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Alan Feingold 《Structural equation modeling》2019,26(3):418-429
Multilevel and latent growth modeling analysis (GMA) is often used to compare independent groups in linear random slopes of outcomes over time, particularly in randomized controlled trials. The unstandardized coefficient for the effect of group on the slope from a linear GMA can be transformed into a model-estimated effect size for the group difference at the end of a study. Because effect sizes vary nonlinearly in quadratic GMA, the effect size at the end of a study using quadratic GMA cannot be derived from a single coefficient, and cannot be used to estimate effect sizes at intermediate time points with backward extrapolation. This article formulates equations and associated input commands in Mplus for time-varying effect sizes for quadratic GMA. Illustrative analyses that produced these time-varying effect sizes were presented, and a Monte Carlo study found that bias in the effect sizes and their confidence intervals was ignorable. 相似文献
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Four pigeons pecked for food reinforcement on variable interval 1-min schedules and on the variable-interval 1-min components of multiple, concurrent, and pseudoconcurrent schedules. The pseudoconcurrent schedule provided only one schedule of reinforcement; but, any reinforcer could be collected by responding on either of two keys. The rate of responding generated by the variable interval schedule was not greater than the rates of responding generated by the components of the complex schedules. But, the rate of reinforcement obtained from the variable interval schedule was greater than the rates of reinforcement obtained from the components of the multiple schedule. These results may contradict the equation proposed by Herrnstein (1970). The equation predicts that the rate of responding generated by a schedule of reinforcement will be greater when the schedule appears alone, than when it appears as one component of a complex schedule. 相似文献
995.
This paper reports the results of a study of teacher opinions about the features considered important in an ideal textbook.
A survey of Queensland high school teachers revealed that they favoured texts that focus on student cognition and which provide
useful features such as exercises and practical activities. Differences were found between the preferences of Queensland teachers
and the preferences of teachers reported in two American studies. The significance of these differences for writers and publishers
is discussed.
Specializations: communication and cognition in science.
Specializations: science education. 相似文献
996.
Rats were tested in a specially constructed radial-arm maze that eliminated access to extramaze visual cues and allowed any effects of intramaze cues to be controlled. Despite this, choice accuracy was controlled by the spatial location of previously visited arms. Part of this control was attributed to vestibular or kinesthetic cues. This conclusion was corroborated by the finding that when explicit visual cues were moved from their standard (trained) spatial locations to novel locations, control of spatial choices was completely disrupted. The latter finding indicates that cues intrinsic to the rat (kinesthetic or vestibular information) and cues extrinsic to the rat (visual stimuli) operate in an integrated fashion. 相似文献
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Steven F. Schomberg Darwin D. Hendel Caroline L. Bassett 《Innovative Higher Education》1983,7(2):95-104
This article describes one institution's use of the College Outcome Measures Project (COMP) in comparing outcomes for graduates of traditional and non-traditional programs. The study was designed to answer three questions concerning the use of COMP in evaluating traditional and non-traditional programs. Results obtained in a study of 96 University of Minnesota graduating seniors suggest greater potential usefulness in distinguishing among institutions than in comparing outcomes of programs within an institution. The authors conclude that as new approaches and instruments for measuring college outcomes become available, criteria for instrument selection need to be shared among individuals charged with conducting outcome studies. 相似文献
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ABSTRACT: Decades of research have provided evidence that food irradiation is a safe technology that can decrease the incidence of foodborne diseases; however, adoption of this technology has been slow. The purpose of our study was to qualitatively explore the effectiveness of various components of a professional development training on family and consumer sciences county extension educators' understanding of food irradiation. This training included presentations by experts in the field, a tour of a food irradiation research facility and a meat processing facility, group activities, and a computer simulation model. Data were collected using qualitative research methodology through in-depth interviews conducted after the training. Results indicated that those components that allowed participants to visualize food irradiation processes seemed most beneficial to their understanding. Based on these data, implications for practice are discussed. 相似文献