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831.
Laura M. Argys Daniel I. Rees Dominic J. Brewer 《Journal of policy analysis and management》1996,15(4):623-645
Schools across the country are ending the practice of grouping students based on ability, in part, because of research indicating that tracking hurts low-ability students without helping students of other ability levels. Using a nationally representative survey conducted by the National Center for Education Statistics, (NCES) we reexamine the impact of tracking on high school student achievement through the estimation of a standard education production function. This approach allows us to control for the possibility that track is correlated with factors such as class size and teacher education. In addition, we address the possibility that there are unobserved student or school characteristics that affect both achievement and track placement. Our results indicate that abolishing tracking in America's schools would have a large positive impact on achievement for students currently in the lower tracks, but that this increase in achievement would come at the expense of students in upper-track classes. 相似文献
832.
Jarman Hannah K. Marques Mathew D. McLean Siân A. Slater Amy Paxton Susan J. 《Journal of youth and adolescence》2021,50(12):2279-2293
Journal of Youth and Adolescence - Adolescents are spending considerable time on social media, yet it is unclear whether motivations for social media use drive different forms of social media... 相似文献
833.
834.
In this study we examined the role of psychological buffers (life satisfaction, self-esteem, perception of family cohesion, and perception of social support) in the development of hopelessness and suicidal ideation. The participants were 314 university students, 71 males and 243 females, who were asked to complete a battery of instruments measuring the psychological buffers mentioned above. The results of a set of hierarchical multiple regression analyses suggested that life satisfaction and self-esteem are independent predictors of lower levels of hopelessness, while perception of social support seems to be the major predictor of lower levels of suicidal ideation independent of depression and hopelessness severity. Thus, hopelessness seems to be minimized by the level of life satisfaction and level of self-esteem exhibited by the individuals, while the key factor to the mitigation of suicidal ideas seems to be perception of social support. 相似文献
835.
Hamideh P. Ramjerdi 《Asia Europe Journal》2007,5(2):253-265
Solow’s Growth Model Solow (Q J Econ 70:65–94, 1956) and aggregate data are applied to estimates the increase in productivity due international trade and the
resulting technical change and capital augmentation for the years 1970 to 1978 and 1978 (the beginning of the reforms and
“open door” policy in China) to 1993. According this paper’s estimations the GDP per man hour in 1978 increased by 1.76 times
for the year 1970, from $0.1233 in 1970 to $0.2169 in 1978, and in 1993 by 5.23 time that of 1978 to $1.1348 in 1993. For
the period under study due to “open door” policy the GDP per man-hour more than quadrupled, and 76.18% of this increase was
due to technical changes and the remaining 23.82 was due to capital augmentation. The paper consists of five sections. “Introduction”
Section reviews some of the growth literature as well as looking at the macroeconomic measures of China’s economic performance
since 1978 the beginning of the reforms. “Data” Section explains the data modifications. “Empirical results” Section portrays
the empirical results and the next indicates conclusions.
This paper is dedicated to the memories of Late Dr. Anthony D’Amato, who was a Professor at W. Paul Stillman School of Business
at Seton Hall University South Orange, New Jersey.
相似文献
Hamideh P. RamjerdiEmail: |
836.
高等教育创新的新机遇 总被引:1,自引:0,他引:1
刘遵义 《国家教育行政学院学报》2006,(9):20-23
人口结构的变化、科学技术的变革以及经济全球化,都对高等教育产生了很大影响,提供了很多新的机遇。这些机遇不仅可以提高我们的效率,同时也可以带来新的创造知识和传播知识的方式方法。 相似文献
837.
Mastrotheodoros Stefanos Van der Graaff Jolien Deković Maja Meeus Wim H. J. Branje Susan 《Journal of youth and adolescence》2020,49(1):119-135
Journal of Youth and Adolescence - Parent–adolescent conflict can be intense, yet parents and adolescents do not always agree on the intensity of conflict. Conflict intensity tends to change... 相似文献
838.
Sierra F. Kaszubinski B.Sc. Jennifer L. Pechal Ph.D. Carl J. Schmidt M.D. Heather R. Jordan Ph.D. Mark E. Benbow Ph.D. Mariah H. Meek Ph.D. 《Journal of forensic sciences》2020,65(2):513-525
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications. 相似文献
839.
Kevin J. Farrugia Ph.D. Danielle Hunter B.Sc. Clarice Wilson B.Sc. Stef Hay B.Sc. Paul Sherriffs B.Sc. Paul Deacon B.Sc. 《Journal of forensic sciences》2020,65(1):248-254
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks. 相似文献
840.