my problem is the following:
Let ∑0 be a symmetric matrix and ∑ its estimator. Also define F0 and its estimator F such that |∑ - ∑0|=O(T-1/2) and | F - F0|= O(N-1/2). After some manipulations that involved other matrices/processes, I get that |∑ - F0∑0F0t | = O(T-1/2 + N-1/2) (where I use superscript t for transpose) and also |F∑Ft - F0∑0F0t| = O(T-1/2 + N-1/2). Now let S0 be the matrix of eigenvectors associated with the r distinct positive eigenvalues of F0∑0F0t an S is the matrix of eigenvectors associated with r distinct positive eigenvalues of ∑.
The convergence rate of |S-S0| is what?
I believe we have |S-S0| = O(T-1/2 + N-1/2) but I couldn't prove it. I think it is necessary to use the Bauer-Fike Theorem (Theorem 7.2.2 of Golub and Van Loan 2013) but algebra is not my strongest point. Can someone please present-me a comprehensive proof of this.
Thanks.