (2008) 0.01
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    Abstract
    The paper reports about results on the GESIS-IZ project "Competence Center Modeling and Treatment of Semantic Heterogeneity" (KoMoHe). KoMoHe supervised a terminology mapping effort, in which 'cross-concordances' between major controlled vocabularies were organized, created and managed. In this paper we describe the establishment and implementation of crossconcordances for search in a digital library (DL).
    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
  11. Mayr, P.: Information Retrieval-Mehrwertdienste für Digitale Bibliotheken: : Crosskonkordanzen und Bradfordizing (2010) 0.00
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    RSWK
    Dokumentationssprache / Heterogenität / Information Retrieval / Ranking / Evaluation
    Subject
    Dokumentationssprache / Heterogenität / Information Retrieval / Ranking / Evaluation
  12. Mayr, P.: Google Scholar als akademische Suchmaschine (2009) 0.00
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    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).
  13. Mayr, P.; Mutschke, P.; Schaer, P.; Sure, Y.: Mehrwertdienste für das Information Retrieval (2013) 0.00
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    Abstract
    Ziel des Projekts ist die Entwicklung und Erprobung von metadatenbasierten Mehr-wertdiensten für Retrievalumgebungen mit mehreren Datenbanken: a) Search Term Recommender (STR) als Dienst zum automatischen Vorschlagen von Suchbegriffen aus kontrollierten Vokabularen, b) Bradfordizing als Dienst zum Re-Ranking von Ergebnismengen nach Kernzeitschriften und c) Autorenzentralität als Dienst zum Re-Ranking von. Ergebnismengen nach Zentralität der Autoren in Autorennetzwerken. Schwerpunkt des Projektes ist die prototypische mplementierung der drei Mehrwertdienste in einer integrierten Retrieval-Testumgebung und insbesondere deren quantitative und qualitative Evaluation hinsichtlich Verbesserung der Retrievalqualität bei Einsatz der Mehrwertdienste.
  14. Mayr, P.: Bradfordizing als Re-Ranking-Ansatz in Literaturinformationssystemen (2011) 0.00
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    Abstract
    In diesem Artikel wird ein Re-Ranking-Ansatz für Suchsysteme vorgestellt, der die Recherche nach wissenschaftlicher Literatur messbar verbessern kann. Das nichttextorientierte Rankingverfahren Bradfordizing wird eingeführt und anschließend im empirischen Teil des Artikels bzgl. der Effektivität für typische fachbezogene Recherche-Topics evaluiert. Dem Bradford Law of Scattering (BLS), auf dem Bradfordizing basiert, liegt zugrunde, dass sich die Literatur zu einem beliebigen Fachgebiet bzw. -thema in Zonen unterschiedlicher Dokumentenkonzentration verteilt. Dem Kernbereich mit hoher Konzentration der Literatur folgen Bereiche mit mittlerer und geringer Konzentration. Bradfordizing sortiert bzw. rankt eine Dokumentmenge damit nach den sogenannten Kernzeitschriften. Der Retrievaltest mit 164 intellektuell bewerteten Fragestellungen in Fachdatenbanken aus den Bereichen Sozial- und Politikwissenschaften, Wirtschaftswissenschaften, Psychologie und Medizin zeigt, dass die Dokumente der Kernzeitschriften signifikant häufiger relevant bewertet werden als Dokumente der zweiten Dokumentzone bzw. den Peripherie-Zeitschriften. Die Implementierung von Bradfordizing und weiteren Re-Rankingverfahren liefert unmittelbare Mehrwerte für den Nutzer.
    Date
    9. 2.2011 17:47:29
  15. Mayr, P.; Petras, V.: Crosskonkordanzen : Terminologie Mapping und deren Effektivität für das Information Retrieval 0.00
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  16. Hobert, A.; Jahn, N.; Mayr, P.; Schmidt, B.; Taubert, N.: Open access uptake in Germany 2010-2018 : adoption in a diverse research landscape (2021) 0.00
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    Abstract
    Es handelt sich um eine bibliometrische Untersuchung der Entwicklung der Open-Access-Verfügbarkeit wissenschaftlicher Zeitschriftenartikel in Deutschland, die im Zeitraum 2010-18 erschienen und im Web of Science indexiert sind. Ein besonderes Augenmerk der Analyse lag auf der Frage, ob und inwiefern sich die Open-Access-Profile der Universitäten und außeruniversitären Wissenschaftseinrichtungen in Deutschland voneinander unterscheiden.
    Content
    This study investigates the development of open access (OA) to journal articles from authors affiliated with German universities and non-university research institutions in the period 2010-2018. Beyond determining the overall share of openly available articles, a systematic classification of distinct categories of OA publishing allowed us to identify different patterns of adoption of OA. Taking into account the particularities of the German research landscape, variations in terms of productivity, OA uptake and approaches to OA are examined at the meso-level and possible explanations are discussed. The development of the OA uptake is analysed for the different research sectors in Germany (universities, non-university research institutes of the Helmholtz Association, Fraunhofer Society, Max Planck Society, Leibniz Association, and government research agencies). Combining several data sources (incl. Web of Science, Unpaywall, an authority file of standardised German affiliation information, the ISSN-Gold-OA 3.0 list, and OpenDOAR), the study confirms the growth of the OA share mirroring the international trend reported in related studies. We found that 45% of all considered articles during the observed period were openly available at the time of analysis. Our findings show that subject-specific repositories are the most prevalent type of OA. However, the percentages for publication in fully OA journals and OA via institutional repositories show similarly steep increases. Enabling data-driven decision-making regarding the implementation of OA in Germany at the institutional level, the results of this study furthermore can serve as a baseline to assess the impact recent transformative agreements with major publishers will likely have on scholarly communication.
  17. Lewandowski, D.; Mayr, P.: Exploring the academic invisible Web (2006) 0.00
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    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.
    Content
    Bezug zu: Bergman, M.K.: The Deep Web: surfacing hidden value. In: Journal of Electronic Publishing. 7(2001) no.1, S.xxx-xxx. [Vgl. unter: http://www.press.umich.edu/jep/07-01/bergman.html].
  18. Lewandowski, D.; Mayr, P.: Exploring the academic invisible Web (2006) 0.00
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    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.
  19. Momeni, F.; Mayr, P.: Analyzing the research output presented at European Networked Knowledge Organization Systems workshops (2000-2015) (2016) 0.00
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    Abstract
    In this paper we analyze a major part of the research output of the Networked Knowledge Organization Systems (NKOS) community in the period 2000 to 2015 from a network analytical perspective. We fo- cus on the paper output presented at the European NKOS workshops in the last 15 years. Our open dataset, the "NKOS bibliography", includes 14 workshop agendas (ECDL 2000-2010, TPDL 2011-2015) and 4 special issues on NKOS (2001, 2004, 2006 and 2015) which cover 171 papers with 218 distinct authors in total. A focus of the analysis is the visualization of co-authorship networks in this interdisciplinary eld. We used standard network analytic measures like degree and betweenness centrality to de- scribe the co-authorship distribution in our NKOS dataset. We can see in our dataset that 15% (with degree=0) of authors had no co-authorship with others and 53% of them had a maximum of 3 cooperations with other authors. 32% had at least 4 co-authors for all of their papers. The NKOS co-author network in the "NKOS bibliography" is a typical co- authorship network with one relatively large component, many smaller components and many isolated co-authorships or triples.
    Source
    Proceedings of the 15th European Networked Knowledge Organization Systems Workshop (NKOS 2016) co-located with the 20th International Conference on Theory and Practice of Digital Libraries 2016 (TPDL 2016), Hannover, Germany, September 9, 2016. Edi. by Philipp Mayr et al. [http://ceur-ws.org/Vol-1676/=urn:nbn:de:0074-1676-5]
  20. Mayr, P.: ¬Die virtuelle Steinsuppe : kooperatives Verwalten von elektronischen Ressourcen mit Digilink (2007) 0.00
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    Source
    Wa(h)re Information: 29. Österreichischer Bibliothekartag Bregenz, 19.-23.9.2006. Hrsg.: Harald Weigel