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Development of early math skill depends on a prerequisite level of cognitive development. Identification of specific cognitive skills that are important for math development may not only inform instructional approaches but also inform assessment approaches to identifying children with specific learning problems in math. This study investigated the specific cognitive correlates of math problem solving across early grade levels (1–4) while controlling for basic calculation skills. As expected, basic calculation skill was a significant predictor of math problem solving across the entire sample. However, the addition of cognitive measures almost doubled the variance explained (R2 = .61). Additionally, only select cognitive variables contributed to the prediction of math problem solving, and these variables change in importance as children develop higher‐level math skills. Results are discussed within a developmental model, which emphasizes the increasing importance of abstract code representations required in higher levels of math performance. 相似文献
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Ageing anxiety is the expression of peoples' fear of ageing (Lynch, 2000). Despite greater longevity in the population, there is a lack of research into this aspect of life (Lasher &; Faulkender, 1993). This research explored fears of ageing across four dimensions: Fear of Old People, Physical Appearance, Psychological Concerns, and Fear of Losses. Three hundred and forty eight participants aged 18–88 participated in an online survey. Findings were: (a) men and women have different fears of ageing; (b) greater quality contact is related to less ageing anxiety; (c) poor health is related to greater ageing anxiety, (d) ageism, defined by Nelson (2005) as prejudice toward ageing is positively correlated with ageing anxiety. The implications of these findings are that better quality contact and more positive attitudes toward ageing are associated with less ageing anxiety. As such, possible key target areas in developing appropriate interventions are provided, with hope to prepare adults of all ages for the inevitable—life is a terminal illness, so enjoy while you can. 相似文献
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Emily E. Scott Jack Cerchiara Jenny L. McFarland Mary Pat Wenderoth Jennifer H. Doherty 《科学教学研究杂志》2023,60(1):63-99
In recent years, there has been a strong push to transform STEM education at K-12 and collegiate levels to help students learn to think like scientists. One aspect of this transformation involves redesigning instruction and curricula around fundamental scientific ideas that serve as conceptual scaffolds students can use to build cohesive knowledge structures. In this study, we investigated how students use mass balance reasoning as a conceptual scaffold to gain a deeper understanding of how matter moves through biological systems. Our aim was to lay the groundwork for a mass balance learning progression in physiology. We drew on a general models framework from biology and a covariational reasoning framework from math education to interpret students' mass balance ideas. We used a constant comparative method to identify students' reasoning patterns from 73 interviews conducted with undergraduate biology students. We helped validate the reasoning patterns identified with >8000 written responses collected from students at multiple institutions. From our analyses, we identified two related progress variables that describe key elements of students' performances: the first describes how students identify and use matter flows in biology phenomena; the second characterizes how students use net rate-of-change to predict how matter accumulates in, or disperses from, a compartment. We also present a case study of how we used our emerging mass balance learning progression to inform instructional practices to support students' mass balance reasoning. Our progress variables describe one way students engage in three dimensional learning by showing how student performances associated with the practice of mathematical thinking reveal their understanding of the core concept of matter flows as governed by the crosscutting concept of matter conservation. Though our work is situated in physiology, it extends previous work in climate change education and is applicable to other scientific fields, such as physics, engineering, and geochemistry. 相似文献
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Rich Ling Johannes Bjelland Pål Roe Sundsøy Scott W. Campbell 《The Information Society》2014,30(4):282-291
This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal and spatial movement is highly predictable and that the majority of calls and text messages are sent to only four to six different persons. This article extends this research by examining both tie strength and the distance between the interlocutors in urban and rural settings. The findings show that even as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius. 相似文献
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Frederick W. Derrick Nancy A. Williams Charles E. Scott 《Journal of Cultural Economics》2014,38(2):173-189
This paper advances the ongoing discussion of methods for predicting movie box office revenues with two contributions to the methodology and an out-of-sample test of the model. The first innovation is the development of a two-stage model using publicly available pre-release indicators to predict (1) initial week and (2) subsequent run box office revenues. To incorporate the experience-good nature of movies, the second stage is estimated by incorporating a proxy variable for box office success during the first week relative to predicted first week success. The second contribution is an empirical test of De Vany and Walls’ (J Econ Dyn Control 28:1035–1057, 2004) finding that the distribution of movie revenues has “heavy tails” and follows a non-Gaussian stable distribution with infinite variance. We estimate the two-stage model of a movie’s box office success on all general release movies in 1 year with both the Gaussian and stable distribution with heavy tails and infinite variance and find no evidence for the stable distribution in either stage of the estimation. This two-stage model is validated by comparing all general release movies in 3 future years (out-of-sample data) to the model’s predictions. 相似文献
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