Displaying 20 results from an estimated 10000 matches similar to: "Apparant bug in binomial model in GLM (PR#13434)"
2010 Apr 16
2
Weights in binomial glm
I have some questions about the use of weights in binomial glm as I am
not getting the results I would expect. In my case the weights I have
can be seen as 'replicate weights'; one respondent i in my dataset
corresponds to w[i] persons in the population. From the documentation
of the glm method, I understand that the weights can indeed be used
for this: "For a binomial GLM prior
2011 Feb 20
8
Generating uniformly distributed correlated data.
I wish to generate a vector of uniformly distributed data with a
defined correlation to another vector
The only function I have been able to find doing something similar is
corgen from the library ecodist.
The following code generates data with the desired correlation to the
vector x but the resulting vector y is normal and not uniform
distributed
library(ecodist)
x <- runif(10^5)
y
2006 Feb 17
2
Something changed and glm(..., family=binomial) doesn't work now
I ran logistic regression models last week using glm
(...,family=binomial) and got a set of results. Since then I have
loaded the Epi package for ROC analysis. Now when I run those same
models I get completely different results, with most being:
Warning message:
fitted probabilities numerically 0 or 1 occurred in: glm.fit(x = X, y
= Y, weights = weights, start = start, etastart = etastart,
2006 Jun 09
1
glm with negative binomial family
I am analysing parasite egg count data and am having trouble with glm with a
negative binomial family.
In my first data set, 55% of the 3000 cases have a zero count, and the
non-zero counts range from 94 to 145,781.
Eventually, I want to run bic.glm, so I need to be able to use glm(family=
neg.bin(theta)). But first I ran glm.nb to get an estimate of theta:
> hook.nb<- glm.nb(fh,
2011 Feb 16
1
Saturated model in binomial glm
Hi all,
Could somebody be so kind to explain to me what is the saturated model
on which deviance and degrees of freedom are calculated when fitting a
binomial glm?
Everything makes sense if I fit the model using as response a vector of
proportions or a two-column matrix. But when the response is a factor
and counts are specified via the "weights" argument, I am kind of lost
as far as
2009 Dec 17
4
Fishers exact test at < 2.2e-16
In an effort to select the most appropriate number of clusters in a
mixture analysis I am comparing the expected and actual membership of
individuals in various clusters using the Fisher?s exact test. I aim
for the model with the lowest possible p-value, but I frequently get
p-values below 2.2e-16 and therefore does not get exact p-values with
standard Fisher?s exact tests in R.
Does anybody know
2007 Dec 29
1
COMPAR.GEE error with logistic model
Hello,
I am trying to run the APE program COMPAR.GEE with a model containing a
categorical response variable and a mixture of continuous and categorical
independent variables. The model runs when I have categorical (binary)
response and two continuous independent variables (VAR1 and VAR2), but when
I include a categorical (binary) independent variable (VAR3), I receive the
following output with
2005 Jun 16
1
logistic regression - using polys and products of features
Hi
I can get all my features by doing this:
> logistic.model = glm(similarity ~ ., family=binomial, data =
cData[3001:3800,])
I can get the product of all my features by this:
logistic.model = glm(similarity ~ . ^ 2, family=binomial, data =
cData[3001:3800,])
I don't seem to be able to get polys by doing this:
logistic.model = glm(similarity ~ poly(.,2), family=binomial, data
2006 Aug 31
3
what's wrong with my simulation programs on logistic regression
Dear friends,
I'm doing a simulation on logistic regression model, but the programs can't
work well,please help me to correct it and give some suggestions.
My programs:
data<-matrix(rnorm(400),ncol=8) #sample size is 50
data<-data.frame(data)
names(data)<-c(paste("x",1:8,sep="")) #8 independent variables,x1-x8;
#logistic regression model is
2006 Jan 15
1
problems with glm
Dear R users,
I am having some problems with glm. The first is an error message "subscript out of bounds". The second is the fact that reasonable starting values are not accepted by the function.
To be more specific, here is an example:
> success <- c(13,12,11,14,14,11,13,11,12)
> failure <- c(0,0,0,0,0,0,0,2,2)
> predictor <- c(0,80*5^(0:7))
>
2005 Jan 28
3
GLM fitting
DeaR R-useRs,
I'm trying to fit a logist model with these data:
> dati
y x
1 1 37
2 1 35
3 1 33
4 1 40
5 1 45
6 1 41
7 1 42
8 0 20
9 0 21
10 0 25
11 0 27
12 0 29
13 0 18
I use glm(), having this output:
> g<-glm(y~x,family=binomial,data=dati)
Warning messages:
1: Algorithm did not converge in: glm.fit(x = X, y =
Y, weights = weights, start = start, etastart =
2005 Aug 05
1
question regarding logit regression using glm
I got the following warning messages when I did a
binomial logit regression using glm():
Warning messages:
1: Algorithm did not converge in: glm.fit(x = X, y =
Y, weights = weights, start = start, etastart =
etastart,
2: fitted probabilities numerically 0 or 1 occurred
in: glm.fit(x = X, y = Y, weights = weights, start =
start, etastart = etastart,
Can some one share your thoughts on how to
2008 Aug 08
2
[lme4]Coef output with binomial lmer
Dear R users
I have built the following model
m1<-lmer(y~harn+foodn+(1|ass%in%pop%in%fam),family = "quasibinomial")
where y<-cbind(alive,dead)
where harn and foodn are categorical factors and the random effect is a
nested term to represent experimental structure
e.g. Day/Block/Replicate
ass= 5 level factor, pop= 2 populations per treatment factor in each
assay, 7 reps
2019 Nov 28
4
Coeficientes GLM binomial
Estimad en s errer en s
He hecho este modelo glm
m1.pile<-glm(ger~tem+pot+time+I(tem^2)+I(tem^2):pot
,family="binomial"
,data=long.PILE
)
Que nos da la probabilidad de germinaciĆ³n de una semilla en funciĆ³n de tem
(Temperatura), pot (Humedad del suelo) y time (Tiempo que la semilla pasa
en esas condiciones).
Ahora quiero, para diferentes tem, pot
2010 Jul 22
1
GLM Starting Values
Hello,
Suppose one is interested in fitting a GLM with a log link to binomial data. How does R choose starting values for the estimation procedure? Assuming I don't supply them.
Thanks,
Tyler
2009 Mar 27
1
deleting/removing previous warning message in loop
Hello R Users,
I am having difficulty deleting the last warning message in a loop so that the only warning that is produced is that from the most recent line of code. I have tried options(warn=1), rm(last.warning), and resetting the last.warning using something like:
> warning("Resetting warning message")
This problem has been addressed in a previous listserve string,
2007 Nov 13
2
question about glm behavior
Hello,
I was trying a glm fitting (as shown below) and I got a warning and a fitted
residual deviance larger than the null deviance. Is this the expected
behavor of glm? I would expect that even though the warning might be
warranted I should not get worse fitting with an additional covariate in the
model. Could anyone tell me what I'm missing?
I get the same results in both R2.5.1 on windows
2005 Apr 13
1
logistic regression weights problem
Hi All,
I have a problem with weighted logistic regression. I have a number of
SNPs and a case/control scenario, but not all genotypes are as
"guaranteed" as others, so I am using weights to downsample the
importance of individuals whose genotype has been heavily "inferred".
My data is quite big, but with a dummy example:
> status <- c(1,1,1,0,0)
> SNPs <-
2005 Sep 22
3
anova on binomial LMER objects
Dear R users,
I have been having problems getting believable estimates from anova on a
model fit from lmer. I get the impression that F is being greatly
underestimated, as can be seen by running the example I have given below.
First an explanation of what I'm trying to do. I am trying to fit a glmm
with binomial errors to some data. The experiment involves 10
shadehouses, divided between
2006 Nov 12
2
segfault 'memory not mapped', dual core problem?
I encountered a segfault running glm() and wonder if it could have
something to do with the way memory is handled in a dual core system
(which I just set up). I'm running R-base-2.4.0-1, installed from the
SuSE 10.1 x86_64 rpm (obtained from CRAN). (My processor is an AMD
Athlon 64 x2 4800+).
The error and traceback are
*** caught segfault ***
address 0x8001326f2b, cause 'memory not