Here we demonstrate the matrix algebra involved in solving the mixed model equations. For this small example, we will not actually estimate the variance components from the data but instead will use fixed values for the variance components as if they were estimated (or known) a priori ( =1 and =0.1 in this example). This is seldom the case in practice and later we will see how mixed models provide a powerful tool to simultaneously obtain both solutions for fixed and random effects and estimates of variance components.
From the model outlined above, the solutions for fixed effects (BLUEs) are: