Displaying 20 results from an estimated 1000 matches similar to: "negative predicted values in poisson glm"
2008 Dec 16
1
Prediction intervals for zero inflated Poisson regression
Dear all,
I'm using zeroinfl() from the pscl-package for zero inflated Poisson
regression. I would like to calculate (aproximate) prediction intervals
for the fitted values. The package itself does not provide them. Can
this be calculated analyticaly? Or do I have to use bootstrap?
What I tried until now is to use bootstrap to estimate these intervals.
Any comments on the code are welcome.
2012 Jun 23
0
Using at.level() with a MCMCglmm zero-inflated poisson model
I have a question for users of MCMCglmm that have experience implementing
the zero-inflated poisson model.
I find that the documentation, and previous questions, do not offer a lot
of clear guidance on specifying and interpreting the zipoisson model. In
particular, I see a lot of zero-inflated poisson examples that use the
at.level(trait, x):variableName syntax.
Specifically, the MCMCglmm
2010 Apr 19
2
plotting RR, 95% CI as table and figure in same plot
Hi all--
I am in the process of helping colleagues write up a ms in which we fit
zero-inflated Poisson models. I would prefer plotting the rate ratios
and 95% CI (as I've found Gelman and others convincing about plotting
tables...), but our journals usually like the numbers themselves.
Thus, I'm looking at a recent JAMA article in which both numbers and
dotplot of RR and 95% CI are
2024 Jan 04
1
Obtaining a value of pie in a zero inflated model (fm-zinb2)
Are you referring to the zeroinfl() function in the countreg package? If
so, I think
predict(fm_zinb2, type = "zero", newdata = some.new.data)
will give you pi for each combination of covariate values that you
provide in some.new.data
where pi is the probability to observe a zero from the point mass component.
As to your second question, I'm not sure that's possible, for any
2011 Oct 11
1
Count model prediction
Hello ;
I am doing a regression of count data (number of award and there are some
covariates)
I have estiamted the parameters of negative binomial distribuion (lambda is
a function of covaraites, GLM model) by glm.nb function and training
dataset.
Now I want to predict the number of award (for example y=0, y=1, y=2,) or
testing dataset. I dont know how to calculate this numbers?
I would be very
2012 Apr 26
2
Lambert (1992) simulation
Hi,
I am trying to replicate Lambert (1992)'s simulation with zero-inflated
Poisson models. The citation is here:
@article{lambert1992zero,
Author = {Lambert, D.},
Journal = {Technometrics},
Pages = {1--14},
Publisher = {JSTOR},
Title = {Zero-inflated {P}oisson regression, with an application to defects
in manufacturing},
Year = {1992}}
Specifically I am trying to recreate Table 2. But my
2008 Oct 01
1
Negative Binomial Predictions
Good Day All,
I have a negative binomial model which I have developed using the MASS
library. I now would like to develop some predictions from it.
Running the predict.glm (stats library) using type="response" gives me a
non-integer value which was rather puzzling. I would like to confirm
that this is actually the mean predicted value of the probability mass
function as opposed
2012 May 05
0
Getting predicted values from a zero-inflated negative binomial using zeroinfl()
Hi,
I am a little confused at the output from predict() for a zeroinfl object.
Here's my confusion:
## From zeroinfl package
fm_zinb2 <- zeroinfl(art ~ . | ., data = bioChemists, dist = "negbin")
## The raw zero-inflated overdispersed data
> table(bioChemists$art)
0 1 2 3 4 5 6 7 8 9 10 11 12 16 19
275 246 178 84 67 27 17 12 1 2 1 1
2024 Jan 04
1
Obtaining a value of pie in a zero inflated model (fm-zinb2)
I am running a zero inflated regression using the zeroinfl function similar to the model below:
fm_zinb2 <- zeroinfl(art ~ . | ., data = bioChemists, dist = "poisson")
summary(fm_zinb2)
I have three questions:
1) How can I obtain a value for the parameter pie, which is the fraction of the population that is in the zero inflated model vs the fraction in the count model?
2) For
2001 Oct 04
1
sort data.frame and contour()
Dear all,
I would like to know if there is a function for sorting a data.frame based
on one column. sort() does it for a single vector but not for the whole
data. order() does it if there are relations between the columns but in my
case it is simply a data.frame.
Further, I would like to plot other data,
pop.size<- c(800, 800, 1500, 1000, 158, 300, 740, 250, 2000, 1500, 250, 700)
2008 Dec 11
2
how to get the CDF of a density() estimation?
Hi,
I've estimated a simple kernel density of a univariate variable with
density(), but after I would like to find out the CDF at specific
values.
How can I do it?
thanks for your help, with it I am very close to finish my first
little bit more serious work in R,
Viktor
2010 Apr 12
1
zerinfl() vs. Stata's zinb
Hello,
I am working with zero inflated models for a current project and I am
getting wildly different results from R's zeroinfl(y ~ x, dist="negbin")
command and Stata's zinb command. Does anyone know why this may be? I find
it odd considering that zeroinfl(y ~ x, dist="poisson") gives identical to
output to Stata's zip function.
Thanks,
--david
[[alternative
2007 Dec 20
2
Multicore computation in Windows network: How to set up Rmpi
R-users,
My question is related to earlier posts about benefits of quadcore over
dualcore computers; I am trying to setup a cluster of windows xp
computers so that eventually I could make use of 10-20 cpu:s, but for
learning how to do this, I am playing around with two laptops.
I thought that the package snow would come handy in this situation, but
to use snow, I would probably need to install
2003 Apr 24
5
Fast R implementation of Gini mean difference
I have written the following function to calculate the weighted mean
difference for univariate data (see
http://www.xycoon.com/gini_mean_difference.htm for a related
formula). Unsurprisingly, the function is slow (compared to sd or mad)
for long vectors. I wonder if there's a way to make the function
faster, short of creating an external C function. Thanks very much
for your advice.
gmd
2002 Nov 07
2
Cant run SSHD daemon
I have compiled openssh for sun solaris 2.6, no errors
When I try to run SSHD daemon it says the following error.
This platform does not support both privilege separation and compression
Compression disabled
Privilege separation user sshd does not exist
Any one that have answer to this problem mail me on daniel.d.olsson at telia.se <mailto:daniel.d.olsson at telia.se>
//Daniel
2005 Sep 01
5
Multivariate Skew Normal distribution
> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of Caio Lucidius
> Naberezny Azevedo
> Sent: 01 September 2005 12:09
> To: Help mailing list - R
> Subject: [R] Multivariate Skew Normal distribution
>
>
> Hi all,
>
> Could anyone tell me if there is any package (or function)
2003 Apr 28
4
Documentation
Dear Asterisk Users,
Are there any documentation that teach how to using Digium Cards to setup a
PABX system?
Thanks,
Randal
2003 May 20
4
Output to connections
In the document "R Data Import/Export", section "Output to connections",
there is the following portion of code:
## convert decimal point to comma in output, using a pipe (Unix)
zz <- pipe(paste("sed s/\\./,/ >", "outfile"), "w")
cat(format(round(rnorm(100), 4)), sep = "\n", file = zz)
close(zz)
## now look at the output
2008 Nov 06
1
trouble with html help
I have this problem with R 2.6.1 and 2.7.1 (have not tried others)
running on Windows XP:
Html help has wrong links to help files. The index.html is correctly
found from
file:///C:/PROGRA~1/R/R-26~1.1/doc/html/index.html
as well as the search engine
file:///C:/PROGRA~1/R/R-26~1.1/doc/html/search/SearchEngine.html
However, when I search for, say, "paste", I will be pointed to
2003 May 13
2
RMySQL crashes R
I have justed upgraded R v1.7.0 on Windows NT 4 and have installed the
latest RMySQL (version 0.5-1)and DBI (version 0.1-5) packages.
When I issue the following commands (tactfully adjusted) R just crashes and
disappears, any ideas?
require(RMySQL)
m <- dbDriver("MySQL")
con <- dbConnect(m, dbname="xxx", user="xxx", password="xxx",