Measuring Search Engine Quality   总被引：12，自引：3，他引：9  

David Hawking  Nick Craswell  Peter Bailey  Kathleen Griffihs 《Information Retrieval》2001,4(1):33-59

The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.  相似文献   

The Provision for Personal, Social, Health Education (PSHE) and Citizenship in School-based Elements of Primary Initial Teacher Education     

Nick Mead 《Pastoral Care in Education》2004,22(2):19-26

This small-scale research study looks at the PSHE/Citizenship framework and the opportunities for student teachers to understand and experience within school the relationship between values, personal and social development and learning. A questionnaire was given to two sets of student teachers on their final school-based placements. The research suggests that there needs to be greater recognition of the centrality of multi-cultural awareness and understanding within the political literacy section of the PSHE/Citizenship framework. This is the counterpart to a previous study of the opportunities for values education within the university-based elements of Primary Initial Teacher Education ( Mead, 2003 ).  相似文献   

Planning for the future: learning from the past     

Nick Gibbs Director of Community Services 《Cultural Trends》2004,13(3):37-39

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Public library trends     

Nick Moore 《Cultural Trends》2004,13(1):27-57

Public libraries tend to be taken for granted. They can be found in nearly every community and are used by a substantial proportion of the population, particularly the young and the old. Yet the public library service, as it is today, is a relatively recent phenomenon. Despite their origins in the mid-19th century, the widespread network of public libraries is largely the product of the post-war welfare state. The demand for the service grew rapidly during the war and in the immediate post-war period. Provision to meet the demand was constrained initially by the competing demands for reconstruction, but by 1960 the service was ready to expand. The growth was consolidated by the 1964 Public Libraries and Museums Act and was given further emphasis by the 1962 Bourdillon standards (Ministry of Education, 1962). The Act and the standards provided the impetus for what might be described as the golden age of public libraries. This brief period was brought to an abrupt end by the economic crises of the mid-1970s and the subsequent downward pressure on public expenditure. The service managed to hold its own during the late 1970s and early 1980s but since then it has been in decline, with the rate of decline accelerating during the 1990s as new requirements and increasing costs stretched diminishing resources even further, to the point where the overall level of provision now falls well short of the basic standards that were considered to be essential in the early 1960s.  相似文献   

Quality and relevance of domain-specific search: A case study in mental health     

Thanh Tin Tang  Nick Craswell  David Hawking  Kathy Griffiths  Helen Christensen 《Information Retrieval》2006,9(2):207-225

When searching for health information, results quality can be judged against available scientific evidence: Do search engines return advice consistent with evidence based medicine? We compared the performance of domain-specific health and depression search engines against a general-purpose engine (Google) on both relevance of results and quality of advice. Over 101 queries, to which the term ‘depression’ was added if not already present, Google returned more relevant results than those of the domain-specific engines. However, over the 50 treatment-related queries, Google returned 70 pages recommending for or against a well studied treatment, of which 19 strongly disagreed with the scientific evidence. A domain-specific index of 4 sites selected by domain experts was only wrong in 5 of 50 recommendations. Analysis suggests a tension between relevance and quality. Indexing more pages can give a greater number of relevant results, but selective inclusion can give better quality.  相似文献   

Teach the Medium     

Nick Jaffe 《Teaching Artist Journal》2015,13(1):3-4

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Researching teaching for understanding: the students’ perspective     

John Loughran  Nick Derry 《International Journal of Science Education》2013,35(8):925-938

Abstract

This paper explores high school students’ perspectives of their learning in ascience unit which was taught using a Children's Science approach. Through the use of a questionnaire and interviews, this research examines how the students understood and responded to the changed demands on their learning as a result of the change in teaching style. Although the students appeared to be actively involved, interested and self‐directed in their learning, they were not convinced that this was an appropriate way forthem to approach their learning in future. It appears as though the time and effort associated with accepting more responsibility for learning is not matched by the value received from doing so in schools.  相似文献   

Editorial: On being an editor          下载免费PDF全文

Nick Rushby 《British journal of educational technology : journal of the Council for Educational Technology》2015,46(4):681-683

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How Can I Tell the Truth?     

Nick Eastmond  Robert Hayden 《TechTrends》2006,50(3):13-13

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弗里德曼:使社会倒退的"自由市场"设计师     

尼克·比姆斯  李春兰 《高校理论战线》2007,(4):28-31

2006年11月21日,澳大利亚http://www.wsws.org网站刊登了尼克·比姆斯题为《弗里德曼:使社会倒退的"自由市场"设计师》的文章,认为弗里德曼的理论受到重视不是因为其科学性,而是因为他为垄断资本的全球扩张提供了一个意识形态外衣,他的理论在科学上是一种倒退,而且实际上也导致社会倒退.文章主要内容如下.  相似文献