Displaying 20 results from an estimated 10000 matches similar to: "function for the average or expected range?"
2008 Mar 21
1
function for the average or expected range?; CORECTION
Hi, All:
** My previous email on this subject seemed to contain an error; check
the correction:
Is there a function in R to compute the expected range of a sample
of size n from some distribution? I ask, because I was recently asked
about the control chart constant 'd2', which is the expected range for a
sample of size n from a standard normal.
There is a fairly simple
2008 Mar 21
0
function for the average or expected range?; CORECTION TO CORRECTION
Hi, All:
** My previous email on this subject seemed to contain an error; check
the correction below; please excuse my errors.
Is there a function in R to compute the expected range of a sample
of size n from some distribution? I ask, because I was recently asked
about the control chart constant 'd2', which is the expected range for a
sample of size n from a standard normal.
2002 Mar 22
0
sequential t-test - replies
[my original message to s-news & r-help is attached ]
No one possessed or knew of any S/R code for the sequential t-test. Also
it doesn't appear in the SAS index.
One or two suggested obtaining the S+ seqtrial software which may (or may
not) cover this, but this seemed to be a bit of a "hammer to crack a nut".
I have written a function based on the treatment in Wetheril
2008 May 29
1
plotting zoo using datetime as xlim
is there a way to use the actual index value for plotting zoo objects
this is the way that the index is set up and a sample range of what I would
like to plot
01/01/06 00:00:00 - 01/01/06 23:45:00
{
library(zoo)
# chron
library(chron)
fmt.chron <- function(x) {
chron(sub(" .*", "", x), gsub(".* (.*)", "\\1:00", x))
}}
x <- structure(c(15.57, 15.5,
2010 Aug 20
0
plotting moving range control chart with qcc. . .
This regards an old post that posed the question:
Tom Hodgess wrote:
"The problem is the (apparent?) inability to produce moving range
process behavior (a.k.a. "control") charts with individuals data in the
package "qcc" (v. 2.0). I have also struggled with the same limitation
in package "IQCC" (v. 1.0).
The package "qAnalyst" (v. 0.6.0) provides an
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,
2009 Oct 20
1
kendall.global
Hi every body:
I need some help with kendall.global. The example in the manual seems not working well, and cannot used with my data, always the same error.
data(mite)
> mite.hel <- decostand(mite, "hel")
>
> # Reproduce the results shown in Table 2 of Legendre (2005), a single group
> mite.small <- mite.hel[c(4,9,14,22,31,34,45,53,61,69),c(13:15,23)]
>
2011 Sep 02
1
Mann Kendall Test for Trend
Hi there,
I'm trying to apply the Mann Kendall test for trend analysis of a time
series. I have downloaded and installed the package Kendall and
subsequently loaded it into the software.
My time series is a .txt file with 2 columns - column 1 is the year (1985 -
2009) and column 2 is the corresponding entry variable.
According to the R guidelines, the call should be:
MannKendall(x)
2006 Jun 22
2
programming advice
Dear R users
I want to compute Kendall's Tau between two vectors x and y.
But x and y may have zeros in the same position(s) and I wrote the
following function to be sure to drop out those "double zeros"
"cor.kendall" <- function(x,y) {
nox <- c()
noy <- c()
#
for (i in 1:length(x)) if (x[i]!= 0 | y[i] != 0)
nox[length(nox)+1]<- x[i]
for (i in
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",
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
2004 May 13
1
Bootstrapping kendall cor
Dear R-helpers,
I'm fighting with the following problem :
I want to do bootstrapping on a Kendall correlation with the following code
:
> cor.function <- function(data,i) cor(data[i, 1], data[i,
2],method="kendall")
> boot.ci <- boot.ci(boot.cor <- boot(cbind(x,y),cor.function,
R=1000),conf=c(0.95,0.99))
However, I've got problems because I've got ties
2010 Jan 13
1
plotting moving range control chart
I have been having the same problem as poster Hodgess, below. It appears
that her question was never answered, so I would like to share a solution
with the community.
The problem is the (apparent?) inability to produce moving range process
behavior (a.k.a. "control") charts with individuals data in the package
"qcc" (v. 2.0). I have also struggled with the same limitation in
2011 Mar 28
0
Acessing Test Outputs for Writing to a Table
Hi all,
I am trying to write a script that will compute Kendall's tau for a 75 time
series (using the Kendall package) and will then write the tau and p values
from the Kendall test to a text file table that can be read into Excel.
I am having no problem calculating Kendall's tau and the associated p value
for each time series, but I am having trouble figuring out how aggregate the
2012 Aug 20
1
Kendall package tau-a, b, and c
Hi all,
I would like to ask a question related to Kendall package. I ran Kendall
(x,y) and
saw the results. But I am not sure which tau values R reported. I have
ties in
my data set, so I want tau-b. Can anybody tell how Kendall package is
calculating tau values? I have looked at the package PDF, but I could
not find
any useful information. As long as I see from the following
link, there
2007 Sep 06
3
kendall test
Hello,
I thougth that there is a function which does the kendall test in R,
I writed on the console apropos("kendall") and I didn't found anything can you tell me how could I do to use the kendall test?
Thanks.
_____________________________________________________________________________
l
[[alternative HTML version deleted]]
2011 Mar 21
1
Kendall v MannKendall Functions
Hi,
I am running a correlation analysis on a temporal dataset. I was wondering
if you would receive the same tau and p values running the function:
MannKendall(x), where x is the dependant variable that changes with time
as you would running:
Kendall(d,x), where x is the exact same dataset as the x entered into
MannKendall and d is the date on which the observation was made (assuming
that
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
2009 May 13
0
Mann-Kendall test
Dear useRs,
I've been trying to run a Mann-Kendall test in my data in order to detect trends.
I studied the examples given at the Kendall package and I can understand pretty well how it works on time-series data.
However, my data consists of values in different sites per year, as I display below;
Year 1 | Year 2 | Year 3 | ...
Site 1 x x x ...
2006 Sep 13
2
kendall's w
Hi,
I try to calculate Kendall's W coefficient and I have a bizarre error.
little.app.mat<-matrix(c(1,3,4,2,6,5,2,4,3,1,5,6,3,2,5,1,5,4),nrow=3,byrow=TRUE)
print(kendall.w(little.app.mat[-1,]))
>>> Kendall's W for ordinal data
>>> W = 0.7753623Error in if (is.na(x$p.table)) { : argument is of
length zero