Perform a score test for the given submodel against this model.
A fitted GEE model that is a submodel of this model.
The score test can be performed without calling ‘fit’ on the larger model. The provided submodel must be obtained from a fitted GEE.
This method performs the same score test as can be obtained by fitting the GEE with a linear constraint and calling score_test on the results.
Xu Guo and Wei Pan (2002). “Small sample performance of the score test in GEE”. http://www.sph.umn.edu/faculty1/wp-content/uploads/2012/11/rr2002-013.pdf