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121.
An important concern when planning research studies is to obtain maximum precision of an estimate of a treatment effect given a budget constraint. When research designs have a multilevel or hierarchical structure changes in sample size at different levels of the design will impact precision differently. Furthermore, there will typically be differential costs of enrolling additional units at different levels of the hierarchy. The optimal design problem in multilevel research studies involves determining the optimal sample size at each level of the design given specified design parameters and a specified marginal cost of recruitment at each level. The current work extends existing results by considering optimal design for (a) unbalanced random assignment designs and (b) regression discontinuity designs. 相似文献
122.
We studied individual differences in 3-month-olds' perceptions of smiling and the experiential correlates of those differences. In the laboratory, infants saw a graduated series of smiles that grew in intensity of expression. As a group, 3-month-olds preferred increasingly intense expressions of smiling, but individually they showed different growth rates of preference across the smiling series. Further, infants' preferences related to their home experiences: Infants who showed greater sensitivity to smiling had mothers who more frequently encouraged attention to themselves when they were smiling and their infants were looking at them. Infant discrimination within and between categories of facial expression and the relative strengths of association between different kinds of naturally occurring experiences and infant perceptual sensitivity are discussed. 相似文献
123.
This study determined if test rats could utilize biological odors, generated from donor rats receiving reward (R) and frustrative nonreward (N) treatments, to predict reward and nonreward goal events equally well. In Phase 1, two groups of test rats were exposed to R and N odors that signaled, respectively, either R and N goal events (“same” condition) or N and R goal events (“opposite” condition). Rats demonstrated significant discriminative use of these odors under both conditions. Subjects in the “opposite” condition, however, were slightly slower to learn the discrimination. Reversal learning was readily accomplished in Phase 2, regardless of the same-opposite factor. Thus, little evidence for a constraint on learning was found, and an interpretation in terms of interfering response tendencies and their habituation seemed favored. 相似文献
124.
T H Bryan 《Journal of learning disabilities》1978,11(2):107-115
125.
H. Carl Haywood Anthony L. Brown 《European Journal of Psychology of Education - EJPE》1990,5(2):243-252
Even though behavior management is a very high priority of teachers of young children, systems of behavior management receive less attention than do methods of teaching academic content. Even when there are well developed sytems of behavior management, they do not necessarily reflect the same philosophy and methods of teaching that are used to teach content. The authors report on “cognitive-mediational behavior management”, a system designed to be consistent with a cognitive early education program, the Cognitive Curriculum for Young Children. In both behavior management and all their other teaching, teachers use in this program a mediational teaching style. Teachers emphasize thinking processes rather than correct answers, take a problem-solving approach to learning, help children to acquire generalizable strategies of thinking and problem-solving rather than using trial-and-error learning, are optimistic about children’s abilities to learn, and facilitate children’s acquisition of fundamental thinking modes. This system is seen as basically incompatible with a behaviorist, contingent reinforcement system. Behavior sequences are suggested for working with unacceptable behavior so as to produce both behavior change and cognitive change. 相似文献
126.
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128.
We investigated differences between field-study classrooms and traditional science classrooms in terms of the learning environment and students’ attitudes to science, as well as the differential effectiveness of field-study classrooms for students differing in sex and English proficiency. A modified version of selected scales from the What Is Happening In this Class? questionnaire was used to assess the learning environment, whereas students’ attitudes were assessed with a shortened version of a scale from the Test of Science Related Attitudes. A sample of 765 grade 5 students from 17 schools responded to the learning environment and attitude scales in terms of both their traditional science classrooms and classrooms at a field-study centre in Florida. Large effect sizes supported the effectiveness of the field-studies classroom in terms of both the learning environment and student attitudes. Relative to the home school science class, the field-study class was considerably more effective for students with limited English proficiency than for native English speakers. 相似文献
129.
Haim?EshachEmail author Michael?N.?Fried 《Journal of Science Education and Technology》2005,14(3):315-336
This essay considers the question of why we should teach science to K-2. After initial consideration of two traditional reasons for studying science, six assertions supporting the idea that even small children should be exposed to science are given. These are, in order: (1) Children naturally enjoy observing and thinking about nature. (2) Exposing students to science develops positive attitudes towards science. (3) Early exposure to scientific phenomena leads to better understanding of the scientific concepts studied later in a formal way. (4) The use of scientifically informed language at an early age influences the eventual development of scientific concepts. (5) Children can understand scientific concepts and reason scientifically. (6) Science is an efficient means for developing scientific thinking. Concrete illustrations of some of the ideas discussed in this essay, particularly, how language and prior knowledge may influence the development of scientific concepts, are then provided. The essay concludes by emphasizing that there is a window of opportunity that educators should exploit by presenting science as part of the curriculum in both kindergarten and the first years of primary school. 相似文献
130.
In order to attempt to assess aspects of clinical competence, not adequately assessed by other means, the Center for the Study of Medical Education, University of Illinois College of Medicine together with the American Board of Orthopaedic Surgery developed oral examinations in formats specifically designed to yield information on high level cognitive functioning. The examinations were administered to 784 candidates for certification in January 1968. Reliability of the oral problem-solving component score pooled from four examiners was approximately .50. Assessment of content, construct, and concurrent validity made by questionnaire and factor analytic studies indicated that the oral tests identified factors not measured by multiple-choice tests and, therefore, significantly improved the relationship between supervisory evaluations and test scores. 相似文献