Displaying 20 results from an estimated 3000 matches similar to: "more clustering questions"
2005 Jul 20
4
poisson fit for histogram
I haven't been an R lister for a bit, but I hope to enlist someone's
help here. I think this is a simple question, so I hope the answer
is not much trouble. Can you please respond directly to this email
address in addition to the list (if responding to the list is
warranted)?
I have a histogram and I want to see if the data fit a Poisson
distribution. How do I do this? It is
2004 Dec 13
1
UPGMA
R-help folks:
Thanks in the past for your help. I have another question that I hope
has a simple answer. I have searched the R home pages and the R-help
archives with no hits. How can I cluster data in R using UPGMA?
I am not subscribed to the list (can't keep up with all the traffic!),
so I would appreciate it if you could email directly to me (or to the
list and to me).
Thanks,
Tom
2004 Dec 08
2
similarity matrix conversion to dissimilarity
I have a matrix of similarity scores that I want to convert into a
matrix of dissimilarity scores so that I can apply some clustering
methods to the data. That is, high values in my matrix signify
similarity and low values (zero being the lowest) signify no
similarity. What functions/options in R or its packages are available
for making this kind of transformation of a matrix?
2004 Feb 26
2
Multidimensional scaling and distance matrices
Dear All,
I am in the somewhat unfortunate position of having to reproduce the
results previously obtained from (non-metric?) MDS on a "kinship" matrix
using Statistica. A kinship matrix measures affinity between groups, and
has its maximum values on the diagonal.
Apparently, starting with a nxn kinship matrix, all it was needed to do
was to feed it to Statistica flagging that the
2006 Apr 19
3
isoMDS and 0 distances
Hi,
I'm trying to do a non-metric multidimensional scaling using isoMDS.
However, I have some '0' distances in my data, and I'm not sure how to
deal with them. I'd rather not drop rows from the original data, as I am
comparing several datasets (morphology and molecular data) for the same
individuals, and it's interesting to see how much morphological
variation can be
2002 Feb 15
1
cmdscale k=1
In applying multidimensional scaling, it seems to me that sometimes the
underlying dimensionality of the matrix is 1. However I found a case
where cmdscale failed when I tried k=1. Here it is:
m<-matrix(
c(.5,.81,.23,.47,.61,
.19,.5,.06,.17,.28,
.77,.94,.5,.74,.85,
.53,.83,.26,.5,.64,
.39,.72,.15,.36,.5),
nrow=5)
# BTW I think cmdscale uses only the lower triangle--how to enter only
# that
2014 Nov 06
1
limit of cmdscale function
Hi
We have a few questions regarding the use of the "isoMDS" function.
When we run "isoMDS" function using 60,000 x 60,000 data matrix,
we get the following error message:
------------------------------------
cmdscale(d, k) : invalid value of 'n'
Calls: isoMDS -> cmdscale
------------------------------------
We checked the source code of "cmdscale" and
2005 Sep 12
4
Document clustering for R
I'm working on a project related to document clustering. I know that R
has clustering algorithms such as clara, but only supports two distance
metrics: euclidian and manhattan, which are not very useful for
clustering documents. I was wondering how easy it would be to extend the
clustering package in R to support other distance metrics, such as
cosine distance, or if there was an API for
2007 Jun 14
2
Difference between prcomp and cmdscale
I'm looking for someone to explain the difference between these
procedures. The function prcomp() does principal components anaylsis,
and the function cmdscale() does classical multi-dimensional scaling
(also called principal coordinates analysis).
My confusion stems from the fact that they give very similar results:
my.d <- matrix(rnorm(50), ncol=5)
rownames(my.d) <-
2002 Dec 19
1
newbie question on dist
hi,
i have just begun using R, so please bear with me.
i am trying to use cmdscale and display the result. i read the data
using read.table(), calculate the proximity matrix using dist() and
the display the result using the cmdscale(). this is very fine.
in addition, i want the display to distinguish between two classes
of records in my data. i have my data records marked as "1" or
2013 Apr 26
1
prcomp( and cmdscale( not equivalent?
Hello,
I have a dilemma that I'm hoping the R gurus will be able to help resolve.
For background:
My data is in the form of a (dis)similarity matrix created from taking the
inverse of normalized reaction times. That is, each cell of the matrix
represents how long it took to distinguish two stimuli from one another-- a
square matrix of 45X45 where the diagonal values are all zero (since this
2002 Jan 10
1
Size of type double in object type dist (PR#1255)
The following problem occurs in R 1.4.0 and 1.3.1 for Windows95,
but not in R 1.2.0 for Windows95.
The problem does not occur in R 1.4.0 for Linux PC, Linux Alpha
and HP-UX.
Sometimes, the type of 'Size' of an object of type 'dist'
changes from integer into double. Running cmdscale on such a
'dist' object gives invalid results.
I don't know what should be considered
2005 Nov 04
1
Stress in multidimensional scaling
Hello,
We are trying to find a function to compute "stress" in our
multidimensional scaling analysis of a dissimilarity matrix. We've used
"dist()" to create the matrix and "cmdscale()" for the scaling. In order
to determine the number of dimensions we would like to plot stress vs.
dimensions. However, we cannot find a pre-made command. It seems that
other
2007 Jul 23
2
cmdscale question
Hi.
I know matrices that use distances between places works fine when using
cmdscale. However, what about matricies such as:
A B C D E
A 0 1 23 12 9
B 1 0 10 12 3
C 23 10 0 23 4
D 12 12 23 0 21
E 9 3 4 21 0
i.e. matrices which do not represent physical distances between places (as
they would not make sense for real distances such as the one above)
2001 Jul 17
2
cmdscale in package mva (PR#1027)
Full_Name: Laurent Gautier
Version: 1.3.0-patched
OS: IRIX 6.5
Submission from: (NULL) (130.225.67.199)
Hello,
The function La.eigen, called by cmdscale in the package mva behaves an
unexplicable way (for me).
The following lines show what happened.
I tried the very same on linux, and it worked fine.
>a <- matrix(c(1,2,3,2),3,3)
>a
[,1] [,2] [,3]
[1,] 1 2 3
[2,]
2018 Feb 07
2
add geo-replication "passive" node after node replacement
Hi all,
i had a replica 2 gluster 3.12 between S1 and S2 (1 brick per node)
geo-replicated to S5 where both S1 and S2 were visible in the
geo-replication status and S2 "active" while S1 "passive".
I had to replace S1 with S3, so I did an
"add-brick replica 3 S3"
and then
"remove-brick replica 2 S1".
Now I have again a replica 2 gluster between S3 and S2
2008 Feb 20
1
Stress with MDS
Hi,
I am looking for the best multidimensional configuration for my data (47*47
distance matrix).
I ve tried classical metric (cmdscale) and non metric MDS (isoMDS, nmds)
but it is now difficult to choose the best solution because of the
uncertainties in the definitions of the "stress" function.
So, same problem, several questions :
1. Statistical consideration : With
2001 Oct 12
1
MASS: isoMDS and sammon
If tbl is an object of class 'dist', you can do this:
a <- sammon(tbl, k=3)
But you can't do this:
b <- isoMDS(tbl, k=3)
Wouldn't it be sensible to have identical interfaces to sammon()
and isoMDS() ?
I think all that would be needed is to change this:
isoMDS <- function(d, y=cmdscale(d, 2), maxit=50, trace=TRUE)
{
...into this:
isoMDS <-
2017 Feb 07
2
[PATCH] Optimize silk_warped_autocorrelation_FIX() for ARM NEON
This is a great idea. But the order (psEncC->shapingLPCOrder) can be
configured to 12, 14, 16, 20 and 24 according to complexity parameter.
It's hard to get a universal function to handle all these orders
efficiently. Any suggestions?
Thanks,
Linfeng
On Mon, Feb 6, 2017 at 12:40 PM, Jean-Marc Valin <jmvalin at jmvalin.ca> wrote:
> Hi Linfeng,
>
> On 06/02/17 02:51 PM,
2006 Jun 08
7
Wrong reported free space over NFS
NFS server (b39):
bash-3.00# zfs get quota nfs-s5-s8/d5201 nfs-s5-p0/d5110
NAME PROPERTY VALUE SOURCE
nfs-s5-p0/d5110 quota 600G local
nfs-s5-s8/d5201 quota 600G local
bash-3.00#
bash-3.00# df -h | egrep "d5201|d5110"
nfs-s5-p0/d5110 600G 527G 73G 88% /nfs-s5-p0/d5110