Displaying 20 results from an estimated 4000 matches similar to: "Finding out collinearity in regression"
2005 Jul 13
2
convert to chron objects
Hi,
I have a column of a dataframe which has time stamps
like:
> eh$t[1]
[1] 06/05/2005 01:15:25
and was wondering how to convert it to chron variable.
Thanks a lot.
Young.
2012 Apr 03
1
how to use condition indexes to test multi-collinearity
Dear Users,
I try to calculate condition indexes and variance decomposition proportions
in order to test for collinearity using colldiag() in perturb package, I
got
a large index and two variables with large variance decomposition
proportions,but one of them is constant item.I also checked the VIF for
that
variable, the value is small.The result is as follows:
Index intercept V1
2009 Jul 21
2
Collinearity in Linear Multiple Regression
Dear all,
How can I test for collinearity in the predictor data set
for multiple linear regression.
Thanks
Alex
[[alternative HTML version deleted]]
2013 Feb 06
1
how to extract test for collinearity and constantcy used in lda
Hi everyone,
I'm trying to vectorize an application of lda to each 2D slice of a 3D
array, but am running into trouble: It seems there are quite a few 2D
slices that trigger either the "variables are collinear" warning, or worse,
trigger a "variable appears to be constant within groups" error and fails
(i.e., ceases computation rather than skips bad slice).
There are
2008 Nov 20
1
Checking collinearity using lmer
I am running a logistic regression model with a random effect using lmer. I am uncertain how to check for collinearity between my parameters. I have already run cor() and linear regression for each combination of parameters, and all Rsqr values were <0.8….but I am analyzing ecological data so a 0.8 cutoff may be unrealistic.
-is there a way to check variance inflation factors or tolerance
2005 Mar 31
0
perturb package for evaluating collinearity
I've uploaded the R package "perturb" to CRAN. Perturb contains two
programs for evaluating collinearity. "Colldiag" calculates condition
indexes and variance decomposition proportions to detect and track
down collinear sets of variables.
"Perturb" takes a different approach. It re-estimates the model a
specified number of times, adding random noise
2005 Mar 31
0
perturb package for evaluating collinearity
I've uploaded the R package "perturb" to CRAN. Perturb contains two
programs for evaluating collinearity. "Colldiag" calculates condition
indexes and variance decomposition proportions to detect and track
down collinear sets of variables.
"Perturb" takes a different approach. It re-estimates the model a
specified number of times, adding random noise
2008 Sep 09
3
Splitting Data Frame into Two Based on Source Array
Dear all,
Suppose I have this data frame:
> data_main
V1 V2
foo 13.1
bar 12.0
qux 10.4
cho 20.33
pox 8.21
And I want to split the data into two parts
first part are the one contain in the source array:
> src
[1] "bar" "pox"
and the other one the complement.
In the end we hope to get this two dataframes:
> data_child1
V1 V2
bar 13.1
pox
2002 Jul 15
2
meaning of error message about collinearity
You are using a method that needs to estimate the covariance matrix of all
the variables. If you have 80 variables, there are (80+1)*80/2 = 3240
variances and covariances to estimate. How many data points do you think
you need to do that?
Some people assume the covariance matrix is diagonal (i.e., assuming all the
variables are uncorrelated). Even then you still have 80 variances to
estimate.
2005 Jun 24
1
"Error in contrasts" in step wise regression
Hi,
I have a problem in getting step function work. I am getting the following error:
> fit1 <- lm(Response~1)
> fmla <- as.formula(paste(" ~ ",paste(colnames,collapse="+")))
> sfit <- step(fit1,scope=list(upper= fmla,lower= ~1),k=log(nrow(dat)))
Start: AIC= -1646.66
Response ~ 1
Error in "contrasts<-"(`*tmp*`, value =
1999 Sep 22
2
SAMBA digest 2240
>
Hi,
Check if the shared directory has the write permission for all. i.e. chmod 777 for
the particular directory
> Date: Sun, 19 Sep 1999 21:06:36 -0700
> From: Kenny Cho <Kenny.Cho@Corp.Sun.COM>
> To: samba@samba.org
> Subject: Problem copying files to samba mount.
> Message-ID: <37E5B2CC.9ADC9F8A@ha1pal.corp.sun.com>
> MIME-Version: 1.0
>
2006 Feb 28
1
Collinearity in nls problem
Dear R-Help list,
I have a nonlinear least squares problem, which involves a changepoint;
at the beginning, the outcome y is constant, and after a delay, t0, y
follows a biexponential decay. I log-transform the data, to stabilize
the error variance. At time t < t0, my model is
log(y_i)=log(exp(a0)+exp(b0))
at time t >= t0, the model is
log(y_i)=log(exp(a0-a1*(t_i - t0))+exp(b0=b1*(t_i -
2010 Aug 03
2
Collinearity in Moderated Multiple Regression
Dear all,
I have one dependent variable y and two independent variables x1 and x2
which I would like to use to explain y. x1 and x2 are design factors in an
experiment and are not correlated with each other. For example assume that:
x1 <- rbind(1,1,1,2,2,2,3,3,3)
x2 <- rbind(1,2,3,1,2,3,1,2,3)
cor(x1,x2)
The problem is that I do not only want to analyze the effect of x1 and x2 on
y but
2005 Jul 22
1
find confounder in covariates
Hi,
I was wondering if there is a way, or function in R to
find confounders. For istance,
> a = sample( c(1:3), size=10,replace=T)
> X1 = factor( c('A','B','C')[a] )
> X2 = factor( c('Aa','Bb','Cc')[a] )
> Xmat = data.frame(X1,X2,rnorm(10),rnorm(10))
> dimnames(Xmat)[[2]] = c('z1','z2','z3','y')
Now,
2011 Feb 11
4
About classification methods.
Dear R users,
I'm new of the R, I really don't know much.
I want classification some data (two class, many features and huge size of data) by using R.
At this case, I want using Support Vector Machine, Bayes theory based classifier, Discriminant Analysis, Regression based at least.
Which package should I using, and can I compare each classifier result by predictions?
Thank you.
2017 Dec 25
2
[Bug 1206] New: segfault when snat map rule has been added
https://bugzilla.netfilter.org/show_bug.cgi?id=1206
Bug ID: 1206
Summary: segfault when snat map rule has been added
Product: nftables
Version: unspecified
Hardware: x86_64
OS: Ubuntu
Status: NEW
Severity: normal
Priority: P5
Component: nft
Assignee: pablo at netfilter.org
2008 Oct 06
10
DO NOT REPLY [Bug 5811] New: rsync error: error allocating core memory buffers (code 22) at io.c(635)
https://bugzilla.samba.org/show_bug.cgi?id=5811
Summary: rsync error: error allocating core memory buffers (code
22) at io.c(635)
Product: rsync
Version: 3.0.4
Platform: x64
OS/Version: Linux
Status: NEW
Severity: blocker
Priority: P3
Component: core
AssignedTo: wayned@samba.org
2006 Jun 23
4
English translation of article on HFSC
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Greetings all,
Working in concert with the original authors, Klaus Rechert and
Patrick McHardy, I have translated their article "HFSC Scheduling
mit Linux" [0] on Hierarchical Fair Service Curve (HFSC) into
English [1].
http://linux-ip.net/tc/hfsc.en/
Although the original content is not available directly from their
website,
2003 Sep 19
2
About PLS analysis
Dear colleagues,
May you point me out to the PLS module in R system?
I could not find it at all using "PLS" or "partial" as the search keywords.
Thank you.
Sokratis.
----------------------------------
Sokratis ALIKHANIDI, Ph.D.
Department of Knowledge-based Information Engineering
Toyohashi University of Technology
1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441, JAPAN
TEL:
2009 Jul 01
5
convert tabular time series into a matrix format
Hi, thanks everyone for any help in advance.
I found myself dealing with a tabular time-series data formatted each row
like [ time stamp, ID, values]. I made a small examples:
X = data.frame(t=c(1,1,1,2,2,2,2,3,3,3,4,4,4,5,5),id =