Displaying 20 results from an estimated 9000 matches similar to: "the way to look at all the codings of any functions"
2008 Jan 02
2
strange behavior of cor() with pairwise.complete.obs
Hi all,
I'm not quite sure if this is a feature or a bug or if I just fail to understand
the documentation:
If I use cor() with pairwise.complete.obs and method=pearson, the result is a
scalar:
->cor(c(1,2,3),c(3,4,6),use="pairwise.complete.obs",method="pearson")
[1] 0.9819805
The documentation says that
" '"pairwise.complete.obs"' only
2008 Apr 01
1
SEM with a categorical predictor variable
Hi,
we are trying to do structural equation modelling on R. However, one of our
predictor variables is categorical (smoker/nonsmoker). Now, if we want to
run the sem() command (from the sem library), we need to specify a
covariance matrix (cov). However, Pearson's correlation does not work on the
dichotomous variable, so instead we produced a covariance matrix using the
Spearman's (or
2005 Feb 13
1
Bug in cor function (PR#7689)
I can't hardly accept the result of cor function with
pairwize.colplete.obs or complete.obs
insert print statements in cor function,
+ if (method != "pearson") {
+ Rank <- function(u) if (is.matrix(u))
+ apply(u, 2, rank, na.last = "keep")
+ else rank(u, na.last = "keep")
+ x <- Rank(x)
+
2012 Mar 07
2
how to see inbuilt function(cor.test) & how to get p-value from t-value(test of significance) ?
i can see source code of function
> cor
function (x, y = NULL, use = "everything", method = c("pearson",
"kendall", "spearman"))
{
na.method <- pmatch(use, c("all.obs", "complete.obs",
"pairwise.complete.obs",
"everything", "na.or.complete"))
2008 Nov 21
1
Bug in Kendall for n<4?
> library(Kendall)
> Kendall(1:3,1:3)
WARNING: Error exit, tauk2. IFAULT = 12 <<<<<<
tau = 1, 2-sided pvalue =1
I believe Kendall tau is well-defined for this case and the reported
value is correct; isn't it a bug to give a warning? (And if, e.g.,
the pvalue is not well-defined in this case, wouldn't it be better to
return NA or NaN or something?) Also,
2007 Oct 25
2
Novice programing question
Hi all,
I apologize for the ignorance implicit in this question, but I'm
having a hard time figuring out how R functions work. For example, if
I wanted to write a function to compute a variance, I would do
something like
>my.var <- function(x) (sum(((x-mean(x)))^2))/(length(((x-mean(x)))
^2)-1)
And this seems to work, e.g.,
> my.var(V1)
[1] 116.1
> var(V1)
[1] 116.1
2009 Dec 13
2
O(N log N) Kendall Tau
I've noticed that the implementation of Kendall's Tau in R is O(N^2).
The following reference describes how it can be done in O(N log N):
A Computer Method for Calculating Kendall's Tau with Ungrouped Data
William R. Knight
Journal of the American Statistical Association, Vol. 61, No. 314, Part
1 (Jun., 1966), pp. 436-439
http://www.jstor.org/pss/2282833
I'm interested in
2003 Nov 19
1
Specifying arguements in user defined functions
Dear R subscribees,
First, I am new to R and I apologize if the question is naive. I am trying to
find out where arguments specifications
can be found. For example, the code below (at the very bottom of
this email) contains the argument 'digits' in the function 'lin' which
printout my output to the 3rd decimal place. Somebody showed me the
'digits' argument, but did
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
2007 Dec 03
1
cor(data.frame) infelicities
In using cor(data.frame), it is annoying that you have to explicitly
filter out non-numeric columns, and when you don't, the error message
is misleading:
> cor(iris)
Error in cor(iris) : missing observations in cov/cor
In addition: Warning message:
In cor(iris) : NAs introduced by coercion
It would be nicer if stats:::cor() did the equivalent *itself* of the
following for a data.frame:
2003 Jun 17
2
outlier
Hi,
I want to calculate the R-squared between two variables. Can you advice me how to identify and remove the outliers before performing R-squared calculation?
Thanks,
Kan
---------------------------------
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[[alternate HTML version deleted]]
2013 Feb 28
1
PCA with spearman and kendall correlations
Hello,
I would like to do a PCA with dudi.pca or PCA, but also with the use of Spearman or Kendall correlations
Is it possible ?
Otherwise, how can I do, according to you ?
Thanking you in advance
Eric Bourgade
RTE
France
[[alternative HTML version deleted]]
2005 Aug 18
2
kendall tau correlation test for ties: Potential error (PR#8076)
Full_Name: Dirk Koschuetzki
Version: 2.1.1
OS: source code
Submission from: (NULL) (194.94.136.34)
Hello,
>From the source code (R-2.1.1, file: .../R-2.1.1/src/library/stats/R/)
******************************
cor.test.default <-
function(x, y, alternative = c("two.sided", "less", "greater"),
method = c("pearson", "kendall",
2004 May 24
1
bug in cor (..., use= ...)?
Dear R users,
I have not found anything on this in the archives. Does anyone know whehther
the parameter use= is not functioning in cor or enlighten me what it is
supposed to do?
My R version is "R version 1.8.1, 2003-11-21" on Windows 2000. I am hoping
to be able to update to 1.9.1 as soon as it has appeared (we are not allowed
here to install software on our own and thus I am trying
2004 Mar 03
1
cor(..., method="spearman") or cor(..., method="kendall") (PR#6641)
Dear R maintainers,
R is great. Now that I have that out of the way, I believe I have
encountered a bug, or at least an inconsistency, in how Spearman and
Kendall rank correlations are handled. Specifically, cor() and
cor.test() do not produce the same answer when the data contain NAs.
cor() treats the NAs as data, while cor.test() eliminates them. The
option
use="complete.obs" has
2004 Oct 14
1
correlating between two vectors of numbers
Hi, R!
Question1:
I am trying to correlate two vectors of numbers (two columns of microarray
signal values) by using the non-parametric Spearman's rank correlation
coefficient rho:
> cor.test(V2.Signal,V3.Signal,method="spearman")
but I get the error message:
Error in if (q > (n^3 - n)/6) pspearman(q - 1, n, lower.tail = FALSE) else
pspearman(q, :
missing value
2005 Aug 13
1
R/S-Plus/SAS yield different results for Kendall-tau and Spearman nonparametric regression
Colleagues,
I ran some nonparametric regressions in R (run in RedHat Linux), then
a colleague repeated the analyses in SAS. When we obtained different
results, I tested S-Plus (same Linux box). And, got yet different
results. I replicated the results with a small dataset:
DATA:
37.5
23
37.5
13
25
16
25
12
100
15
12.5
19
50
20
100
13
100
10
100
10
100
16
50
10
87.5
2010 Feb 08
2
Incorrect Kendall's tau for ordered variables (PR#14207)
Full_Name: Marek Ancukiewicz
Version: 2.10.1
OS: Linux
Submission from: (NULL) (74.0.49.2)
Both cor() and cor.test() incorrectly handle ordered variables with
method="kendall", cor() incorrectly handles ordered variables for
method="spearman" (method="person" always works correctly, while
method="spearman" works for cor.test, but not for cor()).
In
2004 Oct 22
1
cor, cov, method "pairwise.complete.obs"
Hi UseRs,
I don't want to die beeing idiot...
I dont understand the different results between:
cor() and cov2cov(cov()).
See this little example:
> x=matrix(c(0.5,0.2,0.3,0.1,0.4,NA,0.7,0.2,0.6,0.1,0.4,0.9),ncol=3)
> cov2cor(cov(x,use="pairwise.complete.obs"))
[,1] [,2] [,3]
[1,] 1.0000000 0.4653400 -0.1159542
[2,] 0.4653400 1.0000000
2005 Feb 16
2
phi correlation
Hello my big problem is, i can´t find the phi-correlation instruction in the
R - programm. (correlation method= spearman, pearson, kendall, I have
found)
I also cant find the transform instruction which I can transform rational
vector into nominal vectors (binary)
Transforming into ordinaI I have found with the “rank” instruction, but I
have no found into nominal dates.
Please help