Search (16 results, page 1 of 1)

  • × author_ss:"Lewandowski, D."
  • × year_i:[2010 TO 2020}
  1. Lewandowski, D.: Query understanding (2011) 0.05 
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    Date
    18. 9.2018 18:22:18
    Source
    Handbuch Internet-Suchmaschinen, 2: Neue Entwicklungen in der Web-Suche. Hrsg.: D. Lewandowski
  2. Lewandowski, D.: Perspektiven eines Open Web Index (2016) 0.02 
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    Abstract
    Der Suchmaschinenmarkt wird seit vielen Jahren von nur einer einzigen Suchmaschine, Google, dominiert. Es wurde mittlerweile erkannt, dass diese Situation nicht wünschenswert ist. Wir sprechen nun über mögliche Lösungen. Der Artikel diskutiert unterschiedliche Lösungsansätze und fokussiert dabei auf die Idee einen Offenen Web-Index (OWI), der als öffentliche Infrastruktur verfügbar gemacht werden soll. Die Grundidee ist die Trennung von Datenbestand (Index) und darauf aufsetzenden Diensten, welche in großer Zahl in privater Initiative betrieben werden können. Es geht also darum, die Basis für Vielfalt zu schaffen.
  3. Schaer, P.; Mayr, P.; Sünkler, S.; Lewandowski, D.: How relevant is the long tail? : a relevance assessment study on million short (2016) 0.01 
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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.
  4. Lewandowski, D.; Sünkler, S.: ¬Das Relevance Assessment Tool : eine modulare Software zur Unterstützung bei der Durchführung vielfältiger Studien mit Suchmaschinen (2019) 0.01 
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    Abstract
    In diesem Artikel stellen wir eine Software vor, mit der sich Studien zu Such- und Informationssystemen realisieren lassen. Das Relevance Assessment Tool (RAT) soll umfangreiche Untersuchungen mit Daten von kommerziellen Suchmaschinen unterstützen. Die Software ist modular und webbasiert. Es lassen sich damit automatisiert Daten von Suchmaschinen erfassen. Dazu können Studien mit Fragen und Skalen flexibel gestaltet und die Informationsobjekte anhand der Fragen durch Juroren bewertet werden. Durch die Modularität lassen sich die einzelnen Komponenten für eine Vielzahl von Studien nutzen, die sich auf Web-Inhalte beziehen. So kann die Software auch für qualitative Inhaltsanalysen eingesetzt werden oder durch das automatisierte Scraping eine große Datenbasis an Web-Dokumenten liefern, die sich quantitativ in empirischen Studien analysieren lassen.
  5. Lewandowski, D.: Evaluierung von Suchmaschinen (2011) 0.01 
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    Source
    Handbuch Internet-Suchmaschinen, 2: Neue Entwicklungen in der Web-Suche. Hrsg.: D. Lewandowski
  6. Lewandowski, D.; Drechsler, J.; Mach, S. von: Deriving query intents from web search engine queries (2012) 0.01 
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    Abstract
    The purpose of this article is to test the reliability of query intents derived from queries, either by the user who entered the query or by another juror. We report the findings of three studies. First, we conducted a large-scale classification study (~50,000 queries) using a crowdsourcing approach. Next, we used clickthrough data from a search engine log and validated the judgments given by the jurors from the crowdsourcing study. Finally, we conducted an online survey on a commercial search engine's portal. Because we used the same queries for all three studies, we also were able to compare the results and the effectiveness of the different approaches. We found that neither the crowdsourcing approach, using jurors who classified queries originating from other users, nor the questionnaire approach, using searchers who were asked about their own query that they just entered into a Web search engine, led to satisfying results. This leads us to conclude that there was little understanding of the classification tasks, even though both groups of jurors were given detailed instructions. Although we used manual classification, our research also has important implications for automatic classification. We must question the success of approaches using automatic classification and comparing its performance to a baseline from human jurors.
  7. Behnert, C.; Lewandowski, D.: ¬A framework for designing retrieval effectiveness studies of library information systems using human relevance assessments (2017) 0.01 
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    Abstract
    Purpose This paper demonstrates how to apply traditional information retrieval evaluation methods based on standards from the Text REtrieval Conference (TREC) and web search evaluation to all types of modern library information systems including online public access catalogs, discovery systems, and digital libraries that provide web search features to gather information from heterogeneous sources. Design/methodology/approach We apply conventional procedures from information retrieval evaluation to the library information system context considering the specific characteristics of modern library materials. Findings We introduce a framework consisting of five parts: (1) search queries, (2) search results, (3) assessors, (4) testing, and (5) data analysis. We show how to deal with comparability problems resulting from diverse document types, e.g., electronic articles vs. printed monographs and what issues need to be considered for retrieval tests in the library context. Practical implications The framework can be used as a guideline for conducting retrieval effectiveness studies in the library context. Originality/value Although a considerable amount of research has been done on information retrieval evaluation, and standards for conducting retrieval effectiveness studies do exist, to our knowledge this is the first attempt to provide a systematic framework for evaluating the retrieval effectiveness of twenty-first-century library information systems. We demonstrate which issues must be considered and what decisions must be made by researchers prior to a retrieval test.
  8. Behnert, C.; Plassmeier, K.; Borst, T.; Lewandowski, D.: Evaluierung von Rankingverfahren für bibliothekarische Informationssysteme (2019) 0.01 
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    Abstract
    Dieser Beitrag beschreibt eine Studie zur Entwicklung und Evaluierung von Rankingverfahren für bibliothekarische Informationssysteme. Dazu wurden mögliche Faktoren für das Relevanzranking ausgehend von den Verfahren in Websuchmaschinen identifiziert, auf den Bibliothekskontext übertragen und systematisch evaluiert. Mithilfe eines Testsystems, das auf dem ZBW-Informationsportal EconBiz und einer web-basierten Software zur Evaluierung von Suchsystemen aufsetzt, wurden verschiedene Relevanzfaktoren (z. B. Popularität in Verbindung mit Aktualität) getestet. Obwohl die getesteten Rankingverfahren auf einer theoretischen Ebene divers sind, konnten keine einheitlichen Verbesserungen gegenüber den Baseline-Rankings gemessen werden. Die Ergebnisse deuten darauf hin, dass eine Adaptierung des Rankings auf individuelle Nutzer bzw. Nutzungskontexte notwendig sein könnte, um eine höhere Performance zu erzielen.
  9. Lewandowski, D.: ¬Die Macht der Suchmaschinen und ihr Einfluss auf unsere Entscheidungen (2014) 0.01 
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    Date
    22. 9.2014 18:54:11
  10. Lewandowski, D.: ¬A framework for evaluating the retrieval effectiveness of search engines (2012) 0.01 
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    Abstract
    This chapter presents a theoretical framework for evaluating next generation search engines. The author focuses on search engines whose results presentation is enriched with additional information and does not merely present the usual list of "10 blue links," that is, of ten links to results, accompanied by a short description. While Web search is used as an example here, the framework can easily be applied to search engines in any other area. The framework not only addresses the results presentation, but also takes into account an extension of the general design of retrieval effectiveness tests. The chapter examines the ways in which this design might influence the results of such studies and how a reliable test is best designed.
  11. Lewandowski, D.: Evaluating the retrieval effectiveness of web search engines using a representative query sample (2015) 0.01 
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  12. Lewandowski, D.; Krewinkel, A.; Gleissner, M.; Osterode, D.; Tolg, B.; Holle, M.; Sünkler, S.: Entwicklung und Anwendung einer Software zur automatisierten Kontrolle des Lebensmittelmarktes im Internet mit informationswissenschaftlichen Methoden (2019) 0.01 
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    Abstract
    In diesem Artikel präsentieren wir die Durchführung und die Ergebnisse eines interdisziplinären Forschungsprojekts zum Thema automatisierte Lebensmittelkontrolle im Web. Es wurden Kompetenzen aus den Disziplinen Lebensmittelwissenschaft, Rechtswissenschaft, Informationswissenschaft und Informatik dazu genutzt, ein detailliertes Konzept und einen Software-Prototypen zu entwickeln, um das Internet nach Produktangeboten zu durchsuchen, die gegen das Lebensmittelrecht verstoßen. Dabei wird deutlich, wie ein solcher Anwendungsfall von den Methoden der Information-Retrieval-Evaluierung profitiert, und wie sich mit relativ geringem Aufwand eine flexible Software programmieren lässt, die auch für eine Vielzahl anderer Fragestellungen einsetzbar ist. Die Ergebnisse des Projekts zeigen, wie komplexe Arbeitsprozesse einer Behörde mit Hilfe der Methoden von Retrieval-Tests und gängigen Verfahren aus dem maschinellen Lernen effektiv und effizient unterstützt werden können.
  13. Lewandowski, D.: Suchmaschinen verstehen (2015) 0.01 
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    Abstract
    Das Buch betrachtet das Thema Suchmaschinen ausgehend von der täglichen Recherche und führt in die technischen Grundlagen, in Recherchetechniken sowie die gesellschaftlichen und wirtschaftlichen Bedingungen der Recherche im Web ein. Suchmaschinen sind heute die wichtigsten Werkzeuge, um an Informationen zu gelangen. Wir verwenden Suchmaschinen täglich, meist ohne weiter darüber nachzudenken. Doch wie funktionieren diese Suchwerkzeuge eigentlich genau? Neben einer ausführlichen Darstellung der in den bekannten Suchmaschinen verwendeten Rankingverfahren wird auch ausführlich auf das Nutzerverhalten eingegangen, das wiederum die Ergebnisdarstellung prägt. Dazu kommen grundlegende Betrachtungen des Suchmaschinenmarkts, der Bedeutung der Suchmaschinenoptimierung und der Rolle der Suchmaschinen als technische Informationsvermittler. Nicht zuletzt wird auch die Seite der Recherche betrachtet und gezeigt, wie man mit den bekannten Suchmaschinen effizient recherchieren kann. Das Buch verhilft allen, die mit Suchmaschinen recherchieren oder sich beruflich mit der Optimierung, Aufbereitung und Sichtbarmachung von Inhalten beschäftigen, zu einem umfassenden Verständnis der Ansätze, Stärken und Schwächen verschiedener Suchmaschinen und der ihnen zugrunde liegenden Technologien.
  14. Lewandowski, D.; Spree, U.: Ranking of Wikipedia articles in search engines revisited : fair ranking for reasonable quality? (2011) 0.01 
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    Date
    30. 9.2012 19:27:22
  15. Lewandowski, D.; Sünkler, S.: What does Google recommend when you want to compare insurance offerings? (2019) 0.01 
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    Date
    20. 1.2015 18:30:22
  16. Lewandowski, D.: ¬The retrieval effectiveness of search engines on navigational queries (2011) 0.01 
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    Abstract
    Purpose - The purpose of this paper is to test major web search engines on their performance on navigational queries, i.e. searches for homepages. Design/methodology/approach - In total, 100 user queries are posed to six search engines (Google, Yahoo!, MSN, Ask, Seekport, and Exalead). Users described the desired pages, and the results position of these was recorded. Measured success and mean reciprocal rank are calculated. Findings - The performance of the major search engines Google, Yahoo!, and MSN was found to be the best, with around 90 per cent of queries answered correctly. Ask and Exalead performed worse but received good scores as well. Research limitations/implications - All queries were in German, and the German-language interfaces of the search engines were used. Therefore, the results are only valid for German queries. Practical implications - When designing a search engine to compete with the major search engines, care should be taken on the performance on navigational queries. Users can be influenced easily in their quality ratings of search engines based on this performance. Originality/value - This study systematically compares the major search engines on navigational queries and compares the findings with studies on the retrieval effectiveness of the engines on informational queries.

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