R help - Apr 2004 - Problem with breakpoints (strucchange)

On Fri, 16 Apr 2004 13:21:13 -0400 kjetil at entelnet.bo wrote:
> Hola!
> 
> I am using package strucchange, and encounters the following:
> 
> >  bp <- breakpoints(diesel90  ~ regress -1, h=NULL)
> Error in La.chol2inv(x, size) : element (14, 14) is zero, so the 
> inverse cannot be computed
> 
> The obvious problems have been checked, that is, the model matrix is 
> of full rank. What can be causing this?
For segmenting the model each sub-model you are fitting has to have a
regressor matrix of full rank. Is `regress' a factor? If so, the minimal
segment size h has to be large enough that the corresponding
coefficients can be estimated in each (potential) segment.
> I can send some data if that can be of help.
If you cannot solve the problem, you can also contact me off-list.

hth,
Z
> Kjetil Halvorsen
> 
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Hola!

I am using package strucchange, and encounters the following:
>  bp <- breakpoints(diesel90  ~ regress -1, h=NULL)
Error in La.chol2inv(x, size) : element (14, 14) is zero, so the 
inverse cannot be computed

The obvious problems have been checked, that is, the model matrix is 
of full rank. What can be causing this?

I can send some data if that can be of help.

Kjetil Halvorsen