Displaying 20 results from an estimated 400 matches similar to: "skewness and kurtosis in e1071 correct? (correction)"
2005 May 23
3
skewness and kurtosis in e1071 correct?
I wonder whether the functions for skewness and kurtosis in the e1071
package are based on correct formulas.
The functions in the package e1071 are:
# --------------------------------------------
skewness <- function (x, na.rm = FALSE)
{
if (na.rm)
x <- x[!is.na(x)]
sum((x - mean(x))^3)/(length(x) * sd(x)^3)
}
# --------------------------------------------
and
#
2005 Sep 20
1
Problem with read.spss() and as.data.frame(), or: alternative to subset()?
Trying to select a subset of cases (rows of data) I encountered several
problems:
Firstly, because I did not read the help to read.spss() thoroughly
enough, I treated the data read as a data frame. For example,
dr2000 <- read.spss('myfile.sav')
d <- subset(dr2000,RBINZ99 > 0)
and thus received an error message (Object "RBINZ99" not found), because
dr2000 is not a
2006 Jul 24
1
conflict of package "Matrix" and summary of lme object
After loading the package "Matrix" (version 0.995-12), using the summary
function with an lme (package nlme version 3.1-75) object results in an
error message saying
Fehler in dim(x) : kein Slot des Namens "Dim" f?r dieses Objekt der
Klasse "correlation"
(translated: 'Error in dim(x) : no slot of the name "Dim" for this
object of class
2005 Mar 14
2
par(new=TRUE) vs par(new=FALSE)
Just out of curiosity (and I hope that my question does not confuse
those who intuitively understood the par(new=TRUE) statement right in
the beginning):
I would like to know whether beginners (learning R) had the same
difficulty as I had: Intuitively I thought that par(new=TRUE) would draw
a new plot (and not into an already existing plot) and that
par(new=FALSE) would not draw a new plot
2006 Jul 24
3
standardized random effects with ranef.lme()
Using ranef() (package nlme, version 3.1-75) with an 'lme' object I can
obtain random effects for intercept and slope of a certain level (say:
1) - this corresponds to (say level 1) "residuals" in MLWin. Maybe I'm
mistaken here, but the results are identical.
However, if I try to get the standardized random effects adding the
paramter "standard=T" to the
2006 Aug 13
3
How to reply to a thread if receiving R-help mails in digest form
I receive R-help messages in digest form that makes it difficult to
answer a post. I noticed that my answer is not added to the thread
(instead, a new thread is started) although I use the same subject line
(starting with "Re: ") as the original post. Is there a solution (I
prefer the digest to separate messages for several reasons and don't
want to change my email reader)?
The
2005 Jul 19
2
using argument names (of indeterminate number) within a function
Although I tried to find an answer in the manuals and archives, I cannot
solve this (please excuse that my English and/or R programming skills
are not good enough to state my problem more clearly):
I want to write a function with an indeterminate (not pre-defined)
number of arguments and think that I should use the "..." construct and
the match.call() function. The goal is to write
2008 Mar 03
0
Fwd: R: Studdy Missing Data, differentiate between a percent with in the valid answers and with in the different missing answers
Begin forwarded message:
> Subject: R: Studdy Missing Data, differentiate between a percent
> with in the valid answers and with in the different missing answers
> take a look at the Website from Dirk Enzmann:
> http://www2.jura.uni-hamburg.de/instkrim/kriminologie/Mitarbeiter/
> Enzmann/Software/Enzmann_Software.html
> He provides a function called "freq.r" - maybe
2004 Dec 13
3
Percentages in contingency tables *warning trivial question*
I hesitate to post this question in the light of recent threads, indeed
I have hesitated for several weeks, however I have come to a full stop
and really need some help if I am going to progress. I am a new user of
R for medical statistics. I have attempted to read all the relevant
documents, but would welcome any suggestions as to what I have missed.
I am trying to contruct "table 1"
2003 Jun 03
3
Update VR_7.1-6
The update of VR by downloading VR_7.1-6.zip and using install.packages
(from local zip files) fails with the following error message:
Error in file(file, "r") : unable to open connection
In addition: Warning message:
cannot open file `VR/DESCRIPTION'
Other packages can be installed without problems, except of dse_2003.4-1
with a similar error message.
Why?
Operating System:
2003 May 08
3
Avoiding loops to spare time and memory
Is it possible to avoid the loop in the following function (or make the
function otherwise more efficient) and can someone point me to a
possible solution? (It would be great if hours could be reduced to
seconds :-).
# ---------------------------------------------
RanEigen=function(items=x,cases=y,sample=z)
{
X=matrix(rnorm(cases*items),nrow=cases,byrow=F)
S=crossprod(X-rep(1,cases) %*%
2003 Sep 21
1
Zero inflated count models
Can someone show me how to specify zero inflated poisson and zero
inflated negative poisson models in R? I would like to replicate the
example given in Long (1997: Regression Models for Categorical and
Limited Dependent Variables) in Chapter 8.5 (pp. 242-247).
TIA
Dirk
*************************************************
Dr. Dirk Enzmann
Criminological Research Institute of Lower Saxony
2003 Sep 23
2
(Fwd) Re: goodfit macro
Dear R-Help:
As you can see, Prof. Friendly refers me to your site for an
executable version of vcd. I don't mean to be obtuse, but 15 minutes
spent exploring your site failed to locate a downloadable version of the
vcd package to which he referred.
I know plainly what this application can do. What I need to know is
how to obtain the application itself.
My thanks in advance for any
2008 Sep 23
3
Generating series of distributions with the same skewness and different kurtosis or with same kurtosis and different skewness?
Dear R users,
I hope to explain the concepts of skewness and kurtosis by generating
series of distributions with same skewness and different kurtosis or with
same kurtosis and different skewness, but it seems that i cannot find the
right functions.
I have searched the mailing list, but no answers were found.
Is it possible to do that in R? Which function could be used?
Thanks a lot.
--
2001 Sep 28
1
Generate rand. data with zero skewness and some kurtosis
Dear all,
Right now, I'm doing research about outlier in statistical data
(univariate and multivariate) and I want to simulate its behavior. My
problem is :
How to generate random data from distribution with zero skewness and
some kurtosis values in R ?
A. Kudus
=====================
Dept. of Statistics
Bandung Islamic University
I n d o n e s i a
==========================
2001 Oct 03
0
Summary : Generate random data from dist. with 0 skewness and some kurtosis
Thanks to all who response my problem. Here are my summary :
1. from Dirk Eddelbuettel <edd at debian.org>
We could try a mixture of normals -- ie flip a coin (use a uniform with
some cutoff c where 0 < c < 1 ) to choose between N(0, sigma_1) and N(0,
sigma_2).
2. from Michaell Taylor <michaell.taylor at reis.com>
We could use the gld library to specify the lambdas of
2003 Nov 08
1
notation for skewness and kurtosis
Hello everybody,
this is a bit off topic, so maybe you can just reply to me personally...
What is the typical notation for 'skewness', 'kurtosis' and maybe 'excess
kurtosis'?
Thank you,
Martina
--------------------------------------------------------------------------
Department of Statistics Office Phone: (614) 292-1567
1958 Neil Avenue, 304E Cockins Hall
2011 Jul 23
0
Testing two independent samples for null of same skewness and kurtosis?
Hello
I wonder whether there is an r tool or package available for testing for the
null of same skewness or kurtosis of two independent samples.
It semes that nsRFA package uses L-moments for soothing similar but I could
not get how to use the package for the above test.
Any pointers, help, example and etc. will be most welcome.
Many thanks
Ed
[[alternative HTML
2011 Oct 25
1
alternative option in skewness and kurtosis tests?
I have a question about the D'Agostino skewness test and the Anscombe-Glynn
kurtosis test.
agostino.test(x, alternative = c("two.sided", "less", "greater"))
anscombe.test(x, alternative = c("two.sided", "less", "greater"))
The option "alternative" in those two functions seems to be the null
hypothesis. In the output, the
1999 Jul 28
1
skewness, kurtosis
Dear R-Users and Developpers,
Currently R does not include functions to compute the skewness and
kurtosis. I programmed it myself in the following way, but probably
*real* programmers/statisticians can do that better:
mykurtosis <- function(x) {
m4 <- mean((x-mean(x))^4)
kurt <- m4/(sd(x)^4)-3
kurt
}
myskewness <- function(x) {
m3 <- mean((x-mean(x))^3)
skew <-