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   45篇
  免费   0篇
民族学   1篇
人口学   4篇
社会学   3篇
统计学   37篇
  2020年   1篇
  2019年   3篇
  2018年   6篇
  2017年   13篇
  2016年   2篇
  2014年   1篇
  2013年   15篇
  2012年   1篇
  2010年   1篇
  2008年   1篇
  2007年   1篇
排序方式: 共有45条查询结果,搜索用时 31 毫秒
1.
We conducted this research based on a qualitative approach to describe the opinions of older widows and widowers on remarriage obstacles. Based on purposive sampling and inclusion criteria, we chose 48 participants on maximum diversity of sex, age, education, employment, and socioeconomic status. Two thirds of the participants were female, 40% had spent more than 10 years widowed, and 65% were living with their children. We collected data individually through semistructured, face-to-face interviews. Based on conventional content analyses, 2 independent researchers implemented data analysis manually. Barriers to remarriage were finally categorized into 4 main themes: personal, normative, interactive, and financial factors. Results of this study showed that older people are more concerned about public opinions and social norms surrounding remarriage. As long as these thoughts and norms are not changed, the concept of remarriage among widows and widowers remains a vital taboo and concern.  相似文献   
2.
Heart rate is associated with work hardness and increase linearly with its increasing. In the average of energy consumption, heart rate measurement is simple but non-accurate method for calculation of work hardness. Our purpose in this research was to evaluate the relationship between heart rate and dynamometry results with hypothesis of work hardness effectiveness on the human power. This study was conducted on 102 porcelain workers. Participants were selected randomly. The research tools include stethoscope, the dynamometer. Heart rate, and pinch, grip, and back-leg-chest force were measured and relationships between variables were analyzed with Pearson correlation test and independent T-test using Spss 16 software. The average heart rate of participants were 4.11 ± 1.79 with minimum 60 and maximum 120. The average force of pinch, grip, and back-leg-chest were 8.9 ± 3.20, 4.2 ± 4.5 and 9.36 ± 6.55, respectively. Work hardness for 3.86% of workers were light, 7.12% were moderate and 1% were heavy. Pinch, grip, and back-leg-chest force relation with heart rate were not significant (r=0.01, p=0.85), (r=-0.03, p=0.74), and (r=0.05, p= 0.59), respectively. There was no correlation between heart rate and work hardness. So we can't use the dynamometry results to determine of work hardness.  相似文献   
3.
In this article, we introduce for the first time, the blank card methods for estimation of finite population mean of a sensitive variable. Two generic randomization devices are suggested, and for each device we identify the choices of special models. We introduce additive, multiplicative, and combination of both additive and multiplicative scrambling models that require use of a non sensitive variable. We derive the basic statistical properties of each model. It is interesting to note that various existing estimators can be viewed as the special cases of those presented here. The statistical efficiency of proposed techniques is compared with Greenberg et al. (1971 Greenberg, B.G., Kuebler Jr, R.R., Abernathy, J.R., Horvitz, D.G. (1971). Application of the randomized response technique in obtaining quantitative data. J. Am. Stat. Assoc. 66(334):243250.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) and modified Perri (2008 Perri, P.F. (2008). Modified randomized devices for Simmons’ model. Model Assisted Stat. Appl. 3(3):233239. [Google Scholar]) model. The proposed devices can easily be adjusted to achieve the required efficiency level by making suitable choices of different design parameters.  相似文献   
4.
We propose an improved difference-cum-exponential ratio type estimator for estimating the finite population mean in simple and stratified random sampling using two auxiliary variables. We obtain properties of the estimators up to first order of approximation. The proposed class of estimators is found to be more efficient than the usual sample mean estimator, ratio estimator, exponential ratio type estimator, usual two difference type estimators, Rao (1991) estimator, Gupta and Shabbir (2008) estimator, and Grover and Kaur (2011) estimator. We use six real data sets in simple random sampling and two in stratified sampling for numerical comparisons.  相似文献   
5.
Kadilar and Cingi [Ratio estimators in simple random sampling, Appl. Math. Comput. 151 (3) (2004), pp. 893–902] introduced some ratio-type estimators of finite population mean under simple random sampling. Recently, Kadilar and Cingi [New ratio estimators using correlation coefficient, Interstat 4 (2006), pp. 1–11] have suggested another form of ratio-type estimators by modifying the estimator developed by Singh and Tailor [Use of known correlation coefficient in estimating the finite population mean, Stat. Transit. 6 (2003), pp. 655–560]. Kadilar and Cingi [Improvement in estimating the population mean in simple random sampling, Appl. Math. Lett. 19 (1) (2006), pp. 75–79] have suggested yet another class of ratio-type estimators by taking a weighted average of the two known classes of estimators referenced above. In this article, we propose an alternative form of ratio-type estimators which are better than the competing ratio, regression, and other ratio-type estimators considered here. The results are also supported by the analysis of three real data sets that were considered by Kadilar and Cingi.  相似文献   
6.
Abstract

This article addresses the problem of estimating population distribution function for simple random sampling in the presence of non response and measurement error together. We suggest a general class of estimators for estimating the cumulative distribution function using the auxiliary information. The expressions for the bias and mean squared error are derived up to the first order of approximation. The performance of the proposed class of estimators is compared with considered estimators both theoretically and numerically. A real data set is used to support the theoretical findings.  相似文献   
7.
8.
We propose a generic randomization device (RD) for the estimation of mean of quantitative sensitive characteristic that make use of additive and multiplicative scrambled responses with blank card strategy. For this generic RD, we work with 12 choices and derive statistical properties of each model and give many immediate results in corollaries. It is interesting to note that various existing models can now be viewed as the special cases of this RD. Finally, various empirical studies have been done for each of these models to evaluate the efficiency performance.  相似文献   
9.
In this article, we propose a new class of estimators to estimate the finite population mean by using two auxiliary variables under two different sampling schemes such as simple random sampling and stratified random sampling. The proposed class of estimators gives minimum mean squared error as compared to all other considered estimators. Some real data sets are used to observe the performances of the estimators. We show numerically that the proposed class of estimators performs better as compared to all other competitor estimators.  相似文献   
10.

Objective

To investigate pregnant women’s decision making in relation to their choice of birthing hospital and, in particular, their priorities regarding hospital characteristics.

Methods

The focus of this study was the choice of birthing hospital among pregnant women. A qualitative interview design was used and women were recruited during their first pregnancy-related visit to a general practitioner. The interviews were conducted using a semi-structured interview guide, and a thematic analysis of the data was carried out.

Results

Women made their hospital choice decision independently and they relied extensively on their own or peers’ experiences. Travel distance played a role, but some women were willing to incur longer travel times to give birth at a specialized hospital in order to try to reduce the risks (in case of unexpected events). The women associated the presence of specialized services and staff that were more qualified and experienced with increased safety. Other priorities included continuity of care (i.e., being seen by the same midwife) as well as service availability, which in this case referred to the possibility of a water birth and postnatal hoteling services.

Conclusions

The choice of hospital provider appears to be strongly influenced by experience, whether personal experience or the experience of peers. However, there appears to be room for more information to be provided on safety and service attributes as an instrument for making an informed decision.  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