Re: [R] Dissimilarity matrix and number clusters determination

[Luisfo Chiroque via R-help]

Dear Michael,

Yes, AFAIK you are correctly reading the results.
You can print
elbow.obj$k
to obtain the optimal number of clusters, and ‘visually’ you can check it 
plotting the variance vs #clusters
plot(css.obj$k, css.obj$ev)

HTH

Best,
Luisfo Chiroque
PhD Student
IMDEA Networks Institute
http://fourier.networks.imdea.org/people/~luis_nunez/ 

> El 12 abr 2016, a las 4:30, Michael Artz  escribió:
> 
> Hi,
>  I already have a dissimilarity matrix and I am submitting the results to
> the elbow.obj method to get an optimal number of clusters.  Am I reading
> the below output correctly that I should have 17 clusters?
> 
> code:
> top150 <- sampleset[1:150,]
> {cluster1 <- daisy(top150
>   , metric = c("gower")
>   , stand = TRUE
>   , type = list(symm = 1))
> }
> 
> dist.obj <- dist(cluster1)
> hclust.obj <- hclust(dist.obj)
> css.obj <- css.hclust(dist.obj,hclust.obj)
> elbow.obj <- elbow.batch(css.obj)
> 
> [1] "A \"good\" k=17 (EV=0.80) is detected when the EV is no less than
> 0.8\nand the increment of EV is no more than 0.01 for a bigger k.\n"
> attr(,"class")
> 
>   [[alternative HTML version deleted]]
> 
> __
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> and provide commented, minimal, self-contained, reproducible code.


[[alternative HTML version deleted]]

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[R] Dissimilarity matrix and number clusters determination

[Michael Artz]

Hi,
  I already have a dissimilarity matrix and I am submitting the results to
the elbow.obj method to get an optimal number of clusters.  Am I reading
the below output correctly that I should have 17 clusters?

code:
top150 <- sampleset[1:150,]
{cluster1 <- daisy(top150
   , metric = c("gower")
   , stand = TRUE
   , type = list(symm = 1))
}

dist.obj <- dist(cluster1)
hclust.obj <- hclust(dist.obj)
css.obj <- css.hclust(dist.obj,hclust.obj)
elbow.obj <- elbow.batch(css.obj)

[1] "A \"good\" k=17 (EV=0.80) is detected when the EV is no less than
0.8\nand the increment of EV is no more than 0.01 for a bigger k.\n"
attr(,"class")

[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.