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1.
两种连续型随机变量未知参数的区间估计 总被引：1，自引：0，他引：1
区间估计是对总体分布中未知参数进行估计的一种重要方法,对指导实际生产有着重要意义。本文利用枢轴量方法,对指数分布和均匀分布中未知参数的置信区间的求法进行了讨论,对这两类分布中未知参数的区间估计有一定的指导作用。 相似文献
2.
李万斌 《四川教育学院学报》2010,26(11):107-108,116
通过分析构造枢轴量进行置信区间估计的过程,说明参数估计中优良的点估计与区间估计的关系。在此基础上,根据Lehmann-Sheffe定理说明充分统计量在构造枢轴量进行置信区间估计时的作用,指出了在进行置信区间估计时利用充分统计量构造枢轴量的有效途径。 相似文献
3.
在非正态总体情况下,参数统计中,连续性随机变量参数的估计与检验问题中,区间估计合适的枢轴量的构造是置信区间的难点,假设检验的有关统计量的分布确定也是解决问题的关键.对这些方面进行研究,某些情况下利用卡方分布分位数可以使问题解决. 相似文献
4.
文章主要讨论了两个0-1总体均具有部分缺失数据时的参数的极大似然估计,并证明了估计的强相合性和渐进正态性,给出了大样本场合下的似然比检验统计量的极限分布。 相似文献
5.
指数分布多个异常数据的检验 总被引：2，自引：2，他引：0
李云飞 《内江师范学院学报》2008,23(4):17-19
利用样本分位数构造检验统计量,给出来自于指数分布总体异常数据的一种检测方法．求出了检验统计量精确的概率密度函数和大样本情形下的近似分布,从而得到了检验临界值简洁的近似表达式．检验统计量中的核心统计量——样本分位数,对于异常数据的干扰具有一定的抵抗力,因此该方法可有效地达到检测效果． 相似文献
6.
通过讨论两总体方差差异的经验似然的大样本性质,证明了经验似然比统计量依分布收敛于X2随机变量,由此给出方差差异的经验似然置信区间. 相似文献
7.
曾艳 《赤峰学院学报(自然科学版)》2011,(9):12-13
在均匀分布参数的区间估计基础上,证明了最短置信区间的唯一存在性,给出了最短置信区间的具体形式,并对不同样本容量下最短置信区间长度与传统置信区间长度进行了对比分析．结果表明：不论样本容量大小如何,用最短tong．间作为未知参数的估计区间,估计的精确度都会得到显著的提高． 相似文献
8.
9.
Ⅰ型极小值分布样本异常数据的检验 总被引：1，自引：1，他引：0
针对Ⅰ型极小值分布样本的多个异常数据,提出了一种新的检验方法.首先寻找到总体参数的具有较好稳健性的估计量,然后在此基础上构造出检验统计量,进一步求出了该检验统计量精确的概率密度函数和大样本情形下的近似分布.由于检验统计量中的核心统计量——样本分位数,对于异常数据的干扰具有一定的抵抗力,因此利用该方法可以达到有效的检验效果. 相似文献
10.
构造了固定设计且误差为鞅差序列的相依样本情形部分线性模型非参数分量的经验似然比统计量,证明了统计量的极限分布为X1^2,在此基础上构造了部分线性模型非参数分量的经验似然置信区间． 相似文献
11.
研究了M/G/c排队系统中顾客队长、排队长的置信区间的求解方法.利用Bootstrap原理,给出了正态区间法、枢轴量法和百分位区间法等三种计算方法.实际应用表明,三种方法都得到了较好的结果.以置信区间的长度为评价标准,正态区间法和百分位区间法较优. 相似文献
12.
Paul T. von Hippel 《Structural equation modeling》2016,23(3):422-437
When analyzing incomplete data, is it better to use multiple imputation (MI) or full information maximum likelihood (ML)? In large samples ML is clearly better, but in small samples ML’s usefulness has been limited because ML commonly uses normal test statistics and confidence intervals that require large samples. We propose small-sample t-based ML confidence intervals that have good coverage and are shorter than t-based confidence intervals under MI. We also show that ML point estimates are less biased and more efficient than MI point estimates in small samples of bivariate normal data. With our new confidence intervals, ML should be preferred over MI, even in small samples, whenever both options are available. 相似文献
13.
张学新 《宁夏师范学院学报》2013,(6):21-25
首先模拟研究广义自助法置信区域的性能,选择不同权重、不同分布的数据,利用Matlab软件模拟其覆盖真值的比率,表明它是非渐近最优的,可适用于不同大小的样本.然后把广义自助法置信区域方法应用于检验地方政府GDP造假与虚假年份,获得比较可信的结果. 相似文献
14.
Todd E. Bodner 《Structural equation modeling》2013,20(4):651-675
When using multiple imputation in the analysis of incomplete data, a prominent guideline suggests that more than 10 imputed data values are seldom needed. This article calls into question the optimism of this guideline and illustrates that important quantities (e.g., p values, confidence interval half-widths, and estimated fractions of missing information) suffer from substantial imprecision with a small number of imputations. Substantively, a researcher can draw categorically different conclusions about null hypothesis rejection, estimation precision, and missing information in distinct multiple imputation runs for the same data and analysis with few imputations. This article explores the factors associated with this imprecision, demonstrates that precision improves by increasing the number of imputations, and provides practical guidelines for choosing a reasonable number of imputations to reduce imprecision for each of these quantities. 相似文献
15.
加工中心MTBF值的点估计与区间估计 总被引：2，自引：0，他引：2
应用基于截尾数据的似然函数理论和Weibull分布下的似然比方法,对加工中心有替换定时截尾试验数据分别进行了加工中心平均故障时间间隔(MTBF)值的点估计与区间估计。根据似然函数的重要引理,用迭代方法进行了Weibull模型两个参数的区间估计,并进行了MTBF值的区间估计。本研究解决了加工中心可靠性评估工作中的难题。 相似文献
16.
基于Logistic响应模型,在二元响应数据下,将待估计的响应刺激量变换为模型的一个参数,应用鞍点逼近方法给出了该响应刺激量估计条件分布的高阶近似公式.在此基础上,引入Fiducial模型,并应用Fiducial模型给出了响应刺激量的区间估计,通过蒙特卡罗数值模拟表明,在样本量较小时,给合Fiducial模型,应用鞍点逼近方法,能够较好地估计响应刺激量. 相似文献
17.
An interval estimation procedure for proportion of explained observed variance in latent curve analysis is discussed, which can be used as an aid in the process of choosing between linear and nonlinear models. The method allows obtaining confidence intervals for the R 2 indexes associated with repeatedly followed measures in longitudinal studies. In addition to facilitating evaluation of local model fit, the approach is helpful for purposes of differentiating between plausible models stipulating different patterns of change over time, and in particular in empirical situations characterized by large samples and high statistical power. The procedure is also applicable in cross-sectional studies, as well as with general structural equation models. The method is illustrated using data from a nationally representative study of older adults. 相似文献
18.
《Structural equation modeling》2013,20(3):458-469
A method for obtaining an approximate confidence interval for the difference in root mean square error of approximation-a widely used goodness-of-fit measure-of 2 structural equation models is discussed, which is based on an application of the bootstrap methodology. The confidence interval represents a useful tool when studying plausibility of parameter restrictions in nested structural equation models and can be used for examining the difference in fit, accounting for complexity, for any 2 models-whether nested or nonnested-fitted to the same data set. The method is illustrated on a numerical example. 相似文献
19.
Holmes Finch 《Journal of Experimental Education》2013,81(1):26-52
Discriminant Analysis (DA) is a tool commonly used for differentiating among 2 or more groups based on 2 or more predictor variables. DA works by finding 1 or more linear combinations of the predictors that yield maximal difference among the groups. One common goal of researchers using DA is to characterize the nature of group difference by interpreting the contributions of the individual predictors to this linear combination, often using structure coefficients (SC). The authors of this simulation study examine the utility of several methods for interpreting SCs. Results indicate that with samples greater than 100, a bootstrap confidence interval may be optimal, whereas with smaller samples, common rules of thumb may work best. Furthermore, nonnormal data and unequal covariance matrixes diminish the effectiveness of SCs as an interpretive tool. 相似文献
20.
侯万儒 《重庆大学学报(英文版)》2005,4(2):117-120
1 Introduction 1 Myocardium enzyme includes Creatin Kinase (CK: EC2.7.3.2) and its isozyme (CK-MB), Lactate Dehydrogenase (LDH: EC1.1.1.27), α-hydrxybutyrate Dehydrogenase (HBDH) and Glutamic Oxalic Transaminase (GOT: EC2.6.1.1). The black bear (Ursus thibetanus, black bear ) is a kind of animal of great economic and academic attraction, and is included in the List of Level 2 Endangered Species of Animals in China. Extensive research has been done involving the black bear in su… 相似文献