发表偏倚的原因、后果与预防研究   总被引：3，自引：0，他引：3  

杨扬  沈志超  靳纯桥 《编辑学报》2002,14(3):170-172

从4个方面对发表偏倚这一现象进行了研究: 1)发表偏倚的定义;2)发表偏倚产生的原因以及作者、编审者、资助者在选择性出版研究结果中所起的作用;3)发表偏倚的后果;4)发表偏倚的多项预防措施.  相似文献   

Assessing School Readiness: Validity and Bias in Preschool and Kindergarten Teachers' Ratings     

Andrew J. Mashburn  Gary T. Henry 《Educational Measurement》2004,23(4):16-30

As a part of efforts to evaluate and monitor the increasing public investment in early childhood education, teachers are being asked to assess children's school readiness. In this study, preschool teachers and kindergarten teachers rated children's skills in three areas (kindergarten readiness, academic skills, and communication skills), and these ratings were compared with direct assessments of the children's skills. Ratings by both groups of teachers tended to be more highly related to basic skills, such as counting and number naming, than to abilities such as solving applied problems and using expressive and receptive vocabulary. Preschool teachers' ratings had a lower association with children's observed skills and abilities than kindergarten teachers' ratings. Ratings of children attending Head Start were systematically inflated, but this relationship was mediated to a significant extent by the teachers' levels of education. More educated teachers rated children in a manner consistent with the children's directly assessed skills. Implications of these findings for informing future efforts to assess school readiness by using teacher ratings are discussed.  相似文献   

论数字图书馆基于内容的多媒体数据查询和检索技术   总被引：8，自引：0，他引：8  

赵一丹 《中国图书馆学报》2001,27(3)

数字图书馆基于内容的检索 (CBR) ,是指根据媒体对象的语义和上下文联系进行检索 ,它具有从媒体内容中提取信息检索和大型数据库 (集 )的快速检索等特征。基于内容的多媒体数据查询主要提供两种形式的查询说明 :示例查询说明和表格说明。图 1。参考文献 6。  相似文献   

XQuery——一种全新的XML查询语言   总被引：5，自引：0，他引：5  

金玉玲  陈培久  裘江南 《情报学报》2002,21(4):445-449

随着XML被广泛接受和使用 ,如何从XML数据源中准确有效地查询所需信息 ,也就变得越来越重要。本文介绍了一种全新XML查询语言—XQuery ,阐述了XQuery的结论、应用范围、支撑基础和应用前景  相似文献   

情报检索语言研究的新领域     

白华 《图书馆杂志》2006,25(11):3-6

情报检索语言的发展面临现代化、理论方法综合化和集成化的新条件,研究新的语言模型,提高检索语言的表达、描述等功能是当前的重要研究课题,同时要具体研究数据库检索语言、网络检索语言、本体论和语义网检索语言。在所有这些领域里,检索语言的机器理解功能日益重要;为适应机器处理的环境,对它的逻辑推理能力的要求越来越高,知识建模功能与系统表达能力受到越来越多的重视。  相似文献   

跨语言信息检索理论与应用研究   总被引：5，自引：0，他引：5  

郭宇锋  黄敏 《图书与情报》2006,35(2):79-81,84

随着互联网的全球化发展趋势，跨语言信息检索日益成为信息检索领域中的重要课题，跨语言检索可用一种提问语言检索出用另一种语言书写的信息。文章主要对跨语言信息检索理论应用研究进行了探讨，并对其在专业领域数据库中的应用提出一种思路。  相似文献   

Construction of query concepts based on feature clustering of documents     

Youjin Chang  Minkoo Kim  Vijay V. Raghavan 《Information Retrieval》2006,9(3):231-248

In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments. Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study, we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on TREC retrieval.  相似文献   

精确数据的模糊查询工具的设计与实现     总被引：1，自引：0，他引：1  

张婷 《现代图书情报技术》2004,20(12):36-39

针对人员信息管理的数据查询操作，在SQL语言中定义了模糊词隶属函数和语言算子隶属函数的函数及相关存储过程，以实现人员信息管理数据库的模糊查询。  相似文献   

Gender ratios at top PhD programs in economics     

《Economics of Education Review》2014

Analyzing university faculty and graduate students data for ten of the top U.S. economics departments between 1987 and 2007, we find persistent differences in the gender compositions of both faculty and graduate students across departments. There is a positive correlation between the share of female faculty and the share of women in the PhD class graduating six years later. Using instrumental variable analysis, we find robust evidence that this relation is causal. These results contribute to our understanding of the persistent under-representation of women in economics, as well as for the persistent segregation of women in the labor force.  相似文献   

The influence of heterogeneous exposure and pre-deliberation queries on pretrial publicity effects     

Jon Bruschke  Andrew Gonis III  Sarah A. Hill  Pam Fiber-Ostrow  William Loges 《Communication monographs》2016,83(4):521-534

Prior research on pretrial publicity has produced mixed results and a roughly equal number of studies show an effect, show no effect, or show mixed results. We explored the effects of (a) homogenous vs. heterogeneous exposure (whether deliberating jurors were all exposed to the same publicity or not) and (b) pre-deliberation queries as potential contributors to mixed results. We found an effect for positive but not negative publicity on conviction rates but not evidence ratings. Exposure heterogeneity appears to explain these differences and pre-deliberation queries did appear to play some role in the obtained outcomes. Overall these findings do not replicate a robust publicity effect and future research should consider how homogeneous exposure and pre-deliberation opinion queries influence results.  相似文献