Displaying 20 results from an estimated 6000 matches similar to: "Please help on correlation matrix"
2009 Aug 16
2
bootstrapped correlation confint lower than -1 ?
Dear R users,
Does the results below make any sense? Can the the interval of the
correlation coefficient be between *-1.0185* and -0.8265 at 95%
confidence level?
Liviu
> library(boot)
> data(mtcars)
> with(mtcars, cor.test(mpg, wt, met="spearman"))
Spearman's rank correlation rho
data: mpg and wt
S = 10292, p-value = 1.488e-11
alternative hypothesis: true rho is not
2005 Dec 03
1
Correlation matrix from a vector of pairwise correlations
I've a vector of pairwise correlations in the order low-index element
precedes the high-index element, say:
corr(1,2)=0.1, corr(1,3)=0.2, corr(2,3)=0.3, corr(3,4)=0.4
How can I construct the corresponding correlation matrix?
I tried using the "combn"-function in "combinat" package:
library(combinat)
combn(c(0.1,0.2,0.3,0.4),2)
, but to no avail...
Thank you for your
2007 Aug 02
1
Multivariable correlation
Given a square matrix of variables X, is there any way to compute a multivariable correlation among all the variables in the array? It is possible to calculate the correlation of all pairs of variables in the array, but I want to know the correlation of all the variables taken together, i.e. for the matrix
X=x1 x2 x3
x4 x5 x6
x7 x8 x9
I don't want the pair-wise correlations
2008 Sep 02
1
correlation with boot
Hi R users,
I have one simple question but I really don't know why I can't get it work.
The data was adopted from Efron's An introduction to the bootstrap book.
> nlaw
LSAT GPA
[1,] 576 3.39
[2,] 635 3.30
[3,] 558 2.81
[4,] 578 3.03
[5,] 666 3.44
[6,] 580 3.07
[7,] 555 3.00
[8,] 661 3.43
[9,] 651 3.36
[10,] 605 3.13
[11,] 653 3.12
[12,] 575 2.74
2002 Dec 20
1
Printing correlation matrices (lm/glm)
Hi Folks,
I'm analysing some data which, in its simplest aspect,
has 3 factors A, B, C each at 2 levels.
If I do
lm1 <- lm(y ~ A*B)
say, and then
summary(lm1, corr=T)
I get the correlation matrix of the estimated coeffcients
with numerical values for the correlations (3 coeffs in this
case). Likewise with 'glm' instead of 'lm'.
However, if I do
lm2 <- lm(y ~
2009 Aug 24
2
robust method to obtain a correlation coeff?
Hi,
Being a R-newbie I am wondering how to calculate a correlation
coefficient (preferably with an associated p-value) for data like:
> d[,1]
[1] 25.5 25.3 25.1 NA 23.3 21.5 23.8 23.2 24.2 22.7 27.6 24.2 ...
> d[,2]
[1] 0.0 11.1 0.0 NA 0.0 10.1 10.6 9.5 0.0 57.9 0.0 0.0 ...
Apparently corr(d) from the boot-library fails with NAs in the data,
also cor.test cannot cope with a
2004 Jul 13
2
Is there a statistics that can summarize the correlation for more than two random variables?
Hi, R people,
I wonder if there is a statistics than can measure the correlation for more
than two random variables, instead of computing the correlation coefficient
matrix. If so, what R package should I use?
Right now I can only think of the mean of all pair-wise correlation
coefficients, e.g., (corr(x,y) + corr(x,z) + corr(y,z)) / 3 for three random
variables (x, y, z).
Thanks a
2010 Jun 08
1
Deleting duplicate values in a correlation matrix
I have a large correlation matrix that I'm trying to convert to a list of
every connection (edge) between every two nodes with its accompanying
correlation value (for Cytoscape). I figured out how to do this and to
remove the connections that nodes have to themselves but I can't figure out
how to get rid of the duplicate pairs (e.g. the edge b-a is a duplicate of
a-b).
2008 Mar 08
1
how to compute uncentered (pearson correlation) correlation efficiently
Hi,
Seeking suggestions to compute uncentered (pearson correlation) correlation
efficiently.
corr from stats library works on x and y columns. dist from amap library
works on x and y rows.
My data layout is slightly different such that row(i) of matrix x is
compared to row(i) of matrix y.
Thanks
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2006 Sep 06
1
Covariance/Correlation matrix for repeated measures data frame
All,
I have a repeated measures data frame and was wondering if the
covariance matrix can be
calculated via some created indexing or built-in R function.
Specifically, say there are 3 variables, where potassium concentration
is measured 6 times on each patient.
Patient number (discrete)
Time (1 to 6, discrete)
Potassium (continuous variable)
I want the covariance/correlation matrix for the
2007 May 08
2
statistics/correlation question NOT R question
This is not an R question but if anyone can help me, it's much
appreciated.
Suppose I have a series ( stationary ) y_t and a series x_t ( stationary
)and x_t has variance sigma^2_x and epsilon is normal
(0, sigma^2_epsilon )
and the two series have the relation
y_t = Beta*x_t + epsilon
My question is if there are particular values that sigma^2_x and
sigma^2_epsilon have to take in
2009 Mar 09
1
Zero distance error in corSpatial - correlation structure using lme
Hello,
I am having a problem specifying the correlation structure in lme which
leads to the error: Error in getCovariate.corSpatial(object, data =
data) : Cannot have zero distances in "corSpatial". I have specified a
grouping variable which is the only fix I could find by searching this
error on R-help.
ISee the below example. When my samples (tran) - which are transects
2011 Jan 30
1
Finding the correlation coefficient of two stocks
veepsirtt wrote:
>
> corr <- cor(s1,s2)
> Error in cor(s1, s2) : incompatible dimensions
>
>
Check lenghts of your series.
cor(c(1,2),c(1,2,3))
#Error in cor(c(1, 2), c(1, 2, 3)) : incompatible dimensions
Dieter
--
View this message in context: http://r.789695.n4.nabble.com/Finding-the-correlation-coefficient-of-two-stocks-tp3246992p3247042.html
Sent from the R help
2006 Jun 28
1
Simulate dichotomous correlation matrix
Newsgroup members,
Does anyone have a clever way to simulate a correlation matrix such that
each column contains dichotomous variables (0,1) and where each column
has different prevalence rates.
For instance, I would like to simulate the following correlation matrix:
> CORMAT[1:4,1:4]
PUREPT PTCUT2 PHQCUT2T ALCCUTT2
PUREPT 1.0000000 0.5141552 0.1913139 0.1917923
PTCUT2
2011 Jun 26
2
Ordering a matrix based on cluster no
Hi All
I have a symmetric matrix of genes ( 100x100 matrix). I also have a matrix
(100x2) of two columns where column 1 has the gene names and column 2 has
the cluster it belongs to (they are sorted and grouped based on the cluster
no).
I would like to order the rows and columns of the 100x 100 matrix such that
the first n genes correspond to cluster 1 and next n genes correspond to
cluster 2
2010 Nov 23
2
Calculating correlation
Hi guys
I have an input file with multiple columns and and rows.
Is it possible to calculate correlation of certain value of certain No (For
example x of S1 = 112) with all other values (for example start with x 112
corr a 3 of S1 = x-a 0.2 )
INPUT
*******
No S1 S2 S3 S4 Sn
a 3 4 45 34 23
x 112 0 12 23 0
b 0 1 23 12 1
n 0 1 0 1 1
2006 Oct 19
2
How to get multiple Correlation Coefficients
Hi
I have used a polycor package for categorical correlation coefficients.
I run the following script. But there were no results.
Could you tell me how to correct the script?
Thanks in advance,
vars <- names(sdi)
for (i in 1:length(vars)) {
for (j in 1:length(vars)) {
paste(vars[i]," and ", vars[j])
polychor(vars[i], vars[j])
# corr
}
}
--
Kum-Hoe Hwang, Ph.D.Phone :
2006 Sep 23
1
variance-covariance structure of random effects in lme
Dear R users,
I have a question about the patterned variance-covariance structure for the random effects in linear mixed effect model.
I am reading section 4.2.2 of "Mixed-Effects Models in S and S-Plus" by Jose Pinheiro and Douglas Bates.
There is an example of defining a compound symmetry variance-covariance structure for the random effects in a
split-plot experiment on varieties of
2011 Nov 29
3
Matrix for correlation
hi @ all,
I have problem with creating a matrix for a cor() function.
I try to use the cor() function on a matrix to test the correlation between
each value in a column.
Maybe like corr(x, method = xyz).
My x has two columns maybe like this:
MEDIA VALUE
Car 23
Train 26
Plane 25
Cab 22
Bike 15
.... and so on.
Now I want to calculate the correlation between Car and Train, Car
2010 Jul 07
1
ifelse statement
Hi, I am a newbie of R, and playing with the "ifelse" statement.
I have the following codes:
## first,
for(i in 1:3) {
for(j in 2:4) {
cor.temp <- cor(iris.allnum[,i], iris.allnum[,j])
if(i==1 & j==2) corr.iris <- cor.temp
else corr.iris <- c(corr.iris, cor.temp)
}
}
this code is working fine.
I also tried to perform the same thing in another way with "ifelse":