Suppose that I can do a Karhunen-Loeve expansion of a log-likelihood function $p(\bf{x};\theta)$ into N terms and that these accounts for a fraction $1-\delta$ of the total energy. Now consider estimation of $\theta$ based on the expansion.
Two questions: 1. Can I obtain a bound on the error of MLE based on the expansion to the true MLE? 2. Can I derive a new CRLB for the mismatched model?