Abstract: Regarding the variance component linear function minimum norm quadratic unbiased estimates,it is needed to solve the nonlinear simultaneous equation. Generally speaking,it does not have the explicit solution,but it can only obtain the iterative solution.In this paper,the relation for estimators of c′σ~2 is shown under the mixed model M=(y,Xβ,Uζ,σ~20V0)and its reduced models with V0≥0.

Key words: mixed model； variance components； minimum norm quadratic unbiased estimator；