Search (8 results, page 1 of 1)

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Footnote

Rez. in: JASIST 58(2007) no.4, S.608-609 (K.D. Desouza): "Richard Rogers explores the distinctiveness of the World Wide Web as a politically contested space where information searchers may encounter multiple explanations of reality. Sources of information on the Web are in constant competition with each other for attention. The attention a source receives will determine its prominence, the ability to be a provider of leading information, and its inclusion in authoritative spaces. Rogers explores the politics behind evaluating sources that are collected and housed on authoritative spaces. Information politics on the Web can be looked at in terms of frontend or back-end politics. Front-end politics is concerned with whether sources on the Web pay attention to principles of inclusivity, fairness, and scope of representation in how information is presented, while back-end politics examines the logic behind how search engines or portals select and index information. Concerning front-end politics, Rogers questions the various versions of reality one can derive from examining information on the Web, especially when issues of information inclusivity and scope of representation are toiled with. In addition, Rogers is concerned with how back-end politics are being controlled by dominant forces of the market (i.e., the more an organization is willing to pay, the greater will be the site's visibility and prominence in authoritative spaces), regardless of whether the information presented on the site justifies such a placement. In the book, Rogers illustrates the issues involved in back-end and front-end politics (though heavily slanted on front-end politics) using vivid cases, all of which are derived from his own research. The main thrust is the exploration of how various "information instruments," defined as "a digital and analytical means of recording (capturing) and subsequently reading indications of states of defined information streams (p. 19)," help capture the politics of the Web. Rogers employs four specific instruments (Lay Decision Support System, Issue Barometer, Web Issue Index of Civil Society, and Election Issue Tracker), which are covered in detail in core chapters of the book (Chapter 2-Chapter 5). The book is comprised of six chapters, with Chapter 1 being the traditional introduction and Chapter 6 being a summary of the major concepts discussed.
Chapter 2 examines the politics of information retrieval in the context of collaborative filtering techniques. Rogers begins by discussing the underpinnings of modern search engine design by examining medieval practices of knowledge seeking, following up with a critique of the collaborative filtering techniques. Rogers's major contention is that collaborative filtering rids us of user idiosyncrasies as search query strings, preferences, and recommendations are shared among users and without much care for the differences among them, both in terms of their innate characteristics and also their search goals. To illustrate Rogers' critiques of collaborative filtering, he describes an information searching experiment that he conducted with students at University of Vienna and University of Amsterdam. Students were asked to search for information on Viagra. As one can imagine, depending on a number of issues, not the least of which is what sources did one extract information from, a student would find different accounts of reality about Viagra, everything from a medical drug to a black-market drug ideal for underground trade. Rogers described how information on the Web differed from official accounts for certain events. The information on the Web served as an alternative reality. Chapter 3 describes the Web as a dynamic debate-mapping tool, a political instrument. Rogers introduces the "Issue Barometer," an information instrument that measures the social pressure on a topic being debated by analyzing data available from the Web. Measures used by the Issue Barometer include temperature of the issue (cold to hot), activity level of the debate (mild to intense), and territorialization (one country to many countries). The Issues Barometer is applied to an illustrative case of the public debate surrounding food safety in the Netherlands in 2001. Chapter 4 introduces "The Web Issue Index," which provides an indication of leading societal issues discussed on the Web. The empirical research on the Web Issues Index was conducted on the Genoa G8 Summit in 1999 and the anti-globalization movement. Rogers focus here was to examine the changing nature of prominent issues over time, i.e., how issues gained and lost attention and traction over time.

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Content

Inhalt: Boolean retrieval - The term vocabulary & postings lists - Dictionaries and tolerant retrieval - Index construction - Index compression - Scoring, term weighting & the vector space model - Computing scores in a complete search system - Evaluation in information retrieval - Relevance feedback & query expansion - XML retrieval - Probabilistic information retrieval - Language models for information retrieval - Text classification & Naive Bayes - Vector space classification - Support vector machines & machine learning on documents - Flat clustering - Hierarchical clustering - Matrix decompositions & latent semantic indexing - Web search basics - Web crawling and indexes - Link analysis Vgl. die digitale Fassung unter: http://nlp.stanford.edu/IR-book/pdf/irbookprint.pdf.

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RSWK

Suchmaschine / Information-Retrieval-System / Optimierung

Subject

Suchmaschine / Information-Retrieval-System / Optimierung

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RSWK

Suchmaschine / Information Retrieval / Ranking / Datenstruktur / Kontextbezogenes System

Subject

Suchmaschine / Information Retrieval / Ranking / Datenstruktur / Kontextbezogenes System

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Footnote

Rez. in: Wechselwirkung 26(2004) Nr.128, S.110: "Dieses Buch zeigt die vielfältigen Möglichkeiten, die ein Intranet-Einsatz dem Unternehmen bietet - angefangen vom Firmeninformations system bis zum Einsatz in Form des Extranet als Basis für Workflow und Wissensmanagement. Dabei wird deutlich, dass ein Intranet von enormer strategischer Bedeutung für die Informationsverarbeitung des gesamten Unternehmens ist. Der Autor Carl Hans Block behandelt neben den Grundlagen, die ein Intranet-Einsatz erfordert, insbesondere das praktische Vorgehen sowohl bei der Erstellung als auch beim laufenden Betrieb des Intranet."

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RSWK

Semantic Web / Information Extraction / Suche / Wissensbasiertes System / Aufsatzsammlung

Subject

Semantic Web / Information Extraction / Suche / Wissensbasiertes System / Aufsatzsammlung

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Date

12. 2.2011 17:29:27

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Date

22. 3.2008 16:18:27