Suchergebnisse

Dietary patterns in China have changed dramatically over the past few decades as the Internet has become rapidly available. Based on data from the China Health and Nutrition Survey (2006–2011), we use a two-way fixed effects model and an instrumental variable approach to determine the impact of Internet use on the dietary quality of rural residents. The results indicate that Internet use could significantly improve the dietary quality of Chinese rural residents, with an increase of about 10.4% in the China Food Pagoda Score (CFPS), mainly due to the increase in the dietary quality score for five food groups: fruits, meats, eggs, oil, and salt. We also found that Internet use significantly increased the consumption amounts of milk and its products (4 g), fruits (31 g), eggs (8 g), and vegetables (34 g), while also decreasing the intake of salts (2 g) and oil (6 g). A possible mechanism is that Internet use improves the dietary knowledge of rural residents, thus optimizing their dietary structure. Moreover, the effect of the Internet was greater among females and those who prepare food for a family. Rural residents without a college degree enjoyed more benefits. In summary, governments should further promote Internet penetration in rural areas for health purposes.

With data from the New Brunswick School Climate Study (N = 6,883 students from 147 schools), this study examined individual differences in and school effects on health outcomes of students. Results of hierarchical linear modeling showed that females reported experiencing more physical health problems, eating less healthy food, and doing fewer exercises than males. Students of high socioeconomic status (SES) reported eating more healthy food and doing more exercises than students of low SES. Native students reported experiencing more physical health problems and eating less healthy food than nonnative students. Students of single parents reported eating more healthy food and exercising more than students of both parents. Schools showed effects on health outcomes over and above the effects of students. Students in schools with high SES and positive disciplinary climate reported fewer physical and mental health problems. Students in large schools reported less healthy food intake and fewer physical exercises.

The purpose of this study was to examine differences in the rate at which males and females acquired mathematical skills during secondary grades and to determine the relationship between their rates of growth and student- arid school-level characteristics. Based on data from the Longitudinal Study of American Youth (LSAY), a three-level hierarchical linear model (HLM) indicated that males and females acquired mathematical skills at the same rate. The variation in scores among students increased over time, and students maintained their initial position in the distribution. This fan-spread phenomenon among students was more pronounced in basic skills and knowledge than in problem-solving. Schools were more homogeneous in female rate of growth than in male rate of growth. The variation in scores among schools enlarged over time, and schools maintained their initial position in the distribution. This fan-spread phenomenon among schools was more pronounced in basic skills and knowledge than in problem-solving. Policy implications and suggestions for future research are provided. ; Le but de cette recherche était d'étudier les différences dans le rythme auquel les adolescents et les adolescentes ont acquis des habiletés en mathématiques pendant leurs années au secondaire et d'établir le rapport entre leur taux de croissance et des caractéristiques liées aux individus d'une part et à l'école d'autre part. D'après les données du Longitudinal Study of American Youth (LSAY), un modèle linéaire à trois niveaux (HLM) a indiqué que les filles et les garçons acquéraient des habiletés en mathématiques au même rythme. La variation dans les résultats s'est accrue avec le temps et les élèves ont maintenu leur position relative dans la distribution. Ce phénomène d'éventail chez les élèves était plus prononcé pour les habiletés et les connaissances de base que pour la capacité de résolution de problèmes. Les écoles présentaient des profils plus homogènes pour le taux d'assimilation des habiletés chez les filles que chez les garçons. La variation dans les résultats par école s'est accrue avec les temps et les écoles ont maintenu leur position relative dans la distribution. Ce phénomène d'éventail parmi les écoles était plus prononcé pour les habiletés et les connaissances de base que pour la capacité de résolution de problèmes. On présente des implications en ce qui concerne la politique et des suggestions pour la recherche à l'avenir.

With an educational issue that has caught the attention of many countries in the world (study load), a population of 8th graders from a typical Chinese metropolitan city (40,536 from 118 schools), and an advanced statistical strategy (multilevel piecewise regression), we examined whether there was a turning point in terms of the effects of study load on science achievement. We did identify a turning point for each and every measure of study load. For weekday learning on science achievement, we identified a turning point of 22.50 hr for the effects of in-school learning, 7.50 hr for the effects of homework, and 12 hr for the effects of after-school learning. For weekend learning on science achievement, we identified a turning point of 1.50 hr for the effects of in-school learning, 5 hr for the effects of homework, and 1 hr for the effects of after-school learning. In each case, the difference in effects before and after the turning point was statistically significant, indicating that the effects of study load on science achievement were nonlinear. All of these turning points offered important implications for science education.