Displaying 20 results from an estimated 2000 matches similar to: "Otpmial initial centroid in kmeans"
2016 Aug 19
2
KMeans - Evaluation Results
On 18 Aug 2016, at 23:59, Richhiey Thomas <richhiey.thomas at gmail.com> wrote:
> I've currently added a few classes which don't really belong to the public API (currently) into private headers and used PIMPL with the Cluster class.
I'm having difficulty reading your changes, because you aren't keeping to one complete change per commit. So for instance you've added a
2005 Mar 31
2
Using kmeans given cluster centroids and data with NAs
Hello,
I have used the functions agnes and cutree to cluster my data (4977
objects x 22 variables) into 8 clusters. I would like to refine the
solution using a k-means or similar algorithm, setting the initial
cluster centres as the group means from agnes. However my data matrix
has NA's in it and the function kmeans does not appear to accept this?
> dim(centres)
[1] 8 22
> dim(data)
2016 Aug 15
2
KMeans - Evaluation Results
Hello,
I've recently finished with an implementation of KMeans with two
initialization techniques, random initialization and KMeans++. I would like
to share my findings after evaluating the same.
I have tested this implementation of KMeans with a BBC news article
dataset. I am currently working on evaluating the same with FIRE datasets.
Currently, clustering more than 500 documents
2016 Jul 26
3
K MEANS clustering
Hello,
I've been working on the KMeans clustering algorithm recently and since the
past week, I have been stuck on a problem which I'm not able to find a
solution to.
Since we are representing documents as Tf-idf vectors, they are really
sparse vectors (a usual corpus can have around 5000 terms). So it gets
really difficult to represent these sparse vectors in a way that would be
2004 May 28
6
distance in the function kmeans
Hi,
I want to know which distance is using in the function kmeans
and if we can change this distance.
Indeed, in the function pam, we can put a distance matrix in
parameter (by the line "pam<-pam(dist(matrixdata),k=7)" ) but
we can't do it in the function kmeans, we have to put the
matrix of data directly ...
Thanks in advance,
Nicolas BOUGET
2016 Aug 18
3
KMeans - Evaluation Results
>
>
>
> Actually, you're doing something slightly unusual there: making the
> internal member public. Protected would be better, and private is I think
> most usual; library clients aren't going to have access to the Internal
> class declaration, so they can't call things on it. This means it's
> actually difficult right now to subclass Feature.
>
> I
2016 Aug 17
2
KMeans - Evaluation Results
On Wed, Aug 17, 2016 at 7:23 PM, James Aylett <james-xapian at tartarus.org>
wrote:
> >> How long does 200?300 documents take to cluster? How does it grow as
> more documents are included in the MSet? We'd expect an MSet of 1000
> documents to take longer to cluster than one with 100, but the important
> thing is _how_ the time increases as the number of documents
2006 Aug 07
5
kmeans and incom,plete distance matrix concern
Hi there
I have been using R to perform kmeans on a dataset. The data is fed in using read.table and then a matrix (x) is created
i.e:
[
mat <- matrix(0, nlevels(DF$V1), nlevels(DF$V2),
dimnames = list(levels(DF$V1), levels(DF$V2)))
mat[cbind(DF$V1, DF$V2)] <- DF$V3
This matrix is then taken and a distance matrix (y) created using dist() before performing the kmeans clustering.
My query
2008 Jun 18
3
Cluster on both categorical and numerical data
Hello there. Is there any function in R that can do cluster on a set of
data that has both categorical and numerical variables? thanks.
siangli
2009 Feb 05
1
Does the "labpt" object in the Polygons-class represent the centroid of the polygon
Hello,
I need to calculate the centroids of some spatial polygons that I have
placed into a Polygons-class object. Is the labeling point in the
Polygons-class the centroid of the polygon?
Thank you for your help.
2006 Mar 25
2
pairwise combinatons of variables
Dear WizaRds,
although this might be a trivial question to the community, I was unable to
find anything solving my problem in the help files on CRAN. Please help.
Suppose I have 4 variables and want to use all possible combinations:
1,2
1,3
1,4
2,3
2,4
3,4
for a further kmeans partitioning.
I tried permutations() of package e1071, but this is not what I need. Thank you
for your help and
2006 Jul 09
2
distance in kmeans algorithm?
Hello.
Is it possible to choose the distance in the kmeans algorithm?
I have m vectors of n components and I want to cluster them using kmeans
algorithm but I want to use the Mahalanobis distance or another distance.
How can I do it in R?
If I use kmeans, I have no option to choose the distance.
Thanks in advance,
Arnau.
2009 Dec 10
1
question about centroid-linkage (cluster analysis)
Dear R community,
I would be greatful if somebody could shed light on the following.
I have created a set of 6 points to check how centroid
agglomeration works in cluster analysis:
> Y <- data.frame(x=c(-1,1,1,-1,10,12),y=c(1,1,-1,-1,0,0))
It is quite intuitive to understand that the last clusters to be joined will be
{1,2,3,4} with {5,6}. Now, the centroid for the first cluster has
2008 Oct 15
1
Forecasting using ARIMAX
Dear R-helpers,
I would appreicate if someone can help me on the transfer parameter in ARIMAX and also see what I am doing is correct.
I am using ARIMAX with 2 Exogeneous Variables and 10 years data are as follows:
DepVar Period, depVar, IndepVar1 Period, indepVar1, IndepVar2 Period, indepVar2
Jan 1998,708,Jan 1998,495,Jan 1998,245.490
Feb 1998,670,Feb 1998,421.25,Feb 1998,288.170
Mar
2012 Nov 18
1
centroid of hclust
Dear UseRs,i want to find centroid of clusters, which i generated by hclust. Is there a way doing that? i took mean to elements in each cluster to get centroid but i am not sure if i am right?
thanks in advanceeliza
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2008 Jun 02
1
LDA and centroids
Hello,
I have carried out an lda analysis using the lda function of MASS
package. I have plotted the LD1xLD2 to represent the data. Now I would
like to get the centroids for each group of data and plot it on the
LD1xLD2 graph. How can I get the centroid value from the lda object?
Best,
Dani
--
Daniel Valverde Saub?
Grup de Biologia Molecular de Llevats
Facultat de Veterin?ria de la
2008 Jul 21
2
CART and CHAID
Can I say that RPART is a modified algo of CART and PARTY a modified of
CHAID?
Thanks.
----
Chua Siang Li
Consultant - Operations Research
Acceval Pte Ltd
Tel: 6297 8740
Email: siang.li.chua at acceval-intl.com
Website: www.acceval-intl.com
This message and any attachments (the "message"...{{dropped:12}}
2008 Jul 22
2
rpart$where and predict.rpart
Hello there. I have fitted a rpart model.
> rpartModel <- rpart(y~., data=data.frame(y=y,x=x),method="class", ....)
and can use rpart$where to find out the terminal nodes that each
observations belongs.
Now, I have a set of new data and used predict.rpart which seems to give
only the predicted value with no information similar to rpart$where.
May I know how
2012 Oct 21
1
Linear discriminant function analysis based median as group centroid and nonparametric scale estimators???
Dear All,
I am using a specific approach for my master thesis. In essence, a
supervised reclassification is used as an intermediate step to find chemical
parameters which are able to reclassify defined groups. These variables will
be used in a next step where location and scale estimators of the groups are
important. Traditionally linear discriminant analysis is used for
reclassification which
2011 Apr 27
1
centroid representation and MANOVA
hi all.
I have a matrix of data with 5 different groups and 20 individual
response per group, and about 12 variables collected for each. I want to
represent the result in a 2D plot. PCA is not so good because the
difference between the groups is not obvious. I have seen, in a recent
paper, people doing a MANOVA and representing it in a centroid plot
(they used Matlab to do it).
I would like