In this note, the basic lemma of the linear identification problem is revisited. By utilizing a joint decomposition of orthogonal projectors as partitioned matrices, a new proof of the lemma is proposed. From the algebraic point of view, the present proof might be the simplest from among all...

This paper considers the problem of estimating, and testing for, a Kronecker product covariance structure of three-level (multiple time points (p), multiple sites (u), and multiple response variables (q)) multivariate data. Testing of such covariance structures is potentially important when not...