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161.
This paper takes account of skills heterogeneity among workers with a higher education degree and proposes a new measure to differentiate between real and apparent overeducation based on the level of cognitive skills actually achieved by the individuals. This proposal is applied to the study of the wage effects of overeducation in the Spanish labor market using data from PIAAC. The results suggest that between a quarter and a half of the graduate workers who appear to be overeducated in the Spanish labor market could be considered as being only apparently overeducated since they show a lower level of skills than that corresponding to their educational level or, alternatively, a level of cognitive skills which is commensurate with their job. Different returns are found for each group of overeducated individuals both when compared with adequately educated peers within a similar level of education (with greater wage penalties for apparently overeducated workers) and when the comparison is done with well-matched co-workers doing a similar job (with a wage premium for real overeducation but no significant returns for apparently overeducated workers). These different returns by skill levels beyond what overeducation measures implies that the market distinguishes between education and skills and that educational attainment per se does not perfectly align with acquired skills, meaning that traditional measures of overeducation would overstate the actual level of skills mismatch in the labor market.  相似文献   
162.
We investigate the relationship between economic freedom and international migration for the 1980–2010 period using a dataset on migration from 91 emerging countries to the 20 most attractive OECD destination countries. We find that more economic freedom at home discourages high-skilled migration, but not low-skilled migration. The negative association between economic freedom and high-skilled emigration also holds when we estimate (dynamic) panel models that allow for endogeneity in the economic freedom-migration nexus. In sum, our findings suggest that high-skilled migration is especially responsive to the economic incentives resulting from economic freedom.  相似文献   
163.
This study used data from Waves 1 (1987–1989) and 2 (1992–1994) of the National Survey of Families and Households in the United States and a series of regression models, some of which included individual-specific fixed effects, to estimate associations of particular types and levels of debt with adult depressive symptoms. Results suggest that household debt is positively associated with greater depressive symptoms. However, this association appears to be driven by short-term (unsecured) debt; we found little evidence of associations with depressive symptoms for mid- or long-term debt. The link between short-term debt and depressive symptoms persisted with alternative estimation strategies, including defining debt in absolute and relative terms. Furthermore, this association was particularly concentrated among 51–64 year-old adults, those with a high school education or less, and those who were not stably married throughout the observation period. These findings suggest that short-term debt may have an adverse influence on psychological wellbeing, particularly for those who are less educated, approaching retirement age, or unmarried.  相似文献   
164.

Industrialized areas represent a special group of urbanized areas, but sufficient attention has not been given to them concerning plant species richness and its importance for biodiversity conservation. These sites are considered the main drivers of biological invasions and biotic homogenization on a global scale, but the question of how and to what degree they contribute to biodiversity has yet to be raised. Data for 62 river ports (16 German, 26 Czech, 7 Hungarian, 4 Slovak, and 9 Austrian) on two important Central European waterways (the Elbe-Vltava and Danube waterways) were gathered for 40 years. In total, 1 240 plant species were found. Of these, 371 were classified as threatened and protected, nearly one third of the total number of species found in all of the studied Elbe, Vltava, and Danube ports. Significant differences in the proportion of threatened species in ports and cities were not found. More threatened species were found in the Danube ports than in the other ports, but their numbers fluctuated depending on the size of the port and the region (country). The results showed that the ports must be regarded as special types of species-rich industrial areas; thus, they should not be considered to be only sources of spreading invasive alien species. When planning port development, uniformity and vegetation management that is too intensive should be avoided. Extensively managed open areas and habitat diversity should be maintained.

  相似文献   
165.
Child sexual abuse is one of the main types of abuse still to be addressed within the field of education, yet the education system itself can serve as a primary tool for its prevention. A better understanding of teachers’ knowledge and beliefs about child sexual abuse will allow us to establish key starting points from which to utilize the system for prevention. Four hundred and fifty teachers participated in this study, completing a questionnaire regarding their knowledge and beliefs about child sexual abuse. The study revealed that over half the teachers, 65.3% (n = 294), had never received any type of training in child sexual abuse education and that the majority were not familiar with methods of identifying child sexual abuse, 90.7% (n = 279). Various mistaken beliefs were identified among the participating teachers, such as pathological profiles of abusers, that the vast majority of child sexual abuse implies violent behavior, and that there cannot be abusers the same age as the victim. These results indicate that knowledge deficiencies do exist about child sexual abuse among teachers and highlight the need for training in this field.  相似文献   
166.
We evaluate the effectiveness in empirical migration research of the respondent-driven sampling (RDS) and the quota sampling with regard to four criteria: quality of the data; sociometric diversity of the sample; geographic coverage of the sample; and cost-effectiveness. We review two surveys of ex-USSR migrants, conducted simultaneously in the Warsaw metropolitan area, each undertaken with the use of one of the two sampling methods. We find that although the RDS was considerably costlier, it enabled faster data collection and posed a lower risk of underestimating the cost of the survey. We also find that the RDS generated higher-quality data, and that it was more successful in surveying short-term circular migrants. This comparative evaluation contributes to the literature on social research methods in that it links the sampling methods with the quality and character of the data, and helps assess the usefulness and applicability of RDS in empirical migration studies.  相似文献   
167.
Urbanization affects the availability and diversity of floral resources (pollen and/or nectar) for wild pollinating insects. For example, urban green areas are characterized by an abundance of ornamental plant species. Increasingly, trees are planted to improve the aesthetics of urban streets and parks. These urban trees might offer important floral resources to pollinating insects. To examine the suitability of urban trees as resources for pollinating insects, we investigated the chemical composition of pollen and nectar as well as the amount of nectar produced by the nine major insect-pollinated tree species planted in cities of Western Europe, namely Acer pseudoplatanus, Aesculus carnea, A. hippocastanum, Robinia pseudoacacia, Tilia cordata, T. x euchlora, T. x europaea, T. platyphyllos and T. tomentosa. The analyses revealed that globally the Tilia trees provide pollen with lower contents of polypeptides, amino acids and phytosterols compared with the other species. Urban tree flowers offer abundant nectar with relatively high sugar contents (0.16–1.28 mg/flower); sucrose was the predominant sugar in all nectars. The investigated tree species could therefore be considered in future city plantings.  相似文献   
168.
We used a longitudinal community study of 674 grade school children (Grades 5, 6, 7, and 8; 337 males, 337 females) of Mexican origin to examine outcomes of school attachment. Attachment to school is important in this population given the high level of school dropout rates of Mexican‐origin students. Results indicated that, on average, school attachment from fifth to sixth grade remains stable, but declines from sixth to eighth grade. Boys had lower levels of school attachment at fifth grade but followed similar patterns of change as girls did. Attachment to teachers, peer competence, school aspirations and expectations, and substance‐use cognitions emerged as longitudinal outcomes of level or changes in school attachment. Gender moderated associations of school attachment.  相似文献   
169.
170.
The Organic Law on the Improvement of the National Education Quality (Ley Orgánica de Reforma de la Calidad Educativa) readdressed one of the most significant educational issues: educational policies related to immigrant students. Therefore, this is an appropriate moment to evaluate these types of policies in three singular Spanish regions: Madrid, Catalonia and Andalusia. This article presents an analysis of the measures taken in three Spanish regions: Madrid, Catalonia and Andalusia in response to students’ reception, acceptance and enrolment of immigrant students. A qualitative methodology based on the comparative method is used. Diverse similarities, but also specific characteristics and differences, can be found among the three models associated with each region. There are several significant differences that can be appreciated, such as the institutional role, as well as other specific measures. However, singular features are also identified, such as the diverse policies for the use of the vehicular language in each of the cases. Finally, the comparisons highlight various critical aspects, such as attention devoted to the students’ native language and progress towards intercultural education in school strategies and planning.  相似文献   
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