Displaying 20 results from an estimated 20000 matches similar to: "weighted correlation coefficient"
2012 Feb 08
0
glm.fit and pearson's correlation coefficient
I did a linear correlation of data using glm.fit and stored the output in the
object "f":
f <- glm.fit(x, y, w)
I am intereseted in estimating the quality of the correlation. I am used to
do it using pearson correlation coefficient "r" or "r^2". Can I extract this
coefficient from the output of glm.fit?
Is there another number in the output of glm.fit that
2005 Sep 27
1
Simulate phi-coefficient (correlation between dichotomous vars)
Newsgroup members,
I appreciate the help on this topic.
David Duffy provided a solution (below) that was quite helpful, and came
close to what I needed. It did a great job creating two vectors of
dichotomous variables with a known correlation (what I referred to as a
phi-coefficient).
My situation is a bit more complicated and I'm not sure it is easily
solved. The problem is that I must
2010 Nov 29
1
weighted Spearman correlation coefficient
Hello,
I would be grateful if anybody can help me in finding an R function to
compute weighted Spearman correlation coefficient?
Kind regards,
Daniel
2011 Mar 20
1
Pearson correlation coefficient matrix with permutation test
Hello,
I found an interesting program on Pierre Legendre's webpage:
http://www.bio.umontreal.ca/casgrain/en/labo/corr_permute.html
With this program one can compute a "Pearson correlation coefficient matrix with permutation test".
This is exactly what I need as an R-package because so far I have only analyzed my data with the function cor(). However, I need additional
2004 Apr 10
1
confidential interval of correlation coefficient using bootstrap
I tried 2 methods to estimate C.I. of correlation coefficient of variables x and y:
> x <- c(44.4, 45.9, 41.9, 53.3, 44.7, 44.1, 50.7, 45.2, 60.1)
> y <- c( 2.6, 3.1, 2.5, 5.0, 3.6, 4.0, 5.2, 2.8, 3.8)
#METHOD 1: Pearson's
**********************************************************
> cor.test(x, y, method = "pearson", conf.level = 0.95)
Pearson's
2008 Dec 07
2
concordance correlation coefficient using R
Hi.
I have data which i would want to assess the degree of agreement
between two assays, e.g., to evaluate reproducibility or for
inter-rater reliability. I have used the Pearson product-moment
correlation coefficient. It looks good ranginging between 0.90 to
0.998. Though this looks good. I am told the Concordance correlation
coefficient will give a better picture of how reproducible the assay
2007 May 21
1
Sample correlation coefficient question NOT R question
This is a statistics question not an R question. When calculating the
sample correlation coefficient cor(x_t,y_t) between say
two variables, x_t and y_t t=1,.....n ( one can assume that the
variables are in time but I don't think this really matters
for the question ), does someone know where I can find any piece of
literature that says that each (x_j,y_j) pair has
To be independent from the
2010 Jan 14
0
Bootstrap for correlation coefficient
I have the following code:
## to check correlation between the simulated uniform data
x2 <- uni[,1] ; x2[1:10]
y2 <- uni[,2] ; y2[1:10]
result2 <- boot(cbind(x2,y2), f, 20)
# get 95% confidence interval
boot.ci(result2, type="bca")
cor.test(x2,y2, method="pearson", conf.level=0.95)
part of my data:
> x2 <- uni[,1] ; x2[1:10]
[1] 0.63933145 0.71677785
2010 Dec 06
5
Urgent Help with R calculation correlation coefficient
Hi,
I am trying to calculate correlation coefficient for gene expression data.
Tab delimited file looks like this
Id v1 v2 v3
df 56 90 45
gh 87 98 78
ty 89 78 67
I used this code
[code]
gse20437 <- read.csv("C:/Users//Desktop/data/GSE20437_matrix.txt",header =
TRUE, sep = ",", strip.white = TRUE)
gsecor <- cor(gse20437, method
2010 May 05
1
rcorr p-values for pearson's correlation coefficients
Hi! All,
To find co-expressed genes from a expression matrix of dimension (9275
X 569), I used rcorr function from library(Hmisc) to calculate pearson
correlation coefficient (PCC) and their corresponding p-values. From
the correlation matrix (9275 X 9275) and pvalue matrix (9275 X 9275)
obtained using rcorr function, I wanted to select those pairs whose
PCC's are above 0.8 cut-off and then
2008 Sep 30
0
calculating weighted correlation coefficients
Dear Help,
I'm trying to calculate a weighted correlation matrix from a data frame with
6 columns (variables) and 297 observations extracted from the regression.
The last column is a weight column which I want to apply.
$ model :'data.frame': 297 obs. of 6 variables:
..$ VAR1 : num [1:297] 5.21 9.82 8.08 0.33 8.7 6.82 3.94 4 0 5 ...
..$ VAR2 : num [1:297]
2008 Apr 05
2
pearson's correlation
Hello,
I used the function cor to calculate the pearson correlation coefficient between variables. However, the resulting values do not correspond to the outcome of my excel-calculations, for which I used the formula Cor(x,y)=Cov(x,y)/(SD(x)*SD(y))
So my question is: How does the function "cor" compute the pearson correlation coefficient?
Thank you in advance,
Ake Nauta
2009 May 26
2
(OT) Does pearson correlation assume bivariate normality of the data?
Dear all,
The other day I was reading this post [1] that slightly surprised me:
"To reject the null of no correlation, an hypothsis test based on the
normal distribution. If normality is not the base assumption your
working from then p-values, significance tests and conf. intervals
dont mean much (the value of the coefficient is not reliable) " (BOB
SAMOHYL).
To me this implied that in
2011 Apr 07
3
Correlation Matrix
Listers,
I have a question regarding correlation matrices. It is fairly straight
forward to build a correlation matrix of an entire data frame. I simply use
the command cor(MyDataFrame). However, what I would like to do is construct
a smaller correlation matrix using just three of the variable out of my data
set.
When I run this:
cor(MyDataFrame$variable1,
2009 Jan 12
3
polychoric correlation: issue with coefficient sign
Hello,
I am running polychoric correlations on a dataset composed of 12 ordinal and
binary variables (N =384), using the polycor package.
One of the association (between 2 dichotomous variables) is very high using
the 2-step estimate (0.933 when polychoric run only between the two
variables; but 0.801 when polychoric run on the 12 variables). The same
correlation run with ML estimate returns a
2002 Nov 21
1
Pearson's correlation coefficient?
How do I get non-squared correlation coefficient in some more
sensible way than
sqrt(summary(lm(y~x))$r.squared)?
Thanks
Matej
--
Matej Cepl, matej at ceplovi.cz,
Finger: 89EF 4BC6 288A BF43 1BAB 25C3 E09F EF25 D964 84AC
138 Highland Ave. #10, Somerville, Ma 02143, (617) 623-1488
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every time Congress meets
-- Will
2004 Sep 03
2
Standard correlation
Hi
Is there a function for computing the standard correlation coefficient
(not pearson) in R?
Thanks
Mick
2006 Jan 25
2
how to test robustness of correlation
Hi, there:
As you all know, correlation is not a very robust procedure. Sometimes
correlation could be driven by a few outliers. There are a few ways to
improve the robustness of correlation (pearson correlation), either by
outlier removal procedure, or resampling technique.
I am wondering if there is any R package or R code that have incorporated
outlier removal or resampling procedure in
2006 Sep 25
0
Sampling distribution of correlation estimations derived from robust MCD and MVE methods
Dear R users,
I am trying to use MCD and MVE methods in the analysis of functional imaging
(fMRI) data. But, before doing that, I want to understand the sampling
distribution of the correlation parameter given by MCD and MVE (cov.mcd$cor,
cov.mve$cor).
To this end, I conducted a simulation where in each of 100000 epochs, I
a. construct a matrix from two vectors, each containing 40 numbers
2006 Sep 25
0
[PlainText Attempt] Sampling distribution of correlation estimations derived from robust MCD and MVE methods
Dear R users,
I am trying to use MCD and MVE methods in the analysis of functional imaging
(fMRI) data. But, before doing that, I want to understand the sampling
distribution of the correlation parameter given by MCD and MVE (cov.mcd$cor,
cov.mve$cor).
To this end, I conducted a simulation where in each of 100000 epochs, I
a. construct a matrix from two vectors, each containing 40 numbers