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   

电动跑台对提高竞走运动员步频的研究   总被引：5，自引：0，他引：5  

王林  郑沪娥 《中国体育科技》2003,39(10):57-59

采用竞走运动员无氧阈值速度的测定与应用方法 ,分别对运动员进行 3个阶段逐级提高速度的跑台竞走实验 ,经过统计学处理和实际比赛的对比 ,结果表明 :利用电动跑台进行辅助训练 ,可以加快发展竞走运动员的动作速率 ,有效提高竞走运动员的步频 ,创造优异成绩。  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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田径教学训练大纲综合评定软件的研制     

黄化礼  章碧玉  陈美仪 《北京体育大学学报》1992,(4)

在IBM—PC/XT286及其兼容机上,在UCDOS 支持下,以汉字DBASE-Ⅲ语言编写而成。主要包括:使用信息、运动员成绩计算及打印、运动员成绩查询与打印。测试运动员年龄段为13～17岁。测试项目为短跑、中长跑、竞走、跨栏、跳高、跳远、三级跳远(男)、撑竿跳高(男)、铅球、标枪、铁饼、链球(男)。软件的研制成功,大大提高了田径教学训练大纲综合评定的运算速度,避免了人工计算时可能出现的错误,是大纲测试有力助手。  相似文献   

湖南省田径队男子三级跳远成功的启示     

谢朝辉  熊卫  钟大鹏 《湖北体育科技》2003,22(1):93-94,96

通过湖北省田径队优秀男子三级跳远运动员熊卫在湖南省田径队男子三级跳远组训练过程的分析，认为教练员科学的、极具鲜明特点的训练方法，以及与运动员团结协作，努力拼搏，无私奉献的敬业精神，是湖南省男子三级跳远取得成功的关键。  相似文献   

TFPS 教学用运动技术影片分析系统的教学应用     

吕秋平  沈信生  李良标 《北京体育大学学报》1993,(3)

TFPS 教学用运动技术影片分析系统(Teaching's Film Processing System)的应用,彻底改变了以往影片分析方法教学的一般性介绍的状况,以实验部分为核心,采用新的教学方法,借助新的教学仪器,使理论与实践相结合,大大加深了学生对这一方法的理论知识的理解和掌握,同时使学生亲自动手实验,掌握实际实验技能,大大提高了进行运动技术分析的研究能力,填补了这一教学领域的空白,使这一领域的教学水平和教学质量达到了国内领先水平和国际先进水平。  相似文献   

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   

The Beaumont letters     

Field W 《The Yale University library gazette. Yale University. Library》1985,60(1-2):58-62

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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