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91.
Indexing consistency in MEDLINE 总被引:3,自引:0,他引:3
The quality of indexing of periodicals in a bibliographic data base cannot be measured directly, as there is no one "correct" way to index an item. However, consistency can be used to measure the reliability of indexing. To measure consistency in MEDLINE, 760 twice-indexed articles from 42 periodical issues were identified in the data base, and their indexing compared. Consistency, expressed as a percentage, was measured using Hooper's equation. Overall, checktags had the highest consistency. Medical Subject Headings (MeSH) and subheadings were applied more consistently to central concepts than to peripheral points. When subheadings were added to a main heading, consistency was lowered. "Floating" subheadings were more consistent than were attached subheadings. Indexing consistency was not affected by journal indexing priority, language, or length of the article. Terms from MeSH Tree Structure categories A, B, and D appeared more often than expected in the high-consistency articles; whereas terms from categories E, F, H, and N appeared more often than expected in the low-consistency articles. MEDLINE, with its excellent controlled vocabulary, exemplary quality control, and highly trained indexers, probably represents the state of the art in manually indexed data bases. 相似文献
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D A Kronick 《Bulletin of the Medical Library Association》1979,67(3):297-301
A cooperative acquisition program for monographs for the twelve resource libraries in Region IX of the Regional Medical Library Network is described. Each of the participating libraries has agreed to purchase all books of an assigned publisher which fall within a prescribed subject-format profile. It is hoped that this will help to reduce unnecessary duplication and contribute toward the development of resources in the region. 相似文献
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Jennifer R. Warren Michael L. Hecht David A. Wagstaff Elvira Elek Khadidiatou Ndiaye Patricia Dustman Flavio F. Marsiglia 《Journal of Applied Communication Research》2006,34(2):209-227
This study sought to determine if exposure to two communication-oriented activities, videotapes and public service announcements, accounts for changes in substance use among adolescents participating in the Drug Resistance Strategies Project's keepin' it REAL adolescent substance use prevention curriculum. Middle-school students (4,734, 72% Latino) responded to questionnaires related to these analyses. An analysis of covariance (ANCOVA) model was fit separately to six substance use outcomes. The results suggested that intervention students who saw four or five videos engaged in less substance use in the past month than did students who saw fewer videos. Having seen the PSAs one or more times did not predict the reported change in substance use. 相似文献
99.
The Dynamics of Opinion Formation in Local Popular Referendums: Why the Dutch Always Say No 总被引:1,自引:0,他引:1
There is growing research on voting behavior in referendums.However, the dynamics of opinion formation in popular referendums,referendums initiated by the electorate to approve or rejectdecisions made by representative bodies, has not yet been studied.This is especially unfortunate as voting decisions in popularreferendums differ from those in other referendums in interestingways. Opinion formation can be a very dynamic process in popularreferendums, making the referendum campaign crucial. This paperstudies the dynamics of opinion formation in popular referendumsand relates them to particular characteristics of the campaignsand the issues at hand. Based on the literature, we consideredthe effects of the intensity of the yes and no campaigns, familiaritywith the issue, and partisan cues. Our study uses content analysisdata and data from public opinion surveys dealing with variouspopular referendums held in the Netherlands. The study revealedseveral factors that contributed to the volatility of opinionsin the referendum campaigns: the issue (new and did not fittraditional political schemes), lack of support from societaland community organizations for the position of the local authorities,and low profile campaigns on the part of local authorities.While some of these factors are general and may play a rolein referendums everywhere, some can be considered typicallyDutch, related to the characteristics of popular referendumsin the Netherlands and the countrys political system. 相似文献
100.
Danuta A. Nitecki 《Archival Science》2004,4(1-2):17-44
Evaluators of library programs have different perspectives on why to conduct an evaluation and also how to do so. The author
suggests that a minimal approach to conducting a library program evaluation is to prove that the program exists. But this
perspective has expanded to include different degrees of interest in the client and operations, culminating in a combined
focus that leads evaluators to conduct outcome assessments. The chapter includes speculation on what motivates managers to
undertake an evaluation, a review of some ways that library evaluations are conducted, and a discussion of several examples
of program evaluations. Though there are not single directives for undertaking a library program evaluation, there are a variety
of tools and advice to entice librarians to do more of them as a way to improve understanding the value of a library to its
clientele and in society. 相似文献