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11.
We investigated the development of the other‐race effect “ORE” in a longitudinal sample of 3‐, 6‐, and 9‐month‐old Caucasian infants. Previous research using cross‐sectional samples has shown an unstable ORE at 3 months, an increase at 6 months and full development at 9 months. In Experiment 1, we tested whether 9‐month‐olds showed the ORE with Caucasian and African faces. As expected, the 9‐month‐olds discriminated faces within their own ethnicity (Caucasian) but not within the unfamiliar ethnicity (African). In months. In Experiment 2, we longitudinally tested infants at 3, 6, and 9 months by presenting either the Caucasian or the African faces used in Experiment 1. In contrast to previous cross‐sectional studies and Experiment 1, we found that infants discriminated between all stimuli. Hence, we did not find the ORE in this longitudinal study even at 9 months. We assume that the infants in our longitudinal study showed no ORE because of previous repetitive exposure to African faces at 3 and 6 months. We argue that only a few presentations of faces from other ethnic categories sufficiently slow the development of the ORE.  相似文献   
12.
The civil war in Burundi (1993–2005) led to the forced displacement of a large part of the population. This study aims to explore how that displacement affected fertility behavior. Using a nationally representative, retrospective survey on birth and residential histories of 4,523 Burundian women, we examine the impact of conflict-induced displacement on fertility. These unique data enable us to distinguish between remaining-in-place, voluntary migration, and forced displacement, as well as to distinguish between periods spent “on the move” versus periods spent in residence in the new site. Adopting a semiparametric regression model, we analyze both the probability of the first pregnancy and the subsequent spacing of higher order pregnancies. We find that the risk of a first pregnancy was higher in the year in which a woman was forcibly displaced and lower in the year a woman migrated voluntarily. Residency in a new site increased the risk of pregnancy for both.  相似文献   
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In this paper, we seek to identify factors that account for the declining school performance of boys and young men. After reviewing and analysing the international literature on gender and education, we integrate various explanatory approaches into a model that is rooted in the theory of socialisation. The model focuses on the developmental tasks which young men face during adolescence. Our central thesis is that the declining school performance of young men cannot be fully explained by their failure to cope with educational challenges, i.e., their problems with respect to the developmental task “qualification”. Rather, a comprehensive explanation requires the incorporation of three other central developmental tasks, “social attachments”, “regeneration”, and “participation”. In the last decades, it has become easier for young women to cope with these tasks than it is for young men. Thus a rare sociological incident has occurred: the reversal of centuries-old pattern of social stratification. Nowadays, young women and not young men acquire the privileged certificates offered by the educational system, and it is them who gain the more promising career prospects. Our thesis can be supported with data from a broad range of international studies. The crucial implication is that supporting young men at school will show only limited results. Rather, to improve the school performance of young men, it is also necessary to address their deficits in coping with the other aforementioned developmental tasks, all of which point to challenges that young people are expected to master in today's individualised, achievement-oriented society.  相似文献   
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Summary.  We consider the problem of estimating the noise variance in homoscedastic nonparametric regression models. For low dimensional covariates t  ∈  R d ,  d =1, 2, difference-based estimators have been investigated in a series of papers. For a given length of such an estimator, difference schemes which minimize the asymptotic mean-squared error can be computed for d =1 and d =2. However, from numerical studies it is known that for finite sample sizes the performance of these estimators may be deficient owing to a large finite sample bias. We provide theoretical support for these findings. In particular, we show that with increasing dimension d this becomes more drastic. If d 4, these estimators even fail to be consistent. A different class of estimators is discussed which allow better control of the bias and remain consistent when d 4. These estimators are compared numerically with kernel-type estimators (which are asymptotically efficient), and some guidance is given about when their use becomes necessary.  相似文献   
15.
The assumption in the 1930s that poverty was the cause of all social problems was clearly not borne out in the Swedish experiment in creating social security through massive insurance and other programmes. The public debate from the middle of the 1960s has therefore been concerned with an examination and re-definition of the aims of social policies. The perception of the role and functions of the social welfare services consequently changed. In 1974 a Parliamentary Commission published its report on the principles the services should follow in the future. The report emphasizes that the social welfare services have a definite role in the restructuring of society, and it spells out ways in which this aim can be achieved.  相似文献   
16.
The conditions under which a mother gives birth greatly affect the health risk of both the mother and the child. This article addresses how local exposure to organized violence affects whether women give birth in a health facility. We combine geocoded data on violent events from the Uppsala Conflict Data Program with georeferenced survey data on the use of maternal health care services from the Demographic and Health Surveys. Our sample covers 569,201 births by 390,574 mothers in 31 countries in sub-Saharan Africa. We use a mother fixed-effects analysis to estimate the effect of recent organized violence events within a radius of 50 km of the home of each mother on the likelihood that her child is born in a health facility. The results indicate that geographical and temporal proximity to organized violence significantly reduces the likelihood of institutional births. Although the level of maternal health care overall is lower in rural areas, the negative effect of violence appears to be stronger in urban areas. The study further underscores the importance of household and individual resilience, indicating that the effect of organized violence on institutional child delivery is greater among poor and less-educated mothers.  相似文献   
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The Norwegian Fertility Survey of 1977 shows that most of the population make adequate use of contraception. Only 7 per cent of those who did not desire to become pregnant dit not use birth control. The reduction in fertility and changes in the age-specific fertility pattern have not been as great as one would expect. The younger cohorts have not had changes in fertility as great as the changes in contraception would imply, whereas the older ones have had even greater changes. We conclude that changes in the age-specific fertility pattern have not been causally dependent on the contraceptive pattern  相似文献   
20.
The present experiment examined whether infants’ visual prediction performance of the appearance of objects moving in space is related to their manual object exploration ability. Fifty‐five 7‐ to 8‐month‐old infants were tested. A visual object prediction paradigm was developed during which a three‐dimensional object was presented in a live eye‐tracking setting. During familiarization, the object rotated back and forth along the vertical axis. While the object was moving, two target parts of it were briefly occluded from view and uncovered again as the object changed its direction of motion. In the test phase, the entire object was rotated around 90° and now rotated along the horizontal axis. We recorded infants’ eye movements directed at the target locations and analyzed the prediction rates. All of the infants also participated in a manual object exploration task, in which they freely explored five toy blocks. Infants with a higher level of object exploration skill had higher prediction rates during test trials as compared to infants with less proficient object exploratory actions. The results support the interpretation that advanced manual object exploration experience is associated with infants’ advanced visual prediction ability of the appearance of objects moving in space.  相似文献   
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