基于偏差改正的病态模型Liu估计的单位权方差无偏估计  

Bias-Corrected Estimation of Unit Weight Variance for Liu-Type Estimator of Ill-Posed Model

作　　者：丁斌芬 安洁玉 DING Binfen;AN Jieyu(School of Software and Blockchain,Jiangxi University of Applied Science,Nanchang 330100,China)

机构地区：[1]江西应用科技学院软件与区块链学院,南昌市330100

出　　处：《大地测量与地球动力学》2021年第12期1249-1252,1263,共5页Journal of Geodesy and Geodynamics

基　　金：江西省教育厅科技项目(JGG203008)。

摘　　要：对Liu估计残差偏差进行修正,并基于二次型的数学期望公式,利用偏差改正后的残差导出Liu估计解的近似无偏单位权方差估计式。2个算例分析结果表明,相比于传统基于有偏残差的单位权方差计算公式,本文公式计算的单位权方差与真值更为接近。In this paper, we correct the deviation in the residual and derive the almost unbiased formula for calculating the unit weight variance for Liu-type estimator based on the quadratic mathematical expectation formula. The analysis results of two examples show that the unit weight variance computed by the formula of this paper is closer to the true value than that by traditional formula, which is based on the biased residual.

关 键 词：病态模型 Liu估计 偏差改正 单位权方差 

分 类 号：P207[天文地球—测绘科学与技术]