Search (32 results, page 1 of 2)

  • × author_ss:"Mayr, P."
  1. Mayr, P.; Petras, V.: Building a Terminology Network for Search : the KoMoHe project (2008) 0.02 
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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
    Type
    a
  2. 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) 0.02 
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    Date
    8. 7.2006 21:06:22
    Type
    a
  3. Reichert, S.; Mayr, P.: Untersuchung von Relevanzeigenschaften in einem kontrollierten Eyetracking-Experiment (2012) 0.02 
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    Date
    22. 7.2012 19:25:54
    Type
    a
  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
    Type
    a
  5. Mayr, P.; Scharnhorst, A.: Scientometrics and information retrieval - weak-links revitalized (2015) 0.00 
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  6. Mayr, P.; Petras, V.; Walter, A.-K.: Results from a German terminology mapping effort : intra- and interdisciplinary cross-concordances between controlled vocabularies (2007) 0.00 
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    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.
  7. Mutschke, P.; Mayr, P.: Science models for search : a study on combining scholarly information retrieval and scientometrics (2015) 0.00 
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  8. Carevic, Z.; Krichel, T.; Mayr, P.: Assessing a human mediated current awareness service (2015) 0.00 
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  9. Mayr, P.; Mutschke, P.; Petras, V.; Schaer, P.; Sure, Y.: Applying science models for search (2010) 0.00 
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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.
    Type
    a
  10. Daquino, M.; Peroni, S.; Shotton, D.; Colavizza, G.; Ghavimi, B.; Lauscher, A.; Mayr, P.; Romanello, M.; Zumstein, P.: ¬The OpenCitations Data Model (2020) 0.00 
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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.
    Type
    a
  11. 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.
    Type
    a
  12. Mayr, P.; Schaer, P.; Mutschke, P.: ¬A science model driven retrieval prototype (2011) 0.00 
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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.
    Type
    a
  13. 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.
    Type
    a
  14. Schaer, P.; Mayr, P.; Sünkler, S.; Lewandowski, D.: How relevant is the long tail? : a relevance assessment study on million short (2016) 0.00 
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    Abstract
    Users of web search engines are known to mostly focus on the top ranked results of the search engine result page. While many studies support this well known information seeking pattern only few studies concentrate on the question what users are missing by neglecting lower ranked results. To learn more about the relevance distributions in the so-called long tail we conducted a relevance assessment study with the Million Short long-tail web search engine. While we see a clear difference in the content between the head and the tail of the search engine result list we see no statistical significant differences in the binary relevance judgments and weak significant differences when using graded relevance. The tail contains different but still valuable results. We argue that the long tail can be a rich source for the diversification of web search engine result lists but it needs more evaluation to clearly describe the differences.
    Type
    a
  15. 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.
  16. Mayr, P.; Mutschke, P.; Petras, V.: Reducing semantic complexity in distributed digital libraries : Treatment of term vagueness and document re-ranking (2008) 0.00 
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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.
    Type
    a
  17. 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.
    Type
    a
  18. 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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    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.
    Type
    a
  19. Mayr, P.; Walter, A.-K.: Abdeckung und Aktualität des Suchdienstes Google Scholar (2006) 0.00 
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  20. Mayr, P.: Thesauri, Klassifikationen & Co - die Renaissance der kontrollierten Vokabulare? (2006) 0.00 
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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.
    Type
    a

Authors

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Languages

  • e 16
  • d 15

Types

Themes