[R] compositional data: percent values sum up to 1

[Spencer Graves]

What are you trying to do?  What I would do with this depends on many 
factors.

spencer graves

Christoph Lehmann wrote:
> again, under another subject:
> sorry, maybe an all too trivial question. But we have power data from J
> frequency spectra and to have the same range for the data of all our
> subjects, we just transformed them into % values, pseudo-code:
> 
> power[i,j]=power[i,j]/sum(power[i,1:J])
> 
> of course, now we have a perfect linear relationship in our x design-matrix,
> since all power-values for each subject sum up to 1.
> 
> How shall we solve this problem: just eliminate one column of x, or
> introduce a restriction which says exactly that our power data sum up to
> 1 for each subject?
> 
> Thanks a lot
> 
> Christoph