[R] mgcv: lowest estimated degrees of freedom

[Julian Burgos]

Dear list,

I do apologize if these are basic questions.  I am fitting some GAM 
models using the mgcv package and following the model selection criteria 
proposed by Wood and Augustin (2002, Ecol. Model. 157, p. 157-177).  One 
criterion to decide if a term should be dropped from a model is if the 
estimated degrees of freedom (EDF) for the term are close to their lower 
limit.

What would be the minimum number of EDF's for
a) Univariate thin plate regression splines(TPRS) with shrinkage, i.e.  
s(...,bs="ts")
b) Bivariate tensor products of TPRS with shrinkage?

Thanks for any help,

Julian Burgos

-- 
Julian M. Burgos

Fisheries Acoustics Research Lab
School of Aquatic and Fishery Science
University of Washington

1122 NE Boat Street
Seattle, WA  98105 

Phone: 206-221-6864