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951.
Previous research has established that SAT scores and high school grade point average (HSGPA) differ in their predictive power and in the size of mean differences across racial/ethnic groups. However, the SAT is scaled nationally across all test takers while HSGPA is scaled locally within a school. In this study, the researchers propose that this difference in how SAT scores and HSGPA are scaled partially explains differences in validity and subgroup differences. Using a large data set consisting of 170,390 students each of whom matriculated at one of 114 separate colleges, the researchers find that awarding SAT scores by ranking SAT within a high school generally results in substantial reduction in the size of subgroup mean differences for this predictor. However, validity for predicting first‐year GPA is also reduced by a small amount. Conversely, placing HSGPA onto a nationally normed metric through the use of multiple regression procedures results in a moderate increase in the size of subgroup mean differences, while also producing a small increase in validity. Taken together, these findings suggest that differences in predictor scaling can partially explain differences in the size of subgroup mean differences between HSGPA and SAT scores and have implications for predictive power.  相似文献   
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Abstract

Four sprint starting positions—the bunch, medium, elongated, and hyperextended—were compared on mean elapsed times at distances of 10 and 30 yd. Averages of three starts for each of 30 inexperienced college undergraduate males on each type of start were derived from electronically-controlled measures, the times for both distances being recorded from the same start. Statistical analyses indicated significantly lower elapsed times with the hyperextended starting position.  相似文献   
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Aging and its effects on a person's quality of life are a growing health concern and burden for many Americans. Recently, studies have shown that adopting certain healthy behaviors may help maintain and or prevent age-related health issues such as cognitive decline. However, many people are unaware of these newfound facts. Furthermore, there is insufficient research evidence to understand how older adults view brain health and the differences between diverse groups of older adults. This study examines brain health knowledge and behaviors among Caucasian and African-American community-dwelling older adults in North Carolina. Findings were significant for level of education and total brain health knowledge scores, though there were no significant differences between races. In addition, there was a significant association between total number of health conditions and total brain health knowledge scores that warrants further study.  相似文献   
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In an effort to establish a baseline of technology competency among our entering education students, our College of Education began implementing the Assessment of Technology Competencies (ATC) in Fall 2003. This performance-based assessment evaluates word-processing, presentation, spreadsheet, graphic/drawing, and Internet skills. Although students are not required to pass the ATC, failure impacts their final grade in an Introduction to Education course. This paper explores the impact this assessment has had on the students' use and development of technology in subsequent courses. Student perceptions of the ATC and its impact were elicited through a self-reported survey administered in a junior-level education course. Results indicate that the ATC has facilitated technology use among the participants. Respondents also revealed that their high school experiences with technology adequately prepared them for passing the ATC, despite the fact that most students are unable to pass the ATC in the first attempt.  相似文献   
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Dawn of science     
T. Padmanabhan 《Resonance》2012,17(6):532-537
With the works of Cavendish, Priestley and Lavoisier, chemistry emerged as an exact science.  相似文献   
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