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21.
Among policymakers, a common perception surrounding the effects of cash transfer programmes, particularly unconditional programmes targeted to families with children, is that they induce increased fertility. We evaluate the Zambian Child Grant Programme, a government unconditional cash transfer targeted to families with a child under the age of 5 and examine impacts on fertility and household composition. The evaluation was a cluster randomized control trial, with data collected over 4 years from 2010 to 2014. Our results indicate that there are no programme impacts on overall fertility. Our results contribute to a small evidence base demonstrating that there are no unintended incentives related to fertility due to cash transfers.  相似文献   
22.
Near misses are a special kind of reinforcement which increases one’s desire to play. The aim of this paper is to examine the perception of near misses in normal population. We used a slot machine simulation running on a PC, where participants had to play four rounds with different near miss ratios (0, 15, 30 and 45%). Our sample consisted of 159 individuals with mean age of 22.8 and with no or little gambling experience. For data analysis we used chi-squared goodness-of-fit test and exact binomial test. Despite the fact, that there was a notable effect of near misses results showed that the subjects could not perceive trials of them.  相似文献   
23.
The objective of this work was to summarise and evaluate the evidence showing that physical activity is a protector factor as regards falls in older people. Relevant studies were identified through a systematic search in the MEDLINE and Cochrane Library, under the keywords of accidental fall/numerical data and risk factors, and with the bibliographies of retrieved papers. The combined odds ratio (OR) [95% confidence interval] for physical activity was 0.75 [0.64, 0.88] with moderate heterogeneity (I 2?=?33%). For fall injury, it was 0.59 [0.47, 0.74] and, for falls in general, it rose to 0.94 [0.76, 1.17] with nil heterogeneity. The combined OR for sedentary factors was 1.14 [1.10, 1.82] with moderate heterogeneity (I 2?=?36%). Regular physical activity in daily life yields significant reduction in falls in older people, especially falls with injuries.  相似文献   
24.
Logarithmic general error distribution, an extension of the log-normal distribution, is proposed. Some interesting properties of the log GED are derived. These properties are applied to establish the asymptotic behavior of the ratio of probability densities and the ratio of the tails of the logarithmic general error and log-normal distributions, and to derive the asymptotic distribution of the partial maximum of an independent and identically distributed sequence obeying the log GED.  相似文献   
25.
利用测井资料,在剖析传统的测井评价油(气)层污染方法的基础上,介绍了利用BP神经网络这一现代数理统计新技术来实现测井多参数评定油气层污染程度的方法和技巧;以华北二连油田实际资料为例,建立了测井判释油气层污染的数学物理模型,并进行了模拟预测。结果表明:该法简便可行,对污染评价参数预测精度较高,对污染程度评价合理准确,可作为油(气)层污  相似文献   
26.
当前,农村地区彝族青年的婚姻困境问题明显,形式变异的"买卖婚"在强大的社会心理支撑下普遍存在,婚姻困境中的性别差异明显,青年男女的婚姻自由受到限制,固守传统婚姻形式造成多种社会问题。破解农村地区彝族青年婚姻困境,需要给予公共政策支持的外力推动,形成解决这一问题的内生动力,并最终帮助彝族青年男女突破婚恋的物质和精神束缚,促进农村地区婚姻进步和经济社会发展。  相似文献   
27.
In the context of a pilot study the effects of the educational-psychological intervention Introvision were tested with older long-term unemployed people. The project was accomplished in the time by 1.4.2010 to 31.12.2010 in co-operation between ARGE Paderborn and the research group Introvision. In the context of the project 16 employees of ARGE Paderborn participated in an advanced training to Introvision, 31 customers of ARGE Paderborn began a coaching to get introduction in Introvision and 20 have also finished. Nine customers decided to participate five individual coachings. The results show, that the offers have a high individual use for the participants. To the central changes belong improved handling of stress, decrease of social isolation, improved (self-) perception as well as a higher self-confidence and a more open co-operation between customers and employees of ARGE Paderborn. Besides four participation began a job on the first labour market and two could be connected to a honorary activity.  相似文献   
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29.
Most research on line design assumes that human operators perform independently from the status of the line. Recent empirical evidence is contradictory. Humans are likely to change their working speed if they might otherwise cause idle time (Schultz et al., Manage Sci 44(12):1595–1607, 1998). This peculiarity of worker behavior is observed in a variety of settings but little is still known about optimal line design that accounts for this more realistic modeling of worker behavior. Therefore, we analyze work allocation in a serial line with limited buffer capacity and adaptive human behavior. An extensive simulation study reveals that optimal work allocation in state-dependent models is different from classical state-independent models. A bowl-shaped work allocation might be suboptimal and design guidelines are more complicated. Depending on the extent of human reactions, a bowl-shaped, balanced, or reversed-bowl work allocation can be preferable.  相似文献   
30.
采用通用有限元程序ANSYS建立了移动式压力容器筒体外壁表面凹坑(轴向和周向)的有限元模型。结合筒体表面凹坑的应力理论计算,研究探讨了在恒定内压下,筒体表面凹坑缺陷处的应力分布与凹坑几何尺寸之间的关系。以第三强度理论作为仿真终止判据,获取凹坑各几何参量的阈值,利用MATLAB对阈值进行最小二乘拟合,绘制出凹坑缺陷的安全评估参考曲线。拟合结果表明:轴向和周向凹坑对筒体局部结构强度的影响不同,对应的安全评估参考曲线存在区别。  相似文献   
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