Displaying 20 results from an estimated 5000 matches similar to: "Zero-inflated Negative Binomial Error"
2010 Mar 03
1
Zero inflated negative binomial
Hi all,
I am running the following model:
> glm89.nb <- glm.nb(AvGUD ~ Year*Trt*Micro)
where Year has 3 levels, Trt has 2 levels and Micro has 3 levels.
However when I run it has a zero inflated negative binomial (as I have lots
of zeros) I get the below error message:
> Zinb <- zeroinfl(AvGUD ~ Year*Trt*Micro |1, data = AvGUD89, dist =
"negbin")
Error in optim(fn =
2011 May 23
1
Interpreting the results of the zero inflated negative binomial regression
Hi,
I am new to R and has been depending mostly on the online tutotials to learn
R. I have to deal with zero inflated negative binomial distribution. I am
however unable to understand the following example from this link
http://www.ats.ucla.edu/stat/r/dae/zinbreg.htm
The result gives two blocks.
*library(pscl)
zinb<-zeroinfl(count ~ child + camper | persons, dist = "negbin", EM =
2010 Feb 04
1
Zero inflated negat. binomial model
Dear R crew:
I think I am in the right mailing list. I have a very simple dataset consisting of two variables: cestode intensity and chick size (defined as CAPI). Intensity is clearly overdispersed, with way too many zeroes. I'm interested in looking at the association between these two variables, i.e. how well does chick size predict tape intensity?
I fit a zero inflated negat. binomial
2010 Feb 11
1
Zero-inflated Negat. Binom. model
Dear R crew:
I am sorry this question has been posted before, but I can't seem to solve
this problem yet.
I have a simple dataset consisting of two variables: cestode intensity and
chick size (defined as CAPI).
Intensity is a count and clearly overdispersed, with way too many zeroes.
I'm interested in looking at the association between these two variables,
i.e. how well does chick
2013 Jun 04
1
Zero-Inflated Negative Binomial Regression
Hi!
I'm running a zero-inflated negative binomial regression on a large (n=54822) set of confidential data. I'm using the code:
ZerNegBinRegress<-zeroinfl(Paper~.|., data=OvsP, dist="negbin", EM=TRUE)
And keep getting the error:
Warning message:
glm.fit: fitted probabilities numerically 0 or 1 occurred
I've done enough reading about this error to realize that I have
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.
2011 Jun 01
3
Zero-inflated regression models: predicting no 0s
Hi all,
First post for me here, but I have been reading on the forum for almost two
years now. Thanks to everyone who contributed btw!
I have a dataset of 4000 observations of count of a mammal and I am trying
to predict abundance from a inflated-zero model as there is quite a bit of
zeros in the response variable.
I have tried multiple options, but I might do something wrong as every
2005 Mar 03
1
Negative binomial regression for count data
Dear list,
I would like to fit a negative binomial regression model as described in "Byers AL, Allore H, Gill TM, Peduzzi PN., Application of negative binomial modeling for discrete outcomes: a case study in aging research. J Clin Epidemiol. 2003 Jun;56(6):559-64" to my data in which the response is count data. There are also 10 predictors that are count data, and I have also 3
2012 Jul 09
1
classification using zero-inflated negative binomial mixture model
Hi,
I want using zero-inflated negative binomial regression model to
classify data(a vector of data), that is I want know each observed value is
more likely belong to the "zero" or "count" distribution(better with
relative probability). My data is some like:
count site samp
12909 1 1
602 1 2
50 1 3
1218 1 4
91291 1 5
2011 Nov 17
1
How to Fit Inflated Negative Binomial
Dear All,
I am trying to fit some data both as a negative binomial and a zero
inflated binomial.
For the first case, I have no particular problems, see the small snippet
below
library(MASS) #a basic R library
set.seed(123) #to have reproducible results
x4 <- rnegbin(500, mu = 5, theta = 4)
#Now fit and check that we get the right parameters
fd <- fitdistr(x4, "Negative
2012 May 16
1
clusters in zero-inflated negative binomial models
Dear all,
I want to build a model in R based on animal collection data, that look like the following
Nr Village District Site Survey Species Count
1 AX A F Dry B 0
2 AY A V Wet A 5
3 BX B F Wet B 1
4 BY B V Dry B 0
Each data point shows one collection unit in a certain Village, District, Site, and Survey for a certain Species. 'Count' is the number of animals collected in that
2012 Jul 13
1
Vuong test
Dear All,
I am using the function vuong from pscl package to compare 2 non nested models NB1
(negative binomial I ) and Zero-inflated model.
NB1 <- glm(, , family = quasipoisson), it is an
object of class: "glm" "lm"
zinb <-
zeroinfl( dist = "negbin") is an object of class: "zeroinfl"
when applying vuong
function I get the following:
vuong(NB1,
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
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
2009 Mar 22
1
Multiple Comparisons for (multicomp - glht) for glm negative binomial (glm.nb)
Hi
I have some experimental data where I have counts of the number of
insects collected to different trap types rotated through 5 different
location (variable -location), 4 different chemical attractants [A, B,
C, D] were applied to the traps (variable - semio) and all were
trialled at two different CO2 release rates [1, 2] (variable CO2) I also
have a selection of continuous variables
2006 Jan 24
1
non-finite finite-difference value[]
Dear R-helpers,
running a zeroinflated model of the following type:
zinb = zeroinfl(count=response ~., x = ~ . - response, z = ~. - response,
dist = "negbin", data = t.data, trace = TRUE)
generates the following message:
Zero-Inflated Count Model
Using logit to model zero vs non-zero
Using Negative Binomial for counts
dependent variable y:
Y
0 1 2 3
359 52 7 3
generating
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
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
2010 Jun 08
2
Please help me
Dear Mr. or Ms.,
I used the R-software to run the zero-inflatoin negative binomial model (zeroinfl()) .
Firstly, I introduced one dummy variable to the model as an independent variable, and I got the estimators of parameters. But the results are not satisfied to me. So I introduced three dummy variables to the model. but I could not get the results. And the error message is
2005 Dec 02
1
Zero-inflated neg.bin. model and pscl package
Dear list,
I'm currently trying to develop a model to assess clam yield potential in a
lagoon. I'm using the zeroinfl function of the pscl package to fit a
Zero-inflated negative binomial model, given the high occurrence of zero
counts.
I don't understand from the sentence in the pscl guide "Zero-inflated count
models are a type of two-component mixture model, with a component