调查内比估计效果的数据模拟分析——关于简单抽样设计与PPS系统抽样设计的比较

一、引言抽样设计的效率在于充分利用已知的辅助信息。我们知道,当辅助信息与目标变量之间具有较高的相关时,采用比估计方法可以提高抽样效率;当抽样单位的大小与目标变量之间有相关时,采用PPS抽样方法可以提高抽样效率。那么可以设想,在有辅助信息可以利用时,同时采用PPS抽样和比估计就可以更加提高抽样效率。我们利用一个省的农业普查数据进行模拟分析,证实了这一点。比估计是相对于简单估计而言的。简单估计量只涉及所估计的指标本身,不需要利用其他信息。而在实际调查中,调查通常是多指标的,一个指标的估计常常可以利用其他指标或历…     

大数据背景下网络调查样本的随机森林倾向得分模型推断研究

随着大数据与互联网技术的迅猛发展,网络调查的应用越来越广泛。本文提出网络调查样本的随机森林倾向得分模型推断方法,通过构建若干棵分类决策树组成随机森林,对网络调查样本单元的倾向得分进行估计,从而实现对总体的推断。模拟分析和实证研究结果表明:基于随机森林倾向得分模型的总体均值估计的相对偏差、方差与均方误差均比基于Logistic倾向得分模型的总体均值估计的相对偏差、方差与均方误差小,提出的方法估计效果更好。     

多主题抽样调查中改进估计方法的研究

多主题抽样调查在实际统计工作中非常普遍,即一项调查同时涉及两个或多个目标变量(指标),对总体的推算也需要同时对这两个或多个指标进行估计.通常同一调查中的多个目标变量之间会具有相关性,利用这一信息可以提高对所关注调查指标的估计精度.本文利用多重多元线性模型的方法研究这一问题,讨论了最佳线性模型无偏估计和一般回归估计,可以看到借助调查指标之间的相关性,较之常用的单个响应变量的多元线性回归模型方法,得到的最佳线性模型无偏估计和一般回归估计都可以有效地提高对总体总量的估计精度,本文的数值模拟和实例分析也验证了这一结论.     

CSI模型样本量的Monte Carlo研究

文章从实际应用的角度对满意度模型进行了分析,并通过前人的研究对两种估计方法进行了多方面的比较;运用Monte Carlo模拟对CSI实用中样本量问题进行了探讨:应用proactive Monte Carlo证明PLS在小样本下估计效果比LISREL更具稳健性,又应用reactive Monte Carlo模拟证明PLS对样本量也有要求,并非任何小样本都适用。     

纵向数据下半参数Logistic模型的变量选择

文章研究了纵向数据半参数Logistic回归模型的估计问题,给出了模型中未知参数和未知函数的估计方法,探讨了参数部分的变量选择问题,并对不同的变量选择方法进行比较分析.从模拟结果可以看到,文中给出的方法具有很好的估计效果.     

分层拉丁超立方体抽样方法及应用

为了提高样本数据的质量，文章提出了一种新的抽样方法——分层拉丁超立方体抽样，给出了该抽样方法的定义以及实现算法，证明了在相应条件下该抽样方法的估计精度比分层随机抽样方法更高，可以更有效地缩减蒙特卡罗方差。同时，还通过数值模拟比较了分层拉丁超立方体抽样与分层随机抽样在用蒙特卡罗方法估计定积分时的效果，数值模拟结果验证了上述结论的正确性。     

双总体假设检验的另类区间估计法及其MCS研究

文章根据区间估计与假设检验的关系,通过构造大概率事件,利用另类区间估计检验方法,对双总体常见的参数假设检验给出了检验方法;并利用蒙特卡罗模拟方法从实验的角度对该检验方法进行了验证,证实了另类区间估计方法不但可以对原假设成立时进行假设检验,对原假设不成立时也有满意的检验效率.     

比估计法在人口调查中的应用

在大规模的人口调查中,一般是用分层随机抽样方法抽取典型样本地区,然后在典型样本地区进行实地的人口核查。文章分别运用统计方法中的简单线性回归估计和较复杂的非线性比估计,估计总体的均值和标准差,通过精度的比较确定在人口调查中的最优估计方法。     

异方差模型参数估计的有效性研究

本文运用随机模拟方法,对误差序列异方差模型中加权最小二乘（GLS）估计的有效性进行研究。研究表明,GLS估计的有效性与异方差强度有关,当异方差强度较强时,GLS估计比普通最小二乘（OLS）估计有效;当异方差强度较弱时,GLS估计不如OLS估计有效。     

基于多重抽样框的连续性抽样估计方法研究

多重抽样框可以解决单一抽样框难以完整覆盖流动性目标总体的难题,连续性抽样调查则可以获取变量的时序观测数据,对总体现象进行追踪调查。本文将多重抽样框调查与连续性抽样调查两种方法结合在一起进行研究,深入分析基于多重抽样框的连续性抽样估计方法。文章首先设计了连续性调查环境下总体结构变动表;然后,在简单随机抽样假定下的轮换样本调查情形开展研究,设计了14种参数缩减方法对构建的似然函数进行估计求解,并给出了估计量的迭代计算过程;最后,对本文的研究内容进行了总结与展望。     

Examination of Influential Observations to Improve Discriminant Analysis

Three simple transformations are proposed in the context of ratio and product methods of estimation, based on any probability sampling design, and the usual unbiased estimation under varying probability sampling. These transformations may be effected

after the data are collected in a survey. The objective is to obtain improved estimators of the population total     

On stratified bivariate ranked set sampling with optimal allocation for naïve and ratio estimators

The purpose of the current work is to introduce stratified bivariate ranked set sampling (SBVRSS) and investigate its performance for estimating the population mean using both naïve and ratio methods. The properties of the proposed estimator are derived along with the optimal allocation with respect to stratification. We conduct a simulation study to demonstrate the relative efficiency of SBVRSS as compared to stratified bivariate simple random sampling (SBVSRS) for ratio estimation. Data that consist of weights and bilirubin levels in the blood of 120 babies are used to illustrate the procedure on a real data set. Based on our simulation, SBVRSS for ratio estimation is more efficient than using SBVSRS in all cases.     

Ratio estimator for the population mean using ranked set sampling

We adapt the ratio estimation using ranked set sampling, suggested by Samawi and Muttlak (Biometr J 38:753–764, 1996), to the ratio estimator for the population mean, based on Prasad (Commun Stat Theory Methods 18:379–392, 1989), in simple random sampling. Theoretically, we show that the proposed ratio estimator for the population mean is more efficient than the ratio estimator, in Prasad (1989), in all conditions. In addition, we support this theoretical result with the aid of a numerical example.      

相关差别指标的区间估计方法比较

在公共疾病控制领域，重大稀有疾病的发病率非常低，符合逆抽样特征，量化分析重大稀有疾病的发病率并对其特点进行分析。为了研究在带有群内相关条件下的整群抽样问题，通过二项分布抽样对比流行病学中相关差别指标的六种渐近置信区间的构造方法研究，综合考虑实际覆盖率与区间长度对各种方法的优劣及适用情况做出对比分析。研究表明，Wald型置信区间与对数变换的置信区间对发病率的估计表现因参数而定，而Bootstrap类方法不稳定。本研究找出了不同区间估计方法的适用场合，应合理看待置信区间这种评估方法在流行病学中的实际应用。     

相关差别指标的区间估计方法比较

在公共疾病控制领域,重大稀有疾病的发病率非常低,符合逆抽样特征,量化分析重大稀有疾病的发病率并对其特点进行分析,为了研究在带有群内相关条件下的整群抽样问题,通过β-二项分布抽样对比流行病学中相关差别指标的六种渐近置信区间的构造方法,综合考虑实际覆盖率与区间长度对各种方法的优劣及适用情况并对比分析。研究表明,Wald型置信区间与对数变换的置信区间对发病率的估计表现因参数而定,而Bootstrap类方法不稳定。本研究找出了不同区间估计方法的适用场合,认为应合理看待置信区间这种评估方法在流行病学中的实际应用。     

不等概率抽取群单位时样本量的间接计算

讨论了应用设计效应间接计算不等概率抽群的单级整群抽样和二阶段抽样方案样本量的问题,其中包括：所论抽样方案设计效应的估计;估计所论总体的方差,并根据精度要求计算简单随机抽取基本抽样单元时所需的样本量;用设计效应将上述样本量换算成所论抽样方案需要的样本量。     

Methods improving the estimate of diagnostic odds ratio

Diagnostic odds ratio is defined as the ratio of the odds of the positivity of a diagnostic test results in the diseased population relative to that in the non-diseased population. It is a function of sensitivity and specificity, which can be seen as an indicator of the diagnostic accuracy for the evaluation of a biomarker/test. The naïve estimator of diagnostic odds ratio fails when either sensitivity or specificity is close to one, which leads the denominator of diagnostic odds ratio equal to zero. We propose several methods to adjust for such situation. Agresti and Coull’s adjustment is a common and straightforward way for extreme binomial proportions. Alternatively, estimation methods based on a more advanced sampling design can be applied, which systematically selects samples from underlying population based on judgment ranks. Under such design, the odds can be estimated by the sum of indicator functions and thus avoid the situation of dividing by zero and provide a valid estimation. The asymptotic mean and variance of the proposed estimators are derived. All methods are readily applied for the confidence interval estimation and hypothesis testing for diagnostic odds ratio. A simulation study is conducted to compare the efficiency of the proposed methods. Finally, the proposed methods are illustrated using a real dataset.     

An alternative to ratio estimator in post-stratification

This article proposes an alternative to usual ratio estimator of population mean in post-stratified sampling procedure and its properties are analyzed. Both theoretical and empirical findings are encouraging and support the soundness of the proposed procedure for mean estimation over an alternative to ratio estimator in simple random sampling without replacement suggested by Srivenkataramana and Tracy (1980), usual combined ratio estimators suggested by Ige and Tripathi (1989), and usual unbiased estimator in post-stratified sampling scheme. Both theoretical and empirical findings are encouraging and support the soundness of the present study. At the end, a simulation study has been carried out to verify the superiority of the proposed estimator.     

Estimation of Population Mean in the Presence of Linear Trend

The present article deals with some methods for estimation of finite populations means in the presence of linear trend among the population values. As a result, we provided a strategy for the selection of sampling interval k for the case of circular systematic sampling, which ensures better estimator for the population mean compared to other choices of the sampling interval. This has been established based on empirical studies. Further we more, applied multiple random starts methods for selecting random samples for the case of linear systematic sampling and diagonal systematic sampling schemes. We also derived the explicit expressions for the variances and their estimates. The relative performances of simple random sampling, linear systematic sampling and diagonal systematic sampling schemes with single and multiple random starts are also assessed based on numerical examples.     

Systematic and nonrandom sampling in the presence of linear trends

In the case of a finite population with a linear trend, improvements in estimation procedures are suggested for several well-known systematic samplingschemes. The use of the least squares regression estimator is examined and a sampling scheme which reduces its expected mean squared error is proposed.