my major is bioinformatics, and i'm trying to cluster ( agglomerate the closest pari of observations ) in R. i have already got my own similarities metric, but do not know how to clust it based on similarities instead of dissimilarities. since the help document of hierclust mentions the parameter "sim", which seems good to me, but it doesn't appear in the code of hierclust() function again? and no sample about it. so could anybody please help me as author? thanks in advance xinan yang xinan@molgen.mpg.de
Martin Maechler
2004-Jun-10 09:30 UTC
[Rd] question about similarities cluster using hierclust
Hmm,
why on earth are you using hierclust() from the ORPHANED package
'multiv', when there's hclust() in the core 'stats'
package
and 'agnes' in the recommended 'cluster' package ?
To your question "similarities -> dissimilarities"
the textbooks all deal with this.
Assuming similarities s_ij in [0,1] {which you can get by scaling},
things mentioned are
e.g.,
d_ij := 1 - s_ij
d_ij := sqrt(1 - (s_ij)^2)
also d_ij := sqrt(1 - s_ij)
but really, in your situation where you're defining your
similarities yourself, you probably should rather think about
defining your dissimilarities yourself *directly* {i.e. not via
the above formulae}.
Martin Maechler
>>>>> "Xinan" == Xinan Yang <xinan@molgen.mpg.de>
>>>>> on Thu, 10 Jun 2004 09:04:05 +0200 writes:
Xinan> my major is bioinformatics, and i'm trying to cluster (
agglomerate
Xinan> the closest pari of observations ) in R.
Xinan> i have already got my own similarities metric, but do not know how
to
Xinan> clust it based on similarities instead of dissimilarities.
Xinan> since the help document of hierclust mentions the parameter
"sim",
Xinan> which seems good to me, but it doesn't appear in the code of
Xinan> hierclust() function again? and no sample about it. so could
anybody
Xinan> please help me as author?
Xinan> thanks in advance
Xinan> xinan yang
Xinan> xinan@molgen.mpg.de