首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   114篇
  免费   3篇
管理学   19篇
民族学   2篇
人口学   8篇
丛书文集   2篇
理论方法论   16篇
综合类   5篇
社会学   53篇
统计学   12篇
  2023年   2篇
  2022年   2篇
  2021年   2篇
  2020年   4篇
  2019年   5篇
  2018年   6篇
  2017年   9篇
  2016年   3篇
  2015年   3篇
  2014年   4篇
  2013年   17篇
  2012年   8篇
  2011年   6篇
  2010年   5篇
  2009年   3篇
  2008年   5篇
  2006年   5篇
  2005年   1篇
  2004年   2篇
  2003年   1篇
  2002年   4篇
  2001年   1篇
  2000年   4篇
  1998年   3篇
  1995年   1篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1983年   2篇
  1980年   1篇
  1973年   1篇
排序方式: 共有117条查询结果,搜索用时 15 毫秒
51.
Although generalized linear mixed models are recognized to be of major practical importance, it is also known that they can be computationally demanding. The problem is the evaluation of the integral in calculating the marginalized likelihood. The straightforward method is based on the Gauss–Hermite technique, based on Gaussian quadrature points. Another approach is provided by the class of penalized quasi-likelihood methods. It is commonly believed that the Gauss–Hermite method works relatively well in simple situations but fails in more complicated structures. However, we present here a strikingly simple example of a logistic random-intercepts model in the context of a longitudinal clinical trial where the method gives valid results only for a high number of quadrature points ( Q ). As a consequence, this result warns the practitioner to examine routinely the dependence of the results on Q . The adaptive Gaussian quadrature, as implemented in the new SAS procedure NLMIXED, offered the solution to our problem. However, even the adaptive version of Gaussian quadrature needs careful handling to ensure convergence.  相似文献   
52.
53.
The current study aimed to evaluate how adolescents' and parents' perceptions of daily parenting—and their discrepancies—relate to daily parent and adolescent affect. Daily parental warmth and affect were assessed using electronic diaries in 150 American adolescent–parent dyads (61.3% females, Mage = 14.6, 83.3% White; 95.3% mothers, Mage = 43.4; 89.3% White) and in 80 Dutch adolescents with 79 mothers and 72 fathers (63.8% females, Mage = 15.9, 91.3% White; Mage = 49.0, 97.4% White). Results of preregistered models indicated that individuals' affect may be more important for perceptions of parenting than discrepancies between parent–adolescent reports of parenting for affect, stressing the need to be aware of this influence of affect on parenting reports in clinical and research settings.  相似文献   
54.
This study aimed to analyze the impact of step-duration protocols, 1-min vs. 3-min, on cardiorespiratory responses to exercise, whatever the aerobic-fitness level of sedentary (65.5 +/- 2.3 years, n = 8) or highly fit (63.1 +/- 3.2 years, n = 19) participants. Heart rate and VO2 at the first and second ventilatory thresholds (VT1 ,VT2) and maximal exercise were not significantly different between the two protocols. In master athletes, the 3-min protocol elicited significantly lower ventilation at VT2 and maximal exercise (p < .01). In the latter, breathlessness was also lower at maximal exercise (p < .05) than in sedentary participants. In trained or sedentary older adults, VT1, VT2, and were not influenced by stage duration. According to the lower breathlessness and ventilation, however, the 3-min step protocol could be more appropriate in master athletes. In untrained participants, because the cardiorespiratory responses were similar with the two incremental exercise tests, either of them could be used.  相似文献   
55.
56.
Few studies on remittances have focused on sub-Saharan Africa. This paper analyses a nationwide survey of 5,998 households to determine the characteristics of both internal and overseas remittances in Ghana. Particular attention is paid to the poverty-alleviation potential of remittances. Furthermore, this study uses a smaller scale pilot project with a matched sample of senders and receivers of remittances to identify some problems with using household-level surveys to assess the volume and impact of overseas remittances, and offers some suggestions as to how to handle these problems. The paper estimates that foreign remittances may be three times as large as Bank of Ghana estimates, bringing Ghana on par with large remittance receiving countries such as the Philippines and Mexico. The paper concludes that while foreign remittances are larger in value, locally sent remittances reach poorer segments of the population. Both foreign and local remittances are unevenly geographically distributed, being received more in the centre and southern regions than in northern Ghana where the poorest regions are. The paper argues a need to study multiplier effects of foreign remittances, as these can be large and eventually accrue to rural populations.  相似文献   
57.
58.
A relative invariant and an absolute invariant inequality ordering satisfying extreme bottom-sensitivity, are proposed. It is shown that the leximin social welfare ordering can be expressed in terms of a ranking of distributions on the sole basis of their size, measured by the mean, and the degree of inequality, measured according to these inequality concepts. Leximin thus exhibits extreme bottom-sensitivity. This property does not withstand that leximin prefers a larger size of the cake at the cost of higher inequality in a number of cases. These trade-offs between size and equality are characterised in terms of degrees of dominance of the lower parts of the ordinary and absolute Lorenz curves that are accepted by leximin for a given increase in the mean.  相似文献   
59.
60.
Personal identity formation constitutes a crucial developmental task during the teens and 20s. Using a recently developed five‐dimensional identity model, this cross‐sectional study (N = 5834) investigated age trends from ages 14 to 30 for different commitment and exploration processes. As expected, results indicated that, despite some fluctuations over time, commitment processes tended to increase in a linear fashion. Exploration in breadth and exploration in depth were characterized by quadratic trends, with the highest levels occurring in emerging adulthood. Further, the functionality of these identity processes, and especially of exploration, changed over time. Exploration in breadth and exploration in depth were strongly related to commitment processes especially in adolescence and emerging adulthood, but these exploration processes became increasingly associated with ruminative exploration and depressive symptoms in the late 20s. Theoretical implications and suggestions for future research are outlined.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号