posum.fit {posum} | R Documentation |
This routine fits a population surface model to age structured
population data. It is not usually called directly, but is rather a service
routine for posum
. It is a modification of gam.fit
.
posum.fit(G, start = NULL, etastart = NULL, mustart = NULL, family = gaussian(), control = gam.control(), nb.iter = NULL)
G |
A modified version of the object returned by calls to gam.setup and GAMsetup . |
start |
optional parameter start values. |
etastart |
optional linear predictor start values. |
mustart |
optional fitted value start values. |
family |
family object - actually only gaussian , poisson or gamma with identity
links, should really be used. |
control |
control list for fitting - see gam.control . |
nb.iter |
Don't use! |
Essentially a GAM IRLS fitting loop, but with the mgcv
call followed by a call to
pcls
to fit subject to the constraints. Also, fitted values are reset to a small number if too small, to avoid negative numbers.
Returns fitted mopdel object.
Simon N. Wood snw@st-and.ac.uk
http://www.ruwpa.st-and.ac.uk/simon.html