From Retrieval Status Values to Probabilities of Relevance for Advanced IR Applications     

Henrik Nottelmann  Norbert Fuhr 《Information Retrieval》2003,6(3-4):363-388

Information Retrieval systems typically sort the result with respect to document retrieval status values (RSV). According to the Probability Ranking Principle, this ranking ensures optimum retrieval quality if the RSVs are monotonously increasing with the probabilities of relevance (as e.g. for probabilistic IR models). However, advanced applications like filtering or distributed retrieval require estimates of the actual probability of relevance. The relationship between the RSV of a document and its probability of relevance can be described by a normalisation function which maps the retrieval status value onto the probability of relevance (mapping functions). In this paper, we explore the use of linear and logistic mapping functions for different retrieval methods. In a series of upper-bound experiments, we compare the approximation quality of the different mapping functions. We also investigate the effect on the resulting retrieval quality in distributed retrieval (only merging, without resource selection). These experiments show that good estimates of the actual probability of relevance can be achieved, and that the logistic model outperforms the linear one. Retrieval quality for distributed retrieval is only slightly improved by using the logistic function.  相似文献   

Schwerpunkt: Bildungsökonomie     

Norbert Neumann 《Zeitschrift für Erziehungswissenschaft》2008,11(2):165-167

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Harmonic analysis and the quantum theory     

Norbert Wiener 《Journal of The Franklin Institute》1929,207(4):525-534

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A first-language-first multilingual model to meet the quality imperative in formal basic education in three ‘francophone’ West African countries     

Norbert Nikièma 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2011,38(2):599-616

This paper documents the new trend towards a first-language-first multilingual model in formal education in three former French colonies of West Africa, namely Burkina Faso, Mali and Niger. It compares the sociolinguistic situations, the conditions of the development of multilingual education and the achievements of mother-tongue-medium education in all three countries. The evidence is that, contrary to common discourse in francophonie, a strong first-language-first model in formal education is the best guarantee of a good mastery of French and, more generally, of quality education in francophone countries.  相似文献   

Bringing together acculturation theory and intergroup contact theory: Predictors of Flemings’ expectations of Turks’ acculturation behavior     

Kaat Van Acker  Norbert Vanbeselaere 《Int J Intercult Relat》2011,35(3):334-345

The present paper explores Flemish majority members’ expectations concerning the acculturation of Turkish minorities. We studied two kinds of antecedents: majority members’ perceptions of Turkish minorities’ acculturation behavior and their experiences of intergroup contact. The possible mediating role of outgroup affect was also investigated. 247 Flemish high school students completed a survey. Data were analyzed using path analyses. Results show that positive contact experiences and perceiving that Turkish immigrants make efforts to engage in contact with the host group and/or to adopt the host culture are associated with less negative affective reactions towards Turkish migrants. Perceiving that Turkish immigrants maintain their heritage culture is associated with more negative affective reactions. Our results further revealed that increased negative affective reactions are associated with less support for culture maintenance and for contact with the host group but with a higher demand for host culture adoption. The present results also show that expectations of contact engagement and expectations of host culture adoption cannot be considered as equivalent. This implies that results from studies using Berry's conceptualization of acculturation expectations (Berry, 2001) and results from studies using Bourhis’ conceptualization of acculturation expectations (Bourhis, Moïse, Perreault, & Senécal, 1997) are not directly comparable. Our data also clearly disconfirm the orthogonal structure of the fourfold acculturation model for majority members’ acculturation expectations, suggesting that relying on the specific dimensions defining acculturation expectations may constitute a more valid approach to understand ongoing acculturation processes.  相似文献   

Sport und Spannung im Prozess der Zivilisation     

Norbert Elias  Eric Dunning  Michael Krüger 《Sportwissenschaft》2003,33(4):473-478

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THE DEPICTION OF SEX ROLES IN AMERICAN AND GERMAN MAGAZINE ADVERTISEMENTS*     

Brosius  Hans-Bernd; Mundorf  Norbert; Staab  Joachim F. 《Int. Journal of Public Opinion Research》1991,3(4):366-383

This study provides a quantitative content analysis of the depictionsof sex roles in the American news magazine Time and the WestGerman news magazine Stern from 1969 to 1988. The underlyingassumption of the study is that advertisements reflect changesin social reality. While most studies focus on explicit aspectsof gender role depictions such as jobs, activities, interactionsand situations, this content analysis also covers implicit aspectsof role depictions such as posture, gestures, and facial expression.Some authors have claimed that these are powerful means of transmittingtraditional sex role stereotypes of women as being submissiveand of men as being dominant. Results indicate that while therehave been considerable changes in the explicit presentationof male and female roles, the implicit presentation remainedquite consistent over the 20-year period. According to thesefindings, sex roles may have changed primarily on the surface,while nonverbal sex role stereotypes still linger on. Differencesbetween the developments in Germany and the US are outlined.  相似文献   

Introduction to the Special Issue on INEX     

Norbert?FuhrEmail author  Mounia?Lalmas 《Information Retrieval》2005,8(4):515-519

This special issue contains articles describing XML retrieval approaches developed and evaluated during the second year of INEX, the evaluation initiative for XML retrieval.  相似文献   

The nature of the phonological processing in French dyslexic children: evidence for the phonological syllable and linguistic features' role in silent reading and speech discrimination     

Norbert Ma?onchi-Pino  Annie Magnan  Jean écalle 《Annals of dyslexia》2010,60(2):123-150

This study investigated the status of phonological representations in French dyslexic children (DY) compared with reading level- (RL) and chronological age-matched (CA) controls. We focused on the syllable’s role and on the impact of French linguistic features. In Experiment 1, we assessed oral discrimination abilities of pairs of syllables that varied as a function of voicing, mode or place of articulation, or syllable structure. Results suggest that DY children underperform controls with a ‘speed-accuracy’ deficit. However, DY children exhibit some similar processing than those highlighted in controls. As in CA and RL controls, DY children have difficulties in processing two sounds that only differ in voicing, and preferentially process obstruent rather than fricative sounds, and more efficiently process CV than CCV syllables. In Experiment 2, we used a modified version of the Colé, Magnan, and Grainger's (Applied Psycholinguistics 20:507–532, 1999) paradigm. Results show that DY children underperform CA controls but outperform RL controls. However, as in CA and RL controls, data reveal that DY children are able to use phonological procedures influenced by initial syllable frequency. Thus, DY children process syllabically high-frequency syllables but phonemically process low-frequency syllables. They also exhibit lexical and syllable frequency effects. Consequently, results provide evidence that DY children performances can be accounted for by laborious phonological syllable-based procedures and also degraded phonological representations.  相似文献   

Effect of Strenuous Physical Activity upon Reaction Time     

Carlton R. Meyers  William Zimmerli  S. David Farr  Norbert A. Baschnagel 《Research quarterly for exercise and sport》2013,84(2):332-337

Abstract

This study was concerned with the effect of bench-stepping in the Harvard Step Test upon finger and foot reaction time and, secondarily, with ascertaining the relationship, if any, between these reaction times and scores on the Harvard Step Test. The subjects were university freshman males. Reaction times were taken before, immediately after, and four minutes after the stepping exercise for 80 subjects. Thirty-six subjects served as controls, involving the reaction times and pulse counts at the prescribed intervals but without exercise. The findings failed to divulge any discernible effect of stepping exercise upon reaction time, or any apparent relationship between reaction time and the sum of the recovery pulse counts following the exercise. In view of these findings it is suggested that study be directed to two related aspects — the effect of exercise to exhaustion on reaction time, and the effect of strenuous and exhaustive exercise upon speed of movement.  相似文献