Displaying 20 results from an estimated 10000 matches similar to: "simultaneous confidence intervals for glm quasipoisson"
2010 Sep 11
3
confidence bands for a quasipoisson glm
Dear all,
I have a quasipoisson glm for which I need confidence bands in a graphic:
gm6 <- glm(num_leaves ~ b_dist_min_new, family = quasipoisson, data = beva)
summary(gm6)
library('VIM')
b_dist_min_new <- as.numeric(prepare(beva$dist_min, scaling="classical", transformation="logarithm")).
My first steps for the solution are following:
range(b_dist_min_new)
2012 Feb 04
3
effect function (effects package)
Dear all,
How does the effect() function in the effects package calculate effects and standard errors for glm quasipoisson models? I was using effect() to calculate the impact of increasing x to e + epsilon, and then finding the expected percent change. I thought that this effect (as a percentage) should be exp(beta*epsilon), where beta is the appropriate coefficient from the model, but
2012 Dec 18
0
R function for computing Simultaneous confidence intervals for multinomial proportions
Dear all,
Does someone know an R function implementing the method of Sison and
Glaz (1995) (see full ref below) for computing Simultaneous confidence
intervals for multinomial proportions?
As alternative method, I think to boostrap the mean of each proportion
and get in that way confidence interval of the mean.
I observed 21 times a response that could be one out of 8 categories
2013 Jan 31
2
glm poisson and quasipoisson
Hello,
I have a question about modelling via glm. I have a dataset (see dput)
that looks like as if it where poisson distributed (actually I would
appreciate that) but it isnt because mean unequals var.
> mean (x)
[1] 901.7827
> var (x)
[1] 132439.3
Anyway, I tried to model it via poisson and quasipoisson. Actually, just to
get an impression how glm works. But I dont know how to
2008 Apr 17
2
glm(quasipoisson) with non-integer response
Hi,
I have count data that have been meddled with enough to make them non
integers. Using glm(poisson) returns a "non integer" error but
glm(quasipoisson) does not. Just wondering if anyone knows if I am
violating the assumptions of a quasipoisson error structure by using
these non-integer response data?
Thanks! I'd welcome your thoughts and/or references...
Mark
2005 Mar 11
2
Bonferroni simultaneous confidence intervals for multiple regression
Hi,
I'm having no luck figuring out how to find Bonferroni simultaneous confidence intervals to obtain a family of estimates in R. Does anyone know how to do this?
Thank you!
2010 Oct 19
2
Strange glm(, quasipoisson) error
Dear list,
I have recently encountered an odd error when running glm(dep~indep,
quasipoisson): while, with a subset of my data, I could get a
perfectly reasonable model, once I include all of my data (17K+
observations, 29 variables), I get the following error:
Error in if (any(y < 0)) stop("negative values not allowed for the
quasiPoisson family") :
missing value where
2023 Apr 09
1
simultaneous confidence intervals for multinomial proportions: sample size
Hello!
I want to calculate simultaneous confidence intervals for a nominal variable with three categories: "yes", "no", "partially" and I expect that far more than 5 samples fall into each category.
I have read that Glaz & Sison's method is only appropriate for variables with 7 or more categories. Therefore, the Goodman method seems like a good idea.
I have
2003 Mar 12
2
quasipoisson, glm.nb and AIC values
Dear R users,
I am having problems trying to fit quasipoisson and negative binomials glm.
My data set
contains abundance (counts) of a species under different management regimens.
First, I tried to fit a poisson glm:
> summary(model.p<-glm(abund~mgmtcat,poisson))
Call:
glm(formula = abund ~ mgmtcat, family = poisson)
.
.
.
(Dispersion parameter
2008 Aug 11
1
Prediction confidence intervals for a Poisson GLM
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Nom : non disponible
URL : <https://stat.ethz.ch/pipermail/r-help/attachments/20080811/b8dc0378/attachment.pl>
2009 Oct 05
2
GLM quasipoisson error
Hello,
I'm having an error when trying to fit the next GLM:
>>model<-glm(response ~ CLONE_M + CLONE_F + HATCHING
+(CLONE_M*CLONE_F) + (CLONE_M*HATCHING) + (CLONE_F*HATCHING) +
(CLONE_M*CLONE_F*HATCHING), family=quasipoisson)
>> anova(model, test="Chi")
>Error in if (dispersion == 1) Inf else object$df.residual :
missing value where TRUE/FALSE needed
If I fit
2008 Nov 29
1
function for simultaneous confidence interval of regression coefficients
List,
Would someone be so kind as to point me to a function that will calculate
simultaneous confidence intervals of regression coefficients based upon
their distribution as (under the assumption of normal errors, with
\mathbf{X} as the design matrix):
$\hat{\mathbf{\beta}} \sim N(\mathbf{\beta},
\sigma^2(\mathbf{X}^T\mathbf{X})^{-1})$.
'confint' calculates individual coefficients so
2007 Aug 03
1
extracting dispersion parameter from quasipoisson lmer model
Hi,
I would like to obtain the dispersion parameter for a quasipoisson model for later use in calculating QAIC values for model comparison.Can anyone suggest a method of how to go about doing this?
The idea I have now is that I could use the residual deviance divided by the residual degrees of freedom to obtain the dispersion parameter. The residual deviance is available in the summary
2011 Dec 08
1
prop.test() and the simultaneous confidence interval for multiple proportions in R
Dear list members,
I want to perform in R the analysis "simultaneous confidence interval for multiple proportions", as illustrated in the article of Agresti et al. (2008) "Simultaneous confidence intervals for comparing binomial parameter", Biometrics 64, 1270-1275.
If I am not wrong the R function implementing the Agresti et al. method is prop.test(). I ask an help because I
2012 Oct 01
0
[Fwd: REML - quasipoisson]
Hi Greg,
For quasi families I've used extended quasi-likelihood (see Mccullagh
and Nelder, Generalized Linear Models 2nd ed, section 9.6) in place of
the likelihood/quasi-likelihood in the expression for the (RE)ML score.
I hadn't realised that this was possible before the paper was published.
best,
Simon
ps. sorry for slow reply, the original message slipped through my filter
for
2008 Dec 01
1
Comparing output from linear regression to output from quasipoisson to determine the model that fits best.
R 2.7
Windows XP
I have two model that have been run using exactly the same data, both fit using glm(). One model is a linear regression (gaussian(link = "identity")) the other a quasipoisson(link = "log"). I have log likelihoods from each model. Is there any way I can determine which model is a better fit to the data? anova() does not appear to work as the models have the
2011 Feb 04
0
GAM quasipoisson in MuMIn - SOLVED
Hi,
Got my issues sorted.
Error message solved:
I heard from the guy who developed MuMIn and his suggestion worked.
"As for the error you get, it seems you are running an old version of MuMIn.
Please update the package first."
I did (I was only 1 version behind in both R and in MuMIn) and error
disappeared!
Running quasipoisson GAM in MuMIn:
As for my questions on GAM and " to
2009 Apr 11
0
Sean / Re: question related to fitting overdispersion count data using lmer quasipoisson
Hey Buddy,
Hope you have been doing well since last contact.
If you have the answer to the following question, please let me know.
If you have chance to travel up north. let me know.
best,
-Sean
---------- Forwarded message ----------
From: Sean Zhang <seanecon@gmail.com>
Date: Sat, Apr 11, 2009 at 12:12 PM
Subject: question related to fitting overdispersion count data using lmer
2012 Sep 25
1
REML - quasipoisson
hi
I'm puzzled as to the relation between the REML score computed by gam and
the formula (4) on p.4 here:
http://opus.bath.ac.uk/22707/1/Wood_JRSSB_2011_73_1_3.pdf
I'm ok with this for poisson, or for quasipoisson when phi=1.
However, when phi differs from 1, I'm stuck.
#simulate some data
library(mgcv)
set.seed(1)
x1<-runif(500)
x2<-rnorm(500)
2010 Jan 22
1
confidence intervals for mean (GLM)
Dear useRs,
How could I obtain the confidence intervals for the means of my treatments, when my data was fitted to a GLM?
I need the CI's for the Poisson and Negative Binomial distributions.
Here's what I have:
mydata1 <- data.frame('treatments'=gl(4,20), 'value'=rpois(80, 1))
model1 <- glm(value ~ treatments, data=mydata1, family=poisson)
means1 <-