The predictive value of numerical magnitude comparison for individual differences in mathematics achievement

Although it has been proposed that the ability to compare numerical magnitudes is related to mathematics achievement, it is not clear whether this ability predicts individual differences in later mathematics achievement. The current study addressed this question in typically developing children by means of a longitudinal design that examined the relationship between a number comparison task assessed at the start of formal schooling (mean age = 6 years 4 months) and a general mathematics achievement test administered 1 year later. Our findings provide longitudinal evidence that the size of the individual’s distance effect, calculated on the basis of reaction times, was predictively related to mathematics achievement. Regression analyses showed that this association was independent of age, intellectual ability, and speed of number identification.     

Children’s mapping between symbolic and nonsymbolic representations of number

When children learn to count and acquire a symbolic system for representing numbers, they map these symbols onto a preexisting system involving approximate nonsymbolic representations of quantity. Little is known about this mapping process, how it develops, and its role in the performance of formal mathematics. Using a novel task to assess children’s mapping ability, we show that children can map in both directions between symbolic and nonsymbolic numerical representations and that this ability develops between 6 and 8 years of age. Moreover, we reveal that children’s mapping ability is related to their achievement on tests of school mathematics over and above the variance accounted for by standard symbolic and nonsymbolic numerical tasks. These findings support the proposal that underlying nonsymbolic representations play a role in children’s mathematical development.     

Classroom climate and students' goal preferences: a cross-cultural comparison

Goal preferences indicate intentions to achieve or avoid particular states. We examined whether Curacaoan and Dutch students differ in goal preferences related to school and whether goal preferences are associated with students' evaluation of the classroom climate. Measurement invariance of the instruments was also tested between samples. Participants attended vocational high schools in Curacao ( N = 276) or in the Netherlands ( N = 283). Both the classroom climate and goal preferences differed between the samples. In the Netherlands the preference for individuality, belongingness, and recognition was stronger, whereas in Curacao mastery, satisfaction, self-determination, and material gain were more frequently endorsed. The two variables were modestly correlated. Schools do have a globalizing effect on students' school experiences and hardly adapt to goal preferences. The latter seem to be affected by non-school related cultural factors.     

Thin-Ideal Media and Women’s Body Dissatisfaction: Prevention using Downward Social Comparisons on Non-Appearance Dimensions

Exposure to thin-ideal media has adverse effects on the body satisfaction of women with higher levels of body image disturbance. In a study involving 109 UCLA female undergraduates, we examined the effectiveness of an intervention that was based on downward social comparison theory and the selection of alternative comparison dimensions. All participants had higher levels of body dissatisfaction and viewed pictures of fashion models; the intervention group compared downward with the models on non-appearance dimensions in writing, whereas the control group described the models in writing. We hypothesized that the intervention group would experience more positive shifts in body and weight satisfaction, anxiety about appearance, and desire to lose weight than would the control group. The results supported our hypotheses.     

Group norms and excessive absenteeism: The role of peer referent others

Drawing from social identity and social influence theory, we propose that the absence-related norms of an individual’s work-based referent others will have a significant effect on the likelihood of excessive absence behavior. We then develop and test a model of the social mechanisms potentially underlying the relationship between referent absence norms and the likelihood of excessive absence behavior. Our findings indicate that referent group norms significantly explain excessive absence behavior, even when taking into account the absence norms associated with the formal organizational units within which these referent groups are often nested. They also indicate that permissive referent group norms are likely to have a greater impact on the probability of target excessive absence when the target has a more conformist disposition. Finally, post-hoc findings suggest that the more negative targets’ perceptions of the consequences of absenteeism, the more attenuated the impact of permissive group norms on excessive absence behavior.     

生殖器疱疹研究现状及诊疗过程中的伦理问题

生殖器疱疹是单纯疱疹病毒感染生殖器部位皮肤黏膜所引起的炎症性疾病,是常见的性传播性疾病之一.近年来,随着其在人群中的流行率的不断增高,在国内已成为一个令人关注的公共卫生问题.本文就其病原学、流行状况、传播和潜在的危险性作一概述,并分析了在其诊疗过程中的伦理问题及相关的对策.     

Learning of letter names follows similar principles across languages: Evidence from Hebrew

Letter names play an important role in early literacy. Previous studies of letter name learning have examined the Latin alphabet. The current study tested learners of Hebrew, comparing their patterns of performance and types of errors with those of English learners. We analyzed letter-naming data from 645 Israeli children who had not begun formal reading instruction: a younger group (mean age 5 years 2 months) and an older group (mean age 6 years 2 months). Children's errors often involved letters with similar shapes or letters adjacent to one another in the alphabet. Most Hebrew letter names are not very similar to one another phonologically, and there were fewer phonologically based confusions than in English. We found both general frequency effects and frequency effects that reflected the letters in individual children's names. On average, girls knew more letter names than did boys. The results suggest that letter name learning follows similar principles across languages.     

不同学习压力觉知水平高中生家庭生态之比较

考察了170名高一学生的学习压力觉知水平,结果显示,经常感到学习压力、偶尔感到学习压力和未感到学习压力学生的比例分别为22．9％、53．6％和23．5％,不同学习压力觉知水平的人数差异极其显著。MANOVA分析发现,不同学习压力觉知水平的高中生在父母教养方式、家庭环境和学生人格等家庭生态群上总体差异显著;通过多重比较,揭示了不同学习压力觉知水平学生的家庭生态具瘁维度差异及其特点。文章从生态系统观点对中学生学习压力觉知差异进行了探讨,提出从生态重构角度对中学生进行学习减压。     

Self-schema and social comparison explanations of body dissatisfaction: a laboratory investigation

The current study was an investigation of the self-schema and social comparison theories of body dissatisfaction. The social comparison manipulation consisted of exposure to one of three levels of comparison figure: upward, downward, or no comparison. Two different imagery exercises served to prime either a participants’ appearance self-schema, or a non-appearance schema. Participants completed state measures of body image and mood at pre- and posttest. Results indicated no significant interaction between priming and social comparison and no significant main effect for priming. However, there was a significant effect of social comparison, such that those in the downward comparison condition showed an increase in body satisfaction and positive mood. Results are discussed in the context of self-schema theory and social comparison, and suggestions are given for future research that might further shed light on these theoretical approaches for understanding body dissatisfaction.     

Self‐evaluation and social comparison amongst adolescents with learning difficulties

Two studies are presented which examine self‐evaluation in adolescents with learning difficulties and how these adolescents strategically protect their self‐concept through the use of social comparison. Study one involved 145 adolescents with learning difficulties and the same number of non‐disabled adolescents aged between 11 to 16 years. All adolescents completed Harter's ‘Self Perception Profile for Children’ (SPPC). No significant overall differences were found between the self‐evaluations of the adolescents with learning difficulties and non‐disabled adolescents. In addition, adolescents with learning difficulties strategically devalued less favourable comparison dimensions and valued more positive comparison attributes. Study two utilized a four condition between‐groups design with a sample of 68 adolescents with learning difficulties. All participants completed the SPPC, but the availability of a social comparison group was systematically varied between conditions. The self‐evaluations made by adolescents changed significantly when the social comparison group made available was altered. The findings are discussed with regard to their theoretical implications and in terms of inclusion policies for adolescents with learning difficulties. Copyright © 2001 John Wiley & Sons, Ltd.