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1.
Term discrimination values have been suggested as an effective means for the selection and weighting of index terms in automatic document retrieval systems. This paper reports an algorithm for the calculation of term discrimination values that is sufficiently fast in operation to permit the use of exact values, rather than the approximate values studied in previous work. Evidence is presented to show that the relationship between term discrimination and term frequency is crucially dependent upon the type of inter-document similarity measure that is used for the calculation of the discrimination values.  相似文献   
2.
A nearest neighbour search procedure is described for the automatic correction of misspellings. The procedure involves the replacement of a misspelt word by that word in a dictionary which best matches the misspelling, the degree of match being calculated using a similarity coefficient based on the number of trigrams common to the two words. Experiments with a collection of 1544 misspellings and a dictionary of 64,636 words suggest that the procedure results in the unique identification of the correct spelling for over 75% of the misspellings if the correct form of the word is in the dictionary, and that this figure may be increased to over 90% if near, rather than nearest, neighbours are acceptable.  相似文献   
3.
This paper studies the correlations between peer review and citation indicators when evaluating research quality in library and information science (LIS). Forty-two LIS experts provided judgments on a 5-point scale of the quality of research published by 101 scholars; the median rankings resulting from these judgments were then correlated with h-, g- and H-index values computed using three different sources of citation data: Web of Science (WoS), Scopus and Google Scholar (GS). The two variants of the basic h-index correlated more strongly with peer judgment than did the h-index itself; citation data from Scopus was more strongly correlated with the expert judgments than was data from GS, which in turn was more strongly correlated than data from WoS; correlations from a carefully cleaned version of GS data were little different from those obtained using swiftly gathered GS data; the indices from the citation databases resulted in broadly similar rankings of the LIS academics; GS disadvantaged researchers in bibliometrics compared to the other two citation database while WoS disadvantaged researchers in the more technical aspects of information retrieval; and experts from the UK and other European countries rated UK academics with higher scores than did experts from the USA.  相似文献   
4.
This paper is the first of two Learned Publishing articles in which we report the results of a series of interviews with senior publishers and editors exploring open access megajournals (OAMJs). Megajournals (of which PLoS One is the best known example) represent a relatively new approach to scholarly communication and can be characterized as large, broad‐scope, open access journals that take an innovative approach to peer review, basing acceptance decisions solely on the technical or scientific soundness of the article. This model is often said to support the broader goals of the open science movement. Based on in‐depth interviews with 31 publishers and editors representing 16 different organizations (10 of which publish a megajournal), this paper reports how the term ‘megajournal’ is understood and publishers’ rationale and motivations for launching (or not launching) an OAMJ. We find that while there is general agreement on the common characteristics of megajournals, there is not yet a consensus on their relative importance. We also find seven motivating factors that were said to drive the launch of an OAMJ and link each of these factors to potential societal and business benefits. These results suggest that the often polarized debate surrounding OAMJs is a consequence of the extent to which observers perceive publishers to be motivated by these societal or business benefits.  相似文献   
5.
This article reports findings from a study in which 26 girls aged 12‐ to 13‐years‐old took part in workshops at a specialist ICT centre connected to a school in inner‐city London. The girls explored and discussed fashion as presented online, and they produced their own interactive fashion design webpages, making decisions about body shapes, types of clothing and audience. The article analyses interview data, looking at statements girls made in the context of discursive practices around body image, pleasures of play and self‐confidence. The analysis examines the role of structure and agency in girls’ discussions about fashion media and argues that the agency offered to girls is structured by neoliberal discourses. As girls draw on these discourses, they enter into complex and often conflicting negotiations, rendering themselves as seemingly active agents who are making politicised arguments, and at the same time restricting their possible subject positions.  相似文献   
6.
This article uses data collected from a class of eight to nine year olds to show the specific ways children are defining their gendered positions within the context of their same sex friendship groups. Children's subjectivities are described as both actively formed and also positioned within the surrounding (gendered) discourses. This article will show specific ways that structure and agency is played out through talk amongst friends. Importantly, analysis of the talk indicates that children are able to both align themselves as well as challenge dominant gendered discourses. The article argues that informal talk amongst friends is an important space for children to make sense of masculinities and femininities and to develop their identities, particularly in the context of school.  相似文献   
7.
The authors examine the problems of ex-post evaluation of the benefits deriving from services provided by Government Laboratories. They concentrate on the difficulties of conducting meaningful ex-post studies since they feel that too many claims are made on the basis of inadequate, incomplete economic assessments using data that would not be substantiated if probed deeply. Their views are based on a review of nine years' practical evaluation experience.The paper defines three ways in which services/information sources can link up with intended recipients, and discusses the practical problems associated with assessing the impact of services in each case. These problems range from sampling errors and sample bias in questionnaire approaches, to limited respondent knowledge and perspective. Critical probing can overcome these difficulties in some, though not all, instances, since there are issues of principle that prohibit unique attribution of benefits to specific initiatives in many ex-post analyses. The use of cost recovery as a proxy measure of worth is reviewed.The authors point out that ex-ante appraisal of profits is not subject to the same constraints and avoids many of the pitfalls of ex-post evaluation.  相似文献   
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9.
A survey covering the scientific and social aspects of climate change was administered to examine U.S. undergraduate student mental models, and compare knowledge between groups based on major and environmental group membership. A Knowledge Score (scale 0–35, mean score = 17.84) was generated for respondents at two, central East Coast, U.S. universities (n = 465). Elements of student mental models examined include environmental issue confusion, skepticism, and self-reported understanding. This study finds that students frequently confuse climate change with other environmental issues, and that a substantial majority of students do not have an understanding of climate change that closely matches the scientific model. These misconceptions extend to their understanding of mitigation actions. Environmental group membership is shown to be a greater determinant of climate change knowledge than enrollment in a science major.  相似文献   
10.
An experimental best match retrieval system is described based on the serial file organisation. Documents and queries are characterised by fixed length bit strings and the time-consuming character-by-character term match is preceeded by a bit string search to eliminate large numbers of documents which cannot possibly satisfy the query. Two methods, one fully automatic and one partially manual in character, are described for the generation of such bit string characterisations. Retrieval experiments with a large document test collection show that the two-level search can increase substantially the efficiency of serial searching while maintaining retrieval effectiveness, and that a single-level search based only upon the bit strings results in only a small decrease in effectiveness in some cases.  相似文献   
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