This methods function reports a summary more similar to
summary.gam from mgcv than
summary.gam() from gam.
It applies to G2-VGAMs using
sm.os and O-splines, else
sm.ps and P-splines.
In particular, the hypothesis test for whether each
sm.os or
sm.ps
term can be deleted follows quite closely to
summary.gam.
The p-values from this type of test tend to be biased downwards (too
small)
and corresponds to p.type = 5.
It is hoped in the short future that improved p-values be implemented,
somewhat like the default of
summary.gam.
This methods function was adapted from
summary.gam.