Displaying 20 results from an estimated 1500 matches similar to: "Pierce's criterion"
2010 Sep 15
1
cochran-grubbs tests results
Hello,
I'm new in this R world and I don't know much about statistics, but now I
have to analize some data and I've got some first queries yet:
I have 5 sets of area mesures and each set has 5 repetitions.
My first step is to check data looking for outliers. I've used the outliers
package. I have to use the cochran test and the grubbs test in case I find
any outlier. The problem
2010 Nov 30
3
Outlier statistics question
I have a statistical question.
The data sets I am working with are right-skewed so I have been
plotting the log transformations of my data. I am using a Grubbs Test
to detect outliers in the data, but I get different outcomes depending
on whether I run the test on the original data or the log(data). Here
is one of the problematic sets:
fgf2p50=c(1.563,2.161,2.529,2.726,2.442,5.047)
2009 Feb 14
2
implementing Grubbs outlier test on a large dataframe
Hi!
I'm trying to implement an outlier test once/row in a large dataframe.
Ideally, I'd do this then add the Pvalue results and the number flagged as
an outlier as two new separate columns to the dataframe. Grubbs outlier
test requires a vector and I'm confused how to make each row of my dataframe
a vector, followed by doing a Grubbs test for each row containing the vector
of numbers
2005 Apr 14
2
grubbs.test
Dear All,
I have small samples of data (between 6 and 15) for
numerious time series points. I am assuming the data
for each time point is normally distributed. The
problem is that the data arrvies sporadically and I
would like to detect the number of outliers after I
have six data points for any time period. Essentially,
I would like to detect the number of outliers when I
have 6 data points then
2006 Jul 20
2
(robust) mixed-effects model with covariate
Dear all,
I am unsure about how to specify a model in R and I thought of asking
some advice to the list. I have two groups ("Group"= A, B) of
subjects, with each subject undertaking a test before and after a
certain treatment ("Time"= pre, post). Additionally, I want to enter
the age of the subject as a covariate (the performance on the test is
affected by age),
2011 Dec 30
3
good method of removing outliers?
Happy holidays all!
I know it's very subjective to determine whether some data is outlier or
not...
But are there reasonally good and realistic methods of identifying outliers
in R?
Thanks a lot!
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2007 Apr 25
1
How to identify and exclude the outliers with R?
Hello, everyone,
I want to ask a simple question.
If I have a set of data,and I want to identify how many outliers there are
in the data.Which packages and functions can I use?
Thanks.
Shao chunxuan.
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2007 Jun 19
5
outlying
hello,
are there functions to detecte outlying observations in samples?
thanks.
___________________________________________________________________________
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2004 Sep 23
6
detection of outliers
Hi,
this is both a statistical and a R question...
what would the best way / test to detect an outlier value among a series of 10 to 30 values ? for instance if we have the following dataset: 10,11,12,15,20,22,25,30,500 I d like to have a way to identify the last data as an outlier (only one direction). One way would be to calculate abs(mean - median) and if elevated (to what extent ?) delete the
2004 Jun 30
1
outlier tests
I have been learning about some outlier tests -- Dixon
and Grubb, specifically -- for small data sets. When
I try help.start() and search for outlier tests, the
only response I manage to find is the Bonferroni test
avaiable from the CAR package... are there any other
packages the offer outlier tests? Are the Dixon and
Grubb tests "good" for small samples or are others
more
2006 Nov 24
1
Splitting criterion in tree and rpart
? stato filtrato un testo allegato il cui set di caratteri non era
indicato...
Nome: non disponibile
Url: https://stat.ethz.ch/pipermail/r-help/attachments/20061124/6ac3d11f/attachment.pl
2005 Mar 11
2
smbldap-useradd -w problem
I'm in the process of learning Samba and evaluating it as a possible
replacement for Windows NT servers in our office next year. I have set up a
small test network comprised of one NT 4 (SP6a) Workstation, one Windows
2000 Pro (SP3) and one Fedora Core 3 running samba 3.0.11 as a PDC. I'm
using LDAP as the passdb backend with smbldap-tools 0.8.7-1. The Windows
2000 Pro machine can join the
2000 Jul 11
1
q() problem and more.
Hi Rers,
W/o trying to make a long story short (I hope you read that correctly), I
have been working on a nice little R function ...
Somewhere along the line I got an error that refers to a max function in
my function (I think this is a vector vs. scalar issue):
Error in max(..., na.rm = na.rm) : invalid "mode" of argument
If that's not bad enough, even when I q() R and say
2011 Dec 05
0
ANNOUNCEMENT: Call for Proposals for The R Series from Chapman & Hall/CRC
Chapman & Hall/CRC: The R Series
We are delighted to announce that our new series of books on R is up and running, with two books already published and another nine forthcoming (including three set to publish in 2012). We are keen to receive proposals for books covering all aspects of the development and application of R software. If you have an idea for a book, please contact one of the
2004 Feb 19
6
R for economists (was: Almost Ideal Demand System)
Hi,
I did not find any web page about using R in economics and econometrics so
far. However, this does not mean that there is none (searching with google
for "R" and "economics" gives many pages about economics and a name like
Firstname R. Lastname on it ;-)).
Does anybody in the list does know such a web page?
If not, I will be happy if you, Ajay, could build and
2004 Apr 25
7
R vs Matlab: which is more "programmer friendly"?
Hi,
The department of economics at our university (Budapest) is planning a
course on numerical methods in economics. They are trying to decide
which software to use for that, and I would like to advocate R. The
other alternative is Matlab.
I have found comparisons in terms of computational time for matrix
algebra, but I don't think that is relevant: the bottleneck for
economists is usually
2009 Dec 30
1
lm() and factors appending
How for the love of god can I prevent the lm() function from padding on to
my factor variables?
I start out with 2 tables:
Table1
123123
124351
...
626773
Table2
Count,IS_DEAD,IS_BURNING
1231,T,F
4521,F,T
...
3321,T,T
Everything looks fine when I import the data.
then we get a
oh_crap <- lm(table1 ~ Count + IS_DEAD + IS_BURNING, table2)
Magically when I look at my oh_crap coefficents
2000 Dec 10
0
Patents on algorithms harm data analytic services
Cologne, 10.12.00
Dear Sir,
Dear Madam,
We are concerned about the possibility that the European Commission might introduce software patenting into the European Community because we think this will harm our profession.
We make our living on data management and statistical analyses. Modern statistics crucially depends on algorithms [cf. Venables, W. N., & Ripley, B. D. (1999). Modern applied
2024 Mar 14
0
CADFtest difference between max.lag.y with criterion and without criterion
Dear Professor Bernhard,
Sorry for take your time, but I found something strange that I am not able to explain/understand.
Suppose that I compute the ADF test by using the criterion="BIC" to select the lags:
summary(CADFtest(y, max.lag.y = 20, type = "drift", criterion="BIC"))
Suppose that 2 lags are selected.
Next, if I set the lags to 2: summary(CADFtest(y,
2013 May 17
0
Using grubbs test for residuals to find outliers
Hi,
I am a new user of R.
This is a conceptual doubt regarding screeing out outliers from the dataset
in regression.
I read up that Cook's distance can be used and if we want to remove
influential observations, we can use the metric (>4/n) (n=no of
observations) to remove any outliers.
I also came across Grubb's test to identify outliers in univariate distns.
(assumed normal) but i