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首先概括性地阐述方差-协方差分量估计(VCE)理论的发展历史与研究现状;利用正交分解提取出等效残差,建立VCE的基本方程,在此基础上阐述VCE算法的局部最优特性和可能出现负定协方差阵估计结果等两大问题,并分析可能的解决方案及其复杂性;导出初值给定的Helmert、最小二乘和MINQUEVCE的线性逼近估计公式,证明基于等效残差的估计公式与已有VCE公式等价,各种估计方法在本质上是一致的;最后,用两个算例验证本文的观点。 更多还原

【Abstract】 The development of the variance-covariance component estimation(VCE)theory is firstly synoptically reviewed in this paper.Then the equivalent residuals are extracted by using orthogonal decomposition and the fundamental equations for VCE are established.Based on that the two profound and unresolvable problems for VCE theory,namely regional optimality and negative definition for estimated covariance matrix,are explored and the corresponding possible resolvable schemes and their complexity are ana... 更多还原