[R] CVnn2 + nnet question

[Prof Brian Ripley]

You are trying to fit a neural network with no connections.  That makes no 
sense unless skip=T (as on the page you are quoting).

On Mon, 14 Jun 2004, Manoj - Hachibushu Capital wrote:

> Hi,
> 	I am trying to determine the number of units in the hidden layer
> and the decay rate using the CVnn2 script found in MASS directory
> (reference: pg 348,MASS-4). 
> 
> 	The model that I am using is in the form of Y ~ X1 + X2 + X3...
> + X11 and the underlying data is time-series in nature.
> 
> 	I found the MASS and nnet package extremely useful (many thanks
> to the contributors). 

`contributors'?  Do see the DESCRIPTION file: it is hardly anonymous work.

> 	However I am getting an error while using the CVnn2
> function...it says 

You have not shown us the call you used, but the default arguments are
size = rep(6, 2), lambda = c(0.001, 0.01) so you have used non-default 
args without telling us what.

> Fold 1 
> Size = 0, decay = 0, inner fold 1 Error in nnet.default(x,y,w,....): No
> weights  to fit.
> 
> 	Obliviously I am doing something wrong but am not able to figure
> it out. 

Please do re-read the basic description of neural nets and nnet().

> Do I have pass any weights?  I am bit confused since the
> documentation of nnet suggests says "Wts: initial parameter vector. If
> missing chosen at Random". Has anybody faced the same error? I am using
> the latest R version on Linux box. 

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
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