A number of approaches are available to estimate MA parameters from the data [31].
Many of these methods apply AR parameter estimation to the “inverse process",
the process with the inverse spectrum (see software/ma_est.m).
Refinement of the estimate may be done by maximizing the exact PDF (10.6), (10.37),
or the approximate frequency-domain PDF (10.7), (10.38)
using the approach in (section 17.5).
For this we need the CR bound analysis.
