纺织高校基础科学学报
紡織高校基礎科學學報
방직고교기출과학학보
BASIC SCIENCES JOURNAL OF TEXTILE UNIVERSITIES
2014年
4期
459-462,481
,共5页
M eta分析%偏正态分布%偏倚%异质性
M eta分析%偏正態分佈%偏倚%異質性
M eta분석%편정태분포%편의%이질성
Meta analysis%skewed normal distribution%bias%heterogeneity
考虑M eta分析中偏倚对总体效应估计的影响。在模型中引入表示偏倚的参数,构造基于偏正态分布的模型,将偏倚与异质性同时纳入模型,并进行估计,由估计量分析偏倚对异质性和总体效应的影响。在基于偏正态分布的模型下,对总体效应量采用加权最小二乘估计,并进一步修正为无偏估计。与以往基于正态分布的模型相比,该模型将偏倚进行了量化,并从总体效应的估计中予以剔除,从而使合并效应量剔除了偏倚的影响,而且较基于正态分布的模型更符合实际情况。
攷慮M eta分析中偏倚對總體效應估計的影響。在模型中引入錶示偏倚的參數,構造基于偏正態分佈的模型,將偏倚與異質性同時納入模型,併進行估計,由估計量分析偏倚對異質性和總體效應的影響。在基于偏正態分佈的模型下,對總體效應量採用加權最小二乘估計,併進一步脩正為無偏估計。與以往基于正態分佈的模型相比,該模型將偏倚進行瞭量化,併從總體效應的估計中予以剔除,從而使閤併效應量剔除瞭偏倚的影響,而且較基于正態分佈的模型更符閤實際情況。
고필M eta분석중편의대총체효응고계적영향。재모형중인입표시편의적삼수,구조기우편정태분포적모형,장편의여이질성동시납입모형,병진행고계,유고계량분석편의대이질성화총체효응적영향。재기우편정태분포적모형하,대총체효응량채용가권최소이승고계,병진일보수정위무편고계。여이왕기우정태분포적모형상비,해모형장편의진행료양화,병종총체효응적고계중여이척제,종이사합병효응량척제료편의적영향,이차교기우정태분포적모형경부합실제정황。
The bias influences on the overall effect are considered in Meta analysis .The bias parameter was introduced to structure the model based on the skewed normal distribution .At the same time ,bias and heterogeneity were taken into account and estimated .The influence of bias to the heterogeneity and the overall effect was explained by the estimators .Based on the model of the skewed normal distribution , the overall effect was estimated by using the weighted least squares which was further corrected to be the unbiased estimator .Compared with the model based on normal distribution ,the bias is quantified and removed from the overall effect estimator ,so that the combined effect is gotten rid of the bias influence , and more in line with the actual situation .