Displaying 20 results from an estimated 70 matches similar to: "about lm restrictions..."
2005 May 19
1
logistic regression: differential importance of regressors
Hi, All. I have a logistic regression model that I have run. The
question came up: which of these regressors is more important than
another?
(I'm using Design)
Logistic Regression Model
lrm(formula = iconicgesture ~ ST + SSP + magnitude + Condition +
Expertise, data = d)
Coef S.E. Wald Z P
Intercept -3.2688 0.2854 -11.45 0.0000
ST 2.0871 0.2730 7.64
2011 May 01
0
Dummy variables using rfe in caret for variable selection
I'm trying to run "rfe" for variable selection in the caret package, and am
getting an error. My data frame includes a dummy variable with 3 levels.
x <- chlDescr
y <- chl
#crate dummy variable
levels(x$State) <- c("AL","GA","FL")
dummy <- model.matrix(~State,x)
z <- cbind(dummy, x)
#remove State category variable
w <- z[,c(-4)]
2003 Sep 30
0
lme vs. aov
Hi,
I have a question about using "lme" and "aov" for the
following dataset. If I understand correctly, using
"aov" with Error term in the formula is equivalent to
using "lme" with default settings, i.e. both assume
compound symmetry correlation structure. And I have
found that equivalency in the past. However, with the
follwing dataset, I got different
2003 Oct 02
0
lme vs. aov with Error term
Hi,
I have a question about using "lme" and "aov" for the
following dataset. If I understand correctly, using
"aov" with an Error term in the formula is equivalent
to using "lme" with default settings, i.e. both assume
compound symmetry correlation structure. And I have
found that equivalency in the past. However, with the
follwing dataset, I got different
2003 Oct 01
0
lme vs. aov with Error term again
Hi all,
Sent the following question yesterday, but haven't got
any suggestions yet. So just trying again, can anyone
comment on the problem that I have? Thank you!
-------------
Hi,
I have a question about using "lme" and "aov" for the
following dataset. If I understand correctly, using
"aov" with an Error term in the formula is equivalent
to using
2005 May 26
0
Confidence intervals for prediction based on the logistic equation
Greetings,
We are performing a meta-analysis of mink pup survival data versus
chemical concentration. We have modeled percent survival successfully
using nls as shown below and the plot. What we need to do is construct a
confidence interval on the concentration at which we get 50% survival
(aka the EC50, although we may want other percent survivals in the
future). My first question is, what seems
2003 Oct 02
0
RE: [S] lme vs. aov with Error term
Hi Bert,
Thanks for the suggestions. I tried lme with different
control parameters, and also tried using "ML", instaed
of "REML", but still got the same answers.
Yes, I hope some gurus on this list could give me some
hints.
Thanks
--- "Gunter, Bert" <bert_gunter at merck.com> wrote:
> But they are close. This is almost certainly a
> numeric issue --
2018 Mar 15
0
DNS Updates fail with dns_tkey_gssnegotiate: TKEY is unacceptable
Hi,
I have a test system with two DCs based on samba v 4.8.0 with BIND9_DLZ as the
dns backend running on a fresh install of Gentoo. I can't get DNS Updates to
work on both DCs. If I issue the command: samba_dnsupdate --verbose after the
2nd DC has joined the domain I get the errors (just showing the last entry):
update(nsupdate): SRV
2003 Jan 20
1
quadratic trends and changes in slopes
I'd like to use linear and quadratic trend analysis in order to find
out a change in slope. Basically, I need to solve a similar problem as
discussed in http://www.gseis.ucla.edu/courses/ed230bc1/cnotes4/trend1.html
My subjects have counted dots: one dot, two dots, etc. up to 9 dots.
The reaction time increases with increasing dots. The theory is that
1 up to 3 or 4 points can be counted
2004 Dec 17
0
DHCP Handling and Traffic Control over a Working Load Balanced Dual ISP Setup
I have a working router (thanks to Julian''s patches and the threads on
this site) load balancing over Dual ISP''s.
Links for the curious (see router setup below as well) -
Necessary Patches - http://www.ssi.bg/~ja/
How to Patch (I use Debian Sarge and downloaded the latest source from
kernel.org) - http://www.desktop-linux.net/debkernel.htm
Necessary Reading -
2005 Sep 15
3
means comparison in R (post-hoc test)
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hi.
I have been using SAS for some time, and now I have discovered R. I am
very happy with it, but I have not found out how to perform some of the
multiple comparisons I was used to do in SAS.
With the SAS/STAT, I generally used the MEANS (for comparison of
arithmetic means) and the LSMEANS (for adjusted means) statements of the
GLM procedure (I
2011 Feb 10
2
Comparison of glm.nb and negbin from the package aod
I have fitted the faults.data to glm.nb and to the function negbin from the
package aod. The output of both is the following:
summary(glm.nb(n~ll, data=faults))
Call:
glm.nb(formula = n ~ ll, data = faults, init.theta = 8.667407437,
link = log)
Deviance Residuals:
Min 1Q Median 3Q Max
-2.0470 -0.7815 -0.1723 0.4275 2.0896
Coefficients:
2011 Sep 12
1
nested anova<-R chrashing
Hi,
I tried to do a nested Anova with the attached Data. My response
variable is "survivors" and I would like to know the effect of
(insect-egg clutch) "size", "position" (of clutch on twig) and "clone"
(/plant genotype) on the survival of eggs (due to predation). Each plant
was provided with three different sizes of clutches (45,15,5) and had
2006 Aug 24
1
how to constrast with factorial experiment
Hello, R users,
I have two factors (treat, section) anova design experiment where
there are 3 replicates. The objective of the experiment is to test if
there is significant difference of yield between top (section 9 to 11)
and bottom (section 9 to 11) of the fruit tree under treatment. I
found that there are interaction between two factors. I wonder if I
can contrast means from levels of
2005 Mar 01
3
Anova with Scheffe Tests
Hi R-people,
I am wanting to run Factorial ANOVA followed by Scheffe tests on some spatial subjective data. I'm comparing X-Y independent coordinates against x-y dependent coordinates. There are only four independent spatial coordinates that form a square.
I am wondering whether I am doing the right thing, because there doesn't seem to be a simple way of doing this. I have attempted to
2011 Jul 13
1
AR-GARCH with additional variable - estimation problem
Dear list members,
I am trying to estimate parameters of the AR(1)-GARCH(1,1) model. I have one
additional dummy variable for the AR(1) part.
First I wanted to do it using garchFit function (everything would be then
estimated in one step) however in the fGarch library I didn't find a way to
include an additional variable.
That would be the formula but, as said, I think it is impossible to add
2007 Nov 23
1
multiple comparisons/tukey kramer
Hi,
I'm trying to make sense of the options for multiple comparisons
options in R. I've found the following options:
pairwise.t.test, which provides standard t-tests, with options for
choosing an appropriate correction for multiple comparisons
TukeyHSD, which provides the usual Tukey test
glht(package multcomp), which provides a variety of options
>From the help list, it appears
2009 Feb 16
0
odd GARCH(1,1) results
Hi everybody,
I'm trying to fit a Garch(1,1) process to the DAX returns. My data
consists of about 2300 10day-logreturns in chronologically descending
order (see attachment). But if I use the garch function I get a very
high alpha_1 and a quite low beta, which doesn't make that much sense. I
think I am missing something, but have no idea what it might be. I'd
appreciate it a lot
2006 Aug 29
0
how to contrast with factorial experiment
Hello, R experts,
If I understand Ted's anwser correctly, then I can not contrast the
mean yields between sections 1-8 and 9-11 under "Trt" but I can
contrast mean yields for sections 1-3 and 6-11 because there exists
significant interaction between two factors (Trt:section4,
Trt:section5). Could I use the commands below to test
the difference between sections 1-3 and 6-11 ?
2007 Dec 21
1
post hoc in repeated measures of anova
Hallo, I have this dataset with repeated measures. There are two
within-subject factors, "formant" (2 levels: 1 and 2) and "f2 Ref" (25
levels: 670, 729, 788, 846, 905, 1080, 1100, 1120, 1140, 1170, 1480,
1470, 1450, 1440, 1430, 1890, 1840, 1790, 1740, 1690, 2290, 2210,
2120, 2040, 1950), and one between-subject factor, lang (2 levels:1
and 2). The response variable