[R] problem with "gl1ce" function from "lasso2" package

[Liviu Theodor Ene]

Hello, 

I encounter a problem when using the "gl1ce" function from "lasso2" package.

First, I tried something like:
etastart          <- log(mean(y))
fit.gl1ce.log   <- gl1ce(y~., data = xy, family = gaussian(log))
and nearly all the coefficients in "fit.gl1ce.log" were zero (except the intercept and one predictor out of 25), and no warnings were produced.

This is not what I expected, since the "glm" function with  "gaussian(log))" could fit a model using all the 25 predictors, and when using the " fit.l1ce" function:
fit.l1ce  <- l1ce(log(y)~., data = xy)
ca. 33% or the coefficients were set to zero, which is OK.

The problem with having too many zero-coefficients persists even when using the "gl1ce" with identity link: 
fit.gl1ce.id  <- gl1ce(y ~ . , data = xy, family = gaussian())
fit.gl1ce.id  <- gl1ce(log(y) ~ . , data = xy, family = gaussian())

I wonder what should I do more for getting a reasonable model with the "gl1ce" function.


Thanks,

Liviu

-------------------------------------------------------------------
Liviu Theodor Ene, PhD           
  
Researcher - Forest Inventory                                      
Norwegian University of Life Sciences     
Department of Ecology and                                                             
Natural Resource Management 
                
Pb. 5003, 1500 - INA, 1432, Ås, Norway      
                                                                                                  
Tel: +47 - 64 96 57 66
Fax: +47 - 64 96 58 01

www.umb.no
www.forestinventory.no