全文获取类型
收费全文 | 113篇 |
免费 | 2篇 |
专业分类
管理学 | 10篇 |
人口学 | 27篇 |
丛书文集 | 2篇 |
理论方法论 | 5篇 |
综合类 | 4篇 |
社会学 | 26篇 |
统计学 | 41篇 |
出版年
2021年 | 4篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 22篇 |
2012年 | 7篇 |
2011年 | 3篇 |
2010年 | 6篇 |
2009年 | 7篇 |
2008年 | 4篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2003年 | 1篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 10篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1978年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有115条查询结果,搜索用时 15 毫秒
11.
In this paper, we study the effects of nonnormality on the distributions of sample canonical correlations when the population canonical correlations are simple. In order to achieve the purpose, we derive asymptotic expansion formulas for the distributions of a function of the canonical correlations as well as the individual canonical correlations under nonnormal populations. We particularly discuss the distribution of sample canonical correlations under the class of elliptical population. These expansions are given by using a perturbation method. Simulation results are also given. 相似文献
12.
13.
The Bates–Watts relative curvature measure can assess the validity of the linearized approximation in nonlinear regression models. However, it is developed based on an ordinary nonlinear regression in which the observation is assumed to be homoscedastically and normally distributed. In this article, we extend the original Bates–Watts relative curvature measure to one that can be applicable to nonlinear regression with heteroscedastic or non normal data, based on the transformation-both-sides (TBS) approach. In pharmacokinetic models, a diagnostic use of their measures is illustrated. By means of a simulation experiment, the performance of the relative curvature measure for the TBS approach is evaluated. 相似文献
14.
AbstractWe suggest shrinkage based technique for estimating covariance matrix in the high-dimensional normal model with missing data. Our approach is based on the monotone missing scheme assumption, meaning that missing values patterns occur completely at random. Our asymptotic framework allows the dimensionality p grow to infinity together with the sample size, N, and extends the methodology of Ledoit and Wolf (2004) to the case of two-step monotone missing data. Two new shrinkage-type estimators are derived and their dominance properties over the Ledoit and Wolf (2004) estimator are shown under the expected quadratic loss. We perform a simulation study and conclude that the proposed estimators are successful for a range of missing data scenarios. 相似文献
15.
Tomoyuki Kakizume Fanghong Zhang Yohei Kawasaki Takashi Daimon 《Pharmaceutical statistics》2020,19(1):71-83
A randomized exploratory clinical trial comparing an experimental treatment with a control treatment on a binary endpoint is often conducted to make a go or no‐go decision. Such an exploratory trial needs to have an adequate sample size such that it will provide convincing evidence that the experimental treatment is either worthwhile or unpromising relative to the control treatment. In this paper, we propose three new sample‐size determination methods for an exploratory trial, which utilize the posterior probabilities calculated from predefined efficacy and inefficacy criteria leading to a declaration of the worthwhileness or unpromisingness of the experimental treatment. Simulation studies, including numerical investigation, showed that all three methods could declare the experimental treatment as worthwhile or unpromising with a high probability when the true response probability of the experimental treatment group is higher or lower, respectively, than that of the control treatment group. 相似文献
16.
This article discusses educational aspects of cross-cultural psychology in relationship to Japanese society. After exploring the present status of cross-cultural psychology in Japan, the paper delineates the factual, theoretical, and methodological implications of cross-cultural psychology for the teaching of psychology in Japanese universities. It is argued that an area approach incorporating comparative research on Japanese society can add context, detail, historical perspective, new methodology, and interdisciplinary richness to classes otherwise relying on traditional journal articles and textbooks of cross-cultural psychology. Such an approach is deemed useful for cross-cultural psychology classes taking place both inside and outside Japan. The article concludes with an annotated bibliography of research on Japanese society. 相似文献
17.
A survey of a random sample of licensed social workers in Virginia showed 98.8% had Internet access in either their home or workplace. A comparison of this study with a study conducted in the early 2000s indicated more than 20% difference regarding e-mail communication with clients and Internet use for work-related research. Social workers who actually used the Internet and e-mail tended to expect a future increase in their use, in contrast with nonusers. Stepwise multiple logistic regression analyses found age and type of agency (private/for-profit) as factors negatively related to having Internet access in the workplace, age, and the reason “E-mail is not secure enough” as factors negatively related in the future e-mail communication with clients among current nonusers. 相似文献
18.
Shigeki Koshida Tetsuo Ono Shunichiro Tsuji Takashi Murakami Hisatomi Arima Kentaro Takahashi 《Women and birth : journal of the Australian College of Midwives》2019,32(2):127-130
Background
Decreased fetal movements are associated with adverse perinatal outcomes, including stillbirth. Delayed maternal visits to a health care provider after perceiving decreased fetal movements are frequently observed in stillbirths. Informing pregnant women of the normal range of fetal movement frequency is essential in their earlier visits in order to prevent stillbirth.Aim
To investigate the fetal movement frequency in late pregnancy and the effects of associated perinatal factors.Methods
This prospective multicenter study was conducted in 20 obstetric facilities in our region of Japan. A total of 2337 pregnant women were asked to record the time it took to perceive 10 fetal movements by the modified ‘count to 10’ method every day from 34 weeks of gestation until delivery.Findings
The 90th percentile of the time for the maternal perception of 10 fetal movements was 18–29 min, with a gradually increasing trend toward the end of pregnancy. The numbers of both pregnant women giving birth after 39 weeks’ gestation and infants with a birth weight exceeding 3000 g were significantly higher in mothers who took ≥30 min to count 10 fetal movements than in those who took <30 min.Conclusion
The maternal perception time of fetal movements shows a gradually increasing trend within 30 min for 10 fetal movements by the modified ‘count to 10’ method. Informing pregnant women of the normal range of the fetal movement count time will help improve the maternal recognition of decreased fetal movements, which might prevent fetal death in late pregnancy. 相似文献19.
20.
Nils Chr Stenseth Ottar N. Bj?rnstad Takashi Saitoh 《Researches on Population Ecology》1998,40(1):85-95
We interpret gradients in population dynamics of the gray-sided vole from the southwestern part of the island of Hokkaido
to its northeastern part within the framework of a phenomenological model involving the relative length of summer and winter.
In Hokkaido, as in other northern regions, both spring and fall is considered as short transition periods between the two
main seasons — summer (the primary breeding season) and winter (the non-reproductive or secondary breeding season). We show
that the geographic transition in dynamics may be understood as the combined consequence of different patterns of density-dependence
during summer and winter, and geographically varying season lengths. Differences are shown to exist between summer and winter
with respect to strength of density-dependence. Direct density-dependence, in particular, is stronger during winter than during
summer. A model is presented to show how relative lengths of seasons can induce both stable and periodically fluctuating population
dynamics. The results are compared and contrasted with what is otherwise known about the gradient in rodent dynamics in Fennoscandia. 相似文献