Displaying 20 results from an estimated 1000 matches similar to: "Vector errors and missing values"
2011 Jul 18
1
Missing values and geeglm
Dear all
I am struggling with how to deal with missing values using geeglm. I know
that geeglm only works with complete datasets, but I cannot seem to get the
na.omit function to work. For example
assuming DataMiss contains 3 columns, each of which has missing
observations, and an id column with no missing info then identifies the
clusters.
Outcome: 2 level integer
Predictor: numeric variable
2005 Jun 16
1
mu^2(1-mu)^2 variance function for GLM
Dear list,
I'm trying to mimic the analysis of Wedderburn (1974) as cited by
McCullagh and Nelder (1989) on p.328-332. This is the leaf-blotch on
barley example, and the data is available in the `faraway' package.
Wedderburn suggested using the variance function mu^2(1-mu)^2. This
variance function isn't readily available in R's `quasi' family object,
but it seems to me
2007 Feb 10
2
error using user-defined link function with mixed models (LMER)
Greetings, everyone. I've been trying to analyze bird nest survival
data using generalized linear mixed models (because we documented
several consecutive nesting attempts by the same individuals; i.e.
repeated measures data) and have been unable to persuade the various
GLMM models to work with my user-defined link function. Actually,
glmmPQL seems to work, but as I want to evaluate a suite of
2005 Jun 14
1
New Family object for GLM models...
Dear R-Users,
I wish to create a new family object based on the Binomial family. The only difference will be with the link function. Thus instead if using the 'logit(u)' link function, i plan to use '-log(i-u)'.
So far, i have tried to write the function following that of the Binomial and Negative Binomial families.
The major problem i have here is with the definition of the
2008 Apr 03
1
help with R semantics
Greetings:
I'm running R2.6.2 on a WinXP DELL box with 2 gig RAM.
I have created a new glm link function to be used with family = binomial.
The function works (although any suggested improvements would be welcome),
logit.FC <- function(POD.floor = 0, POD.ceiling =1)
{ if (POD.floor < 0 | POD.floor > 1) stop ("POD.floor must be between zero
and one.")
if
2012 Aug 15
3
Basic question -loading data
Hi all,
New user here - I include the following command in the prompt
read.csv("document.csv", header = TRUE )
and the output shows up.
But when I include the following command
summary(data)
I get the following message "Error in object[[i]] : object of type 'closure' is not subsettable"
Can someone please advise why R is not reading my data?
Thanks
2002 Feb 27
1
Bug in glm.fit? (PR#1331)
G'day all,
I had a look at the GLM code of R (1.4.1) and I believe that there are
problems with the function "glm.fit" that may bite in rare
circumstances. Note, I have no data set with which I ran into
trouble. This report is solely based on having a look at the code.
Below I append a listing of the glm.fit function as produced by my
system. I have added line numbers so that I
2006 Jan 14
2
initialize expression in 'quasi' (PR#8486)
This is not so much a bug as an infelicity in the code that can easily
be fixed.
The initialize expression in the quasi family function is, (uniformly
for all links and all variance functions):
initialize <- expression({
n <- rep.int(1, nobs)
mustart <- y + 0.1 * (y == 0)
})
This is inappropriate (and often fails) for variance function
"mu(1-mu)".
2002 Apr 15
1
glm link = logit, passing arguments
Hello R-users.
I haven't use R for a life time and this might be trivial - I hope you do
not mind.
I have a questions about arguments in the Glm-function. There seems to be
something that I cannot cope.
The basics are ok:
> y <- as.double(rnorm(20) > .5)
> logit.model <- glm(y ~ rnorm(20), family=binomial(link=logit), trace =
TRUE)
Deviance = 28.34255 Iterations - 1
2006 Apr 16
3
second try; writing user-defined GLM link function
I apologize for my earlier posting that, unbeknownst to me before,
apparently was not in the correct format for this list. Hopefully this
attempt will go through, and no-one will hold the newbie mistake
against me.
I could really use some help in writing a new glm link function in
order to run an analysis of daily nest survival rates. I've struggled
with this for weeks now, and can at least
2005 Apr 14
0
predict.glm(..., type="response") dropping names (and a propsed (PR#7792)
Here's a patch that should make predict.glm(..., type="response") retain the
names. The change passes make check on our Opteron running SLES9. One
simple test is:
names(predict(glm(y ~ x, family=binomial,
data=data.frame(y=c(1, 0, 1, 0), x=c(1, 1, 0, 0))),
newdata=data.frame(x=c(0, 0.5, 1)), type="response"))
which gives
[1]
2008 May 20
1
"NOTE" warning
Dear all
I am using NAMESPACE in my package but I would like the user to be able
to overwrite four functions:
own.linkfun, own.linkinv, own.mu.eta and own.valideta.
These are used to defined "own" link functions.
Is there any way of doing that without getting the when I am checking
the package?
This is what I am getting:
make.link.gamlss : linkfun: no visible binding for global
2006 Jul 30
1
Parametric links for glm?
At useR 2006 I mentioned that it would be nice to have a way to
specify binomial links
that involved free parameters and described some experience with a
Gosset link involving
a free degrees of freedom parameter, and a Tukey-lambda link with two
free parameters.
My implementation of this involved some rather kludgey modifications
of binomial,
make.link and glm that (essentially) added a
2002 Mar 29
1
glm start/offset bugs (PR#1422)
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There's a simple bug in the handling of the start and offset arguments
in glm and glm.fit. The bug exists in the latest development version
of R (version information below), but it appears that glm.R has not
been touched much lately, so the bug affects at
2011 Jan 28
2
help with S4 objects: trying to use a "link-glm" as a class in an object definition
Hi,
I'm trying to make a new S4 object with a slot for a "link-glm" object. R doesn't like me have a slot of class "link-glm"
> class(make.link("probit"))
[1] "link-glm"
> setClass("a",representation(item="link-glm"))
[1] "a"
Warning message:
undefined slot classes in definition of "a": item(class
2008 Jun 13
1
Writing a new link for a GLM.
Hi,
I wish to write a new link function for a GLM. R's glm routine does
not supply the "loglog" link. I modified the make.link function adding
the code:
}, loglog = {
linkfun <- function(mu) -log(-log(mu))
linkinv <- function(eta) exp(-exp(-eta))
mu.eta <- function(eta) exp(-exp(-eta)-eta)
valideta <- function(eta) all(eta != 0)
2003 Oct 27
1
Bioassays Yielding concentration-Mortality data
Dear all,
I'm trying reproduce an example of bioassays Yielding Concentration-Mortality Data particularly control - adjustment model from book Bioassay of Entomopathogenic Microbes and Nematodes chapter 7 with R.
I used glm with family=binomial and link=probit, but I do not know how to implement parameter gamma (control mortality - mortality of the untreated control insect in this exaple)
2001 Dec 18
2
Aranda-Ornaz links for binary data
Hi,
I would like apply different link functions from Aranda-Ordaz (1981)
family to large binary dataset (n = 2000). The existing links in glm for
binomial data (logit, probit, cloglog) are not adequate for my data, and I
need to test some other transformations.
Is it possible to do this in R? And how?
Thank you for your help,
/Sharon
2013 Feb 21
0
Odd Error message with rare events logit
I'm running a rare events logit model in R using the Zelig package and am
getting some of the oddest error messages that I can't figure out.
y = rnorm(100)
x = c(rep("0",1), rep("1",99))
d = data.frame(won=x, bid=y)
d
mod1 <- zelig(y~x, model="relogit", data=d, tau=1/100,
case.correct="prior", bias.correct=TRUE, robust=TRUE)
> mod1 <-
2007 Dec 15
1
modify a data.frame within a function
Hello all,
I'm trying to modify a single column of a data frame to remove randomly half of the values. I want to do it within a function, but can not assign the modified column back into the data frame. It was easy and successful without a function, so I suspect the problem is the call of the single column within the function.
removedata<-function(datafull,var.removed)
{
attach(datafull)