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431.
Clusters,convergence, and economic performance   总被引:1,自引:0,他引:1  
This paper evaluates the role of regional cluster composition in regional industry performance. On the one hand, diminishing returns to specialization in a location can result in a convergence effect: the growth rate of an industry within a region may be declining in the level of economic activity of that industry. At the same time, positive spillovers across complementary economic activities can provide an impetus for agglomeration: the growth rate of an industry within a region may be increasing in the “strength” (i.e., relative presence) of related industries. Building on Porter (1998, 2003), we develop a systematic empirical framework to analyze the role of regional clusters – groups of closely related industries operating within a particular region – in the growth of regional industries. We exploit data from the US Cluster Mapping Project to examine the effects of agglomeration within regional clusters after controlling for convergence at the region-industry level. Our findings suggest that industries located in a strong cluster register higher employment and patenting growth. Regional industry growth also increases with the strength of related clusters in the region and with the strength of similar clusters in adjacent regions. We also find evidence of the complementarity between employment and innovation performance in regional clusters: both the initial employment and patenting strength of a cluster have a separate positive effect on the employment and patenting growth of the constituent industries. Finally, we find that new regional industries emerge where there is a strong cluster. These findings are consistent with multiple types of externalities arising in clusters, including knowledge, skills, and input–output linkages.  相似文献   
432.
Although often conceptualized in contradictory terms, the common assumption that natural and supernatural explanations are incompatible is psychologically inaccurate. Instead, there is considerable evidence that the same individuals use both natural and supernatural explanations to interpret the very same events and that there are multiple ways in which both kinds of explanations coexist in individual minds. Converging developmental research from diverse cultural contexts in 3 areas of biological thought (i.e., the origin of species, illness, and death) is reviewed to support this claim. Contrary to traditional accounts of cognitive development, new evidence indicates that supernatural explanations often increase rather than decrease with age and supports the proposal that reasoning about supernatural phenomena is an integral and enduring aspect of human cognition.  相似文献   
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Attachment was examined as a predictor of teens’ empathic support for friends in a multimethod longitudinal study of 184 U.S. adolescents (58% Caucasian, 29% African American, 13% other) followed from ages 14 to 18. Adolescents’ secure state of mind regarding attachment at 14 predicted teens’ greater capacity to provide empathic support during observed interactions with friends across ages 16–18 (Baverage = .39). Teens’ empathic support was generally stable during this period, and less secure teens were slower to develop these skills. Further, teens’ attachment security predicted the degree to which friends called for their support (Baverage = .29), which was associated with teens’ responsiveness to such calls. The findings suggest that secure attachment predicts teens’ ability to provide empathic support in close friendships.  相似文献   
436.
There is widespread agreement that early intervention for children with visual impairments and their families is important and beneficial. However, few con- trolled prospective studies of the effectiveness of various types of early intervention have been completed with these children. This randomized study evaluated the immediate and long-term effects of a comprehensive, weekly homebased intervention for infants and toddlers with visual impairments, compared with a low-intensity treatment through parent group meetings offered approximately 12 times per year. In annual assessments conducted for t h e years after the intervention was begun, there were negligible statistically significant or practical differences between groups based on a variety of measures of child and family functioning. In light of the cost-effectiveness analyses reported, questions are raised about the type of early intervention that should be provided to children with visual impairments.  相似文献   
437.
We explore the effect of bullying at school on the educational attainment of a sample of individuals drawn from the British National Child Development Study (NCDS). Our empirical findings suggest that school bullying has an adverse effect on human capital accumulation both at and beyond school. Moreover; the impact of bullying on educational attainment at age 16 is found to be similar in magnitude to class size effects. Furthermore, in contrast to class size effects, the adverse influence of bullying on educational attainment remains during adulthood. In addition, being bullied at school influences wages received during adulthood as well as indirectly influencing wages via educational attainment.  相似文献   
438.
Adolescent success providing satisfying support in response to a close friend's call in a caregiving task was examined as a potentially fundamental developmental competence likely to predict future social functioning, adult caregiving security, and physical health. Adolescents (86 males, 98 females; 58% White, 29% African American, 8% mixed race/ethnicity, 5% other) were followed from ages 13 to 33 (1998–2021) using multiple methods and reporters. Early caregiving success was found to predict greater self- and partner-reported caregiving security, lower negativity in adult relationships, and higher adult vagal tone. Results are interpreted as advancing our understanding beyond simply recognizing that adolescent friendships have long-term import, to now identifying specific capacities within friendships that are linked to longer-term outcomes.  相似文献   
439.
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