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101.
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Structural equation models are increasingly used for clustered or multilevel data in cases where mixed regression is too inflexible. However, when there are many levels of nesting, these models can become difficult to estimate. We introduce a novel evaluation strategy, Rampart, that applies an orthogonal rotation to the parts of a model that conform to commonly met requirements. This rotation dramatically simplifies fit evaluation in a way that becomes more potent as the size of the data set increases. We validate and evaluate the implementation using a 3-level latent regression simulation study. Then we analyze data from a statewide child behavioral health measure administered by the Oklahoma Department of Human Services. We demonstrate the efficiency of Rampart compared to other similar software using a latent factor model with a 5-level decomposition of latent variance. Rampart is implemented in OpenMx, a free and open source software package.  相似文献   
103.
ABSTRACT

Successful sprinting depends on covering a specific distance in the shortest time possible. Although external forces are key to sprinting, less consideration is given to the duration of force application, which influences the impulse generated. This study explored relationships between sprint performance measures and external kinetic and kinematic performance indicators. Data were collected from the initial acceleration, transition and maximal velocity phases of a sprint. Relationships were analysed between sprint performance measures and kinetic and kinematic variables. A commonality regression analysis was used to explore how independent variables contributed to multiple-regression models for the sprint phases. Propulsive forces play a key role in sprint performance during the initial acceleration (r = 0.95 ± 0.03) and transition phases (r = 0.74 ± 0.19), while braking duration plays an important role during the transition phase (r = ?0.72 ± 0.20). Contact time, vertical force and peak propulsive forces represented key determinants (r = ?0.64 ± 0.31, r = 0.57 ± 0.35 and r = 0.66 ± 0.30, respectively) of maximal velocity phase performance, with peak propulsive force providing the largest unique contribution to the regression model for step velocity. These results clarified the role of force and time variables on sprinting performance.  相似文献   
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Journalists are frequently reporting about new and innovative products in news articles. Oftentimes, journalists use specific company and product information provided by enterprises that highlight a corporation’s social responsibility (CSR) activities. Based on framing theory and theory of reasoned action, an experiment was conducted to examine how types of CSR-framed news (either highlighting ethical, ecological, or philanthropic responsibilities of a company) affect news recipients’ product purchasing intentions. A mediation analysis showed that CSR-framed news indirectly and positively affected individuals’ purchasing intentions via company and product attitudes. No relevant differences could be detected for the specific type of CSR frame. Implications of the results are discussed.  相似文献   
106.
The definition of a problem and the action taken to solve it largely depend on the view which the individuals or groups that discovered the problem have of the system to which it refers. A problem may thus find itself defined as a badly interpreted output, or as a faulty output of a faulty output device, or as a faulty output due to a malfunction in an otherwise faultless system, or as a correct but undesired output from a faultless and thus undesirable system. All definitions but the last suggest corrective action; only the last definition suggests change, and so presents an unsolvable problem to anyone opposed to change (Herbert Brün, 1971).This article is an adaptation of an address given on March 29, 1971, at the opening of the Twenty-fourth Annual Conference on World Affairs at the University of Colorado, Boulder, Colorado, U.S.A.  相似文献   
107.
ABSTRACT

Community-based school governance has been promoted as a popular policy for decentralisation of education around the world. Within this policy, schools are expected to create institutional spaces such as School Management Committees with an assumption of reciprocal relation between school and community. This article questions the simplistic assumption through an ethnographic study of community-school relationship in Nepal. While these relationships may conflict with the kind of reciprocity assumed in school governance policies, we argue that this disjunctured reciprocity, firstly, reflects the gap between policy blueprints and action, and, secondly, reveals the competing logics of community-school relations which remain unacknowledged.  相似文献   
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109.
Beck  Valentin 《Metascience》2022,31(2):289-292
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110.
A bottlenose dolphin was trained to discriminate two simultaneously presented stimuli differing in numerosity (defined by the number of constituent elements). After responding correctly to stimuli consisting of three-dimensional objects, the dolphin transferred to two-dimensional stimuli. Initially, a variety of stimulus parameters covaried with the numerosity feature. By systematically controlling for these stimulus parameters, it was demonstrated that some of these attributes, such as element configuration and overall brightness, affected the animal’s discrimination performance. However, after all the confounding parameters were under control, the dolphin was able to discriminate the stimuli exclusively on the basis of the numerosity feature. The animal then achieved a successful transfer to novel numerosities, both intervening numerosities and numerosities outside the former range. These findings provide substantial evidence that the dolphin could base his behavior on the numerosity of a set independently of its other attributes and that he represented ordinal relations among numerosities.  相似文献   
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