Displaying 20 results from an estimated 50000 matches similar to: "choosing the correct number of clusters using NbClust"
2012 Aug 22
0
choosing the correct number of clusters usinf NbClust
I am attempting to use NbClust to examine different indices to determine
the number of clusters. The code appears to be working and I am getting
results. However, I have noticed that each time I run it I may get
different answers. For example looking at the DB index one run
recommended 6 clusters while the next 5 - the code is exactly the same.
I assume there is some randomization that I
2012 Aug 12
0
Index Values in NbClust
Dear All,i applied "NbClust", to my data to find optimum number of clusters, and got following resultsNow, i don't know how to read these results. more precisely, i would like to know, how to see which method is more precise for my data considering these index values.your help is needed...thanks in advance
Eliza Botto
> dput(Eliza)structure(list(All.index = structure(c(2, 3, 4, 5,
2012 Sep 17
1
self defined distance matrix in NbClust
i m using a package NbClust for cluster analysis. in the following algorithm
->NbClust(m, diss="NULL", distance = "euclidean", min.nc=2, max.nc=15, method = "ward", index = "all", alphaBeale = 0.1)
i want to define my own dissimilarity matrix of dimension 38*38. my original data "m" is a matrix of 365*38. whenever i define my own dissimilarity
2016 Apr 12
1
Dissimilarity matrix and number clusters determination
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
2017 Jan 16
4
Error K-MEDIAS, paquete NbClust windows 10, 64 bits
Buenos dias, desde hace algunos dias estoy realizando un trabajo,mi computadora es una DELL, windows 10 64 bits, 8G de RAM y disco de estado solido, estoy procesando 29000 filas y 23 columnas, mi codigo es este:
nb <- NbClust(datos.scaled, distance = "euclidean", min.nc = 2,
#max.nc = 10, method = "complete", index ="all")
.
y mi error es este:
Error:
2003 Apr 24
1
AW: estimating number of clusters ("Null or more")
Dear Christian,
first of all thank you for your answer. I am going to parse through
the pages you told me. Meanwhile I'd like to note that probably it
is a good idea to put 2-3 lines of R-code demonstrating such a
simple needs somnewhere in docs of `cluster' package. E.g.
x<-rnorm(500)
... # output means we have rather 1 claster
x<-c(rnorm(500), rnorm(500)+5)
2005 May 17
4
Finding the right number of clusters
SAS has something called the "cubic criterion" cutoff for finding the
most appropriate number of clusters. Does R have anything that would
replicate that? I've been searching the lists and can't seem to find
anything that would point me in the right direction.
Thank in advance,
Philip Bermingham
2006 Feb 05
3
Cluster Analysis - Number of Clusters
Hello,
I'm playing around with cluster analysis, and am looking for methods to
select the number of clusters. I am aware of methods based on a 'pseudo
F' or a 'pseudo T^2'. Are there packages in R that will generate these
statistics, and/or other statistics to aid in cluster number selection?
Thanks,
John.
--
2003 Apr 24
1
estimating number of clusters ("Null or more")
Hi all,
once more about the old subj :-)
My data has too much various distribution families and for every
particular experiment
I need just to decide whether the data is "quite homogeneous" or it has
two or more
clusters. I've revisited the following libraries:
amap, clust, cclust, mclust, multiv, normix, survey.
And I didn't find any ready-to-use general
2009 Jun 11
1
Cluster analysis, defining center seeds or number of clusters
I use kmeans to classify spectral events in high and low 1/3 octave bands:
#Do cluster analysis
CyclA<-data.frame(LlowA,LhghA)
CntrA<-matrix(c(0.9,0.8,0.8,0.75,0.65,0.65), nrow = 3, ncol=2, byrow=TRUE)
ClstA<-kmeans(CyclA,centers=CntrA,nstart=50,algorithm="MacQueen")
This works well when the actual data shows 1,2 or 3 groups that are not
"too close" in a cross plot.
2012 Feb 23
2
Advice on exploration of sub-clusters in hierarchical dendrogram
Dear R user,
I am a biochemist/bioinformatician, at the moment working on protein
clusterings by conformation similarity.
I only started seriously working with R about a couple of months ago.
I have been able so far to read my way through tutorials and set-up my
hierarchical clusterings. My problem is that I cannot find a way to obtain
information on the rooting of specific nodes, i.e. of
2008 Oct 30
1
PAM: how to get the best number of clusters
I have a pretty big similarity matrix (2870x2870). I will produce even
bigger ones soon.
I am using PAM to generate clusters.
The desired number of output clusters is a PAM input parameter.
I do not know a-priopri what is the best clusters layout .
I resorted to the silhouette test. It takes forever as I have to run PAM
with all possible
numbers of clusters.
I wonder whether there is some faster
2008 Sep 30
1
CLARA and determining the right number of clusters
Hi everyone
I have a question about clustering. I've managed using CLARA to get a
clustering analysis of a large data set. But now I want to find which is the
right number of clusters.
The clara.object gives some information like the ratio between maximal and
minimal dissimilarity that says (maybe if lower than 1??) if a cluster is
well-separated from the other. I've also read something
2003 Jun 09
1
estimate the number of clusters
Dear All,
I am using Silhouette to estimate the number of clusters in a microarray
dataset.
Initially, I used the iris data to test my piece of code as follows:
library(cluster)
data(iris)
mydata<-iris[,1:4]
maxk<-15 # at most 15 clusters
myindex<-rep(0,maxk) # hold the si values for each k clusters
mdist<-1-cor(t(mydata)) #dissimlarity
2003 Apr 24
0
AW: AW: estimating number of clusters ("Null or more")
> > It would be nice not only for me.
>
> I agree totally.
If you belong to R-contributors group then thanks a lot
in advance!
> The problem is that you have to formalize what a cluster is,
> and this is not a well defined notion.
> It has different meanings in different applications.
you are right if one follows the idea of full formalization of
the notion it
2007 Jul 18
0
Ideal number of clusters using the Fanny algorithm
Hello,
Could someone please let me know the procedure for determining the 'best'
solution with regards to the number of clusters using the Fanny algorithm
for computing fuzzy clusters? The function requires a specification of the
number of clusters a priori, but I am interested in determining what number
of clusters would result in the ideal fit with the data. Any
help/advice/pointers to
2006 Apr 30
1
Number of Clusters
Dear R users, I am interested in clustering in R. In SAS we have some criteria for determining the number of clusters using the PROC CLUSTER procedure, which are "CCC" cubic clustering criterion (Sarl 1981), Psuedo F (PSF), and Psuedo T square (PST). My question is do thsese criterion exists in R, I tried to search and got one hit (BIC) in Mclust, which I am aware of, any input is
2006 Apr 19
1
determining optimal # of clusters for a given dataset (e.g. between 2 and K)
Hi:
I'm clustering a microarray dataset with a large # of samples. I would like your opinion on the best way to automatically determine the optimal # of clusters. Currently I am using the "cluster" package, clustering with "clara", examining the average silhouette width at various numbers of clusters. I'd like opinions on whether any newer packages offer
2010 Aug 06
1
Grouping clusters from dendrograms
Hi,
I have produced a dendrogram of categorical data in R using the hclust
function, although the input was a dissimilarity matrix produced in SAS, as
I have defined my own distances.
The dendrogram is fine and I can view and use this. However, I was wondering
if there is a method by which I can find out the optimal place to place
groups, rather than relying on my visual analysis? I don't
2006 Apr 15
0
clustering genes / automatically determining # of clusters
Hi:
I'm clustering a microarray dataset with a large # of samples. I would like your opinion on the best way to automatically determine the optimal # of clusters. Currently I am using the "cluster" package, clustering with "clara", examining the average silhouette width at various numbers of clusters. I'd like opinions on whether any newer packages offer