In this paper I glossed over several problems.
First, should be a space-varying function rather than
the constant I proposed. A bootstrap approach (using
the model residual at one non-linear iteration as our guess
at a space-varying ) might prove effective but hasn't been
tested. How to calculate for the non-missing data problem
is an open question. In the generic geophysical operator , we often
don't know
which model components are estimated through the data fitting
goal and which are estimated by the model styling goal.
Finally, I made the assumption that I was dealing with
models with a normal distribution.
Whether replacing with another distribution
or using something similar to the geostatistician's normal-score transform
would be effective in correctly modeling these distributions is unknown.