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111.
社会因素对剖宫产率的影响 总被引:16,自引:0,他引:16
近二三十年来,剖宫产率在世界范围内不断升高。究其原因,除了医学因素外,社会因素起着重要作用,从社会经济发展,社会科学文化水平、社会习俗观念、法律、医疗道德、国家计划生育政策、医学教育等多个角度分析了社会因素对剖宫产率的影响,并就如何发挥社会因素的积极作用,消除和避免其消极作用,使剖部率维持在合理的范围内进行了讨论。 相似文献
112.
多层线性模型在纵向研究中的运用 总被引:13,自引:0,他引:13
纵向研究中传统统计技术主要是重复测量的方差分析和多元回归分析,但是这两种技术存在一些局限性,不能合理而充分地解释纵向研究资料。近年来出现的多层线性模型能够更有效地利用纵向数据。为促进多层线性模型在纵向研究中的运用,简要论述了传统统计技术的局限,介绍了多层线性模型的原理及其在纵向研究中的作用,以一组模拟数据为例对多层线性模型中各种参数在纵向研究中的含义进行了详细讨论,对于纵向研究中运用多层线性模型时须注意的问题提出了建议。 相似文献
113.
Representation and working memory in early arithmetic 总被引:1,自引:0,他引:1
Working memory has been implicated in the early acquisition of arithmetic skill, but the relations among different components of working memory, performance on different types of arithmetic problems, and development have not been explored. Preschool and Grade 1 children completed measures of phonological, visual-spatial, and central executive working memory, as well as nonverbal and verbal arithmetic problems, some of which included irrelevant information. For preschool children, accuracy was higher on nonverbal problems than on verbal problems, and the best and only unique predictor of performance on the standard nonverbal problems was visual-spatial working memory. This finding is consistent with the view that most preschoolers use a mental model for arithmetic that requires visual-spatial working memory. For Grade 1 children, performance was equivalent on nonverbal and verbal problems, and phonological working memory was the best predictor of performance on standard verbal problems. For both age groups, problems with added irrelevant information were substantially more difficult than standard problems, and in some cases measures of the central executive predicted performance. Assessing performance on different components of working memory in conjunction with different types of arithmetic problems provided new insights into the developing relations between working memory and how children do arithmetic. 相似文献
114.
A review of the debate on the Empirically Supported Treatment Program is presented. It is argued that underlying the specifics of the debate are fundamentally incompatible paradigms: a meaning vs. a medical model. The findings from two gold standard multi-site studies are reviewed to conclude that the control condition meets requirements for an empirically supported treatment. The empirical finding of the failure of clinical training to improve treatment outcomes is explained by the focus on rational factors in training. It is recommended that training of therapists focus on enhancing experiential capacity rather than mastery of manualized treatment approaches. 相似文献
115.
A necessary and sufficient condition is given in this paper for the existence and uniqueness of the maximum likelihood (the
so-called joint maximum likelihood) estimate of the parameters of the Partial Credit Model. This condition is stated in terms
of a structural property of the pattern of the data matrix that can be easily verified on the basis of a simple iterative
procedure. The result is proved by using an argument of Haberman (1977).
The author wishes to thank the Editor and the anonymous reviewers for their comments that helped to substantially improve
the final version of this paper.
This research was supported in part by a MURST grant (ex 60%). 相似文献
116.
Two new tests for a model for the response times on pure speed tests by Rasch (1960) are proposed. The model is based on the
assumption that the test response times are approximately gamma distributed, with known index parameters and unknown rate
parameters. The rate parameters are decomposed in a subject ability parameter and a test difficulty parameter. By treating
the ability as a gamma distributed random variable, maximum marginal likelihood (MML) estimators for the test difficulty parameters
and the parameters of the ability distribution are easily derived. Also the model tests proposed here pertain to the framework
of MML. Two tests or modification indices are proposed. The first one is focused on the assumption of local stochastic independence,
the second one on the assumption of the test characteristic functions. The tests are based on Lagrange multiplier statistics,
and can therefore be computed using the parameter estimates under the null model. Therefore, model violations for all items
and pairs of items can be assessed as a by-product of one single estimation run. Power studies and applications to real data
are included as numerical examples. 相似文献
117.
Quantitative psychology is concerned with the development and application of mathematical models in the behavioral sciences.
Over time, models have become more complex, a consequence of the increasing complexity of research designs and experimental
data, which is also a consequence of the utility of mathematical models in the science. As models have become more elaborate,
the problems of estimating them have become increasingly challenging. This paper gives an introduction to a computing tool
called automatic differentiation that is useful in calculating derivatives needed to estimate a model. As its name implies,
automatic differentiation works in a routine way to produce derivatives accurately and quickly. Because so many features of
model development require derivatives, the method has considerable potential in psychometric work. This paper reviews several
examples to demonstrate how the methodology can be applied.
From the Presidential Address delivered at the 70th Annual Meeting of the Psychometric Society, Tilburg University, The Netherlands,
July 5–8, 2005. 相似文献
118.
Lynam DR Caspi A Moffitt TE Raine A Loeber R Stouthamer-Loeber M 《Journal of abnormal child psychology》2005,33(4):431-443
The present study examines the relation between psychopathy and the Big Five dimensions of personality in two samples of adolescents. Specifically, the study tests the hypothesis that the aspect of psychopathy representing selfishness, callousness, and interpersonal manipulation (Factor 1) is most strongly associated with low Agreeableness, whereas the aspect of psychopathy representing impulsivity, instability, and social deviance (Factor 2) is associated with low Agreeableness, low Conscientiousness, and high Neuroticism. Data from 13- and 16-year-old boys and their mothers from two samples of the Pittsburgh Youth Study are used to test these hypotheses. Results were consistent across age and rating source in supporting the initial hypotheses, providing support for the construct of juvenile psychopathy and the interpretation of psychopathy as a constellation of traits drawn from a general model of personality functioning. 相似文献
119.
Barry?A.?HongEmail author Gerald?Leventhal Richard?J.?Seime 《Journal of clinical psychology in medical settings》2005,12(3):247-256
This paper highlights the role of the Association of Medical School Psychologists (AMSP) as a bridge between academic medicine and psychology. AMSP’s affiliation with Division 12 of the American Psychological Association is discussed, but the primary focus is AMSP’s affiliation with the Association of American Medical Colleges (AAMC) and the AAMC’s Council of Academic Societies (CAS). The history, structure, activities, and goals of AAMC and CAS are examined. AMSP’s affiliation with AAMC is important for psychologists in medical schools and academic medical centers, and for psychology in general, because AAMC is the major voice of academic medicine in the US. AAMC activities affect medical education at all levels, as well as research and health services at academic medical centers, and health care policy at the national level. AMSP’s dual affiliation with AAMC’s CAS and APA’s Society of Clinical Psychology will increase psychology’s visibility and influence in academic medical centers and enhance the two-way flow of ideas and information between academic medicine and psychology. 相似文献
120.