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   53篇
  免费   1篇
管理学   18篇
人口学   3篇
理论方法论   7篇
社会学   20篇
统计学   6篇
  2021年   1篇
  2020年   1篇
  2019年   5篇
  2018年   2篇
  2017年   3篇
  2016年   2篇
  2015年   1篇
  2014年   2篇
  2013年   9篇
  2011年   1篇
  2010年   5篇
  2009年   3篇
  2008年   1篇
  2007年   4篇
  2006年   1篇
  2005年   2篇
  2004年   1篇
  2003年   3篇
  2002年   1篇
  2001年   1篇
  1994年   1篇
  1990年   1篇
  1982年   1篇
  1978年   1篇
  1976年   1篇
排序方式: 共有54条查询结果,搜索用时 15 毫秒
21.
Recent research on human nonverbal vocalizations has led to considerable progress in our understanding of vocal communication of emotion. However, in contrast to studies of animal vocalizations, this research has focused mainly on the emotional interpretation of such signals. The repertoire of human nonverbal vocalizations as acoustic types, and the mapping between acoustic and emotional categories, thus remain underexplored. In a cross-linguistic naming task (Experiment 1), verbal categorization of 132 authentic (non-acted) human vocalizations by English-, Swedish- and Russian-speaking participants revealed the same major acoustic types: laugh, cry, scream, moan, and possibly roar and sigh. The association between call type and perceived emotion was systematic but non-redundant: listeners associated every call type with a limited, but in some cases relatively wide, range of emotions. The speed and consistency of naming the call type predicted the speed and consistency of inferring the caller’s emotion, suggesting that acoustic and emotional categorizations are closely related. However, participants preferred to name the call type before naming the emotion. Furthermore, nonverbal categorization of the same stimuli in a triad classification task (Experiment 2) was more compatible with classification by call type than by emotion, indicating the former’s greater perceptual salience. These results suggest that acoustic categorization may precede attribution of emotion, highlighting the need to distinguish between the overt form of nonverbal signals and their interpretation by the perceiver. Both within- and between-call acoustic variation can then be modeled explicitly, bringing research on human nonverbal vocalizations more in line with the work on animal communication.  相似文献   
22.
23.
Clinical noninferiority trials with at least three groups have received much attention recently, perhaps due to the fact that regulatory agencies often require that a placebo group be evaluated along with a new experimental drug and an active control. The authors discuss likelihood ratio tests for binary endpoints and various noninferiority hypotheses. They find that, depending on the particular hypothesis, the test reduces asymptotically either to the intersection‐union test or to a test which follows asymptotically a mixture of generalized chi‐squared distributions. They investigate the performance of this asymptotic test and provide an exact modification. They show that this test considerably outperforms multiple testing methods such as the Bonferroni adjustment with respect to power. They illustrate their methods with a cancer study to compare antiemetic agents. Finally, they discuss the extension of the results to other settings, such as Gaussian endpoints.  相似文献   
24.
Elective surgery management typically deals with a queue of patients that have to be scheduled for surgery within a certain time frame, considering both medical and economic constraints. In order to prevent the patient queue and waiting times from growing, surgery management has to decide whether to temporarily increase patient throughput at the regional hospital or have some patients scheduled for surgery at another hospital. In Sweden, a newly passed law states that patients who decide to receive surgery should not have to wait more than 90 days before this surgery is carried out. Therefore, if a patient decides to apply the new law by requesting surgery within 90 days, the regional hospital is obliged to arrange and pay for either in-house surgery or surgery at another hospital. In this paper, we suggest an approach using simulation including optimization for modeling surgery management decisions. We study a case based on data from a General Surgery Department at a Swedish hospital and present our results as a health economic evaluation. The results indicate an increase in the mean waiting times for medium prioritized patients when the new law is applied.  相似文献   
25.
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   
26.
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   
27.
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   
28.
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   
29.
Performance‐based promotion schemes in administrative hierarchies have limitations. Chinese provincial leaders, despite facing strong career concerns, make different policy decisions depending on their career backgrounds. Provincial party secretaries who have risen from low to high positions within the province they govern (“locals”) spend a higher share of budgetary resources on education and health care and invest less in construction infrastructure than party secretaries who have made their most significant career advancements in other provinces (“outsiders”). Identification comes from variation in central leadership and term limits. As the promotion mechanism rewards infrastructure investments, locals are less likely to be promoted at the end of the term. We explore various mechanisms and provide evidence that the difference between locals and outsiders is not driven by knowledge or experience. Several pieces of evidence suggest that locals cater to low‐level provincial elites, who helped them rise to power. Thus, local career trajectories limit the power of career concerns by fostering competing allegiances.  相似文献   
30.
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   
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