I am trying to estimate covariance in multiple time series. However, I want to do this using a regime-switching framework. So, I start with fitting a GARCH(1,1) model and then de-volatalize the series....
We are testing Markov switching models to forecast risk regimes, similar to the paper by Kritzman, Page and Turkington. We find that in some cases the Baum-Welch algorithm converges very slowly or not ...