search for: zinb

...promise I have searched the forum already, but I'm getting a bit desperate! I have over-dispersed, zero inflated data, with variance greater than the mean, suggesting Zero-Inflated Negative Binomial - which I attempted in R with the pscl package suggested on http://www.ats.ucla.edu/stat/R/dae/zinbreg.htm However my data is non-integer with some pesky decimals (i.e. 33.12) and zinb / pscl doesn't like that - not surprising as zinb is for count data, normally whole integers etc. Does anyone know of a different zinb package that will allow non-integers or and equivalent test/ model to zin...

Dear all.. I have a respon variable y. Predictor variable are x1, x2, x3, x4, x5 (1) What is the syntax to get paramater estimation of ZINB Model by Newton Raphson (not BFGS) (2) What syntax to plot probability of observed & predicted of ZINB Thx. Regards Krist. [[alternative HTML version deleted]]

Dear all, I am modeling the incidence of recreational anglers along a stretch of coastline, and with a vary large proportion of zeros (>80%) have chosen to use a zero inflated negative binomial (ZINB) distribution. I am using the same variables for both parts of the model, can anyone help me with R code to compute overall marginal effects of each variable? My model is specified as follows: ZINB <- zeroinfl(Tot.Anglers ~ Location + Season + Daytype + Holiday.not + CPUE + ShoreType + Access...

I want to generate 1,000 random samples of sample size=1,000 from ZINB. I know there is a rnegbin() to generate random samples from NB, and I know I can use the following process: do i=1 to 1000 n=0 do i=1 to 1000 if runi(1)>0.1 then x(i) = 0; else x(i)=rnegbin(); n=n+1; if n>1000 then stop; end; output; end; Anybody can help me out with the R code? Th...

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 HTML version deleted]]

Dear Mr.Zeileis & all. (1)     Thx for your reply. Yes, I am talk about the function zeroinfl() from the package "pscl". I want to use Newton Raphson to get parameter             estimation ZINB, so I try this: ----------------------------------------------------------------------------------------------------------------------------------         > zinb <- zeroinfl(y ~x1+x2+x3+x4+x5|x1+x2+x3+x4+x5, data = dat, link="logit",dist = "negbin", method="Newton Rap...

Dear users, Does anyone have any idea how to generate standardised beta coefficients for a ZINB model in R to compare which explanatory variables are having the greatest impact on the dependent variable? Thanks, Jeremy [[alternative HTML version deleted]]

Buenas tardes, Estoy estimando un modelo binomial negativo de ceros inflados (ZINB) utilizando el comando zeroinfl() del paquete pscl. Al ejecutarlo me da el siguiente aviso: Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred ¿Sabéis que significa y si puedo usar el modelo aún con ese aviso? ¿Los coeficientes son fiables? Muchas gracias, Miriam

Hi, I am Olga Viedma. I am running a Zero-inflated negative binomial (ZINB) multi-level model using MCMCglmm package. I have a doubt. Can I use the "Liab" outputs as fitted data, instead of the predicted values from "predict"? The liab outputs fit very well with the observed data, whereas the predicted values are so bad. Thanks in advance, Olga V...

Buenas tardes, ¿Cómo interpretarías el intercepto que da R en un modelo de ceros inflados? Por un lado en la parte de conteo tengo un intercepto de -4.2 y en la parte de ceros de 102, ambos salen significativos (***). ¿Qué me dirían? Gracias

Dear Sirs   First herewith I'll introduce myself. My name is Kristiono, I want ask you to help me how to get  ZINB (Zero Inflated Negative Binomial) regression modeling step by step. Anyway, I get some trouble to get step by step about 1.    How to get the log likelihood function of ZINB (step by step) 2.    How to get first derivative, second derifative to get MLE by Newton Raphson (step by step) 3.    Syntax...

...; > Un saludo, > > Carlos J. Gil Bellosta > http://www.datanalytics.com > > > > > El lun., 9 abr. 2018 a las 18:34, <miriam.alzate en unavarra.es> escribió: > >> Buenas tardes, >> >> Estoy estimando un modelo binomial negativo de ceros inflados (ZINB) >> utilizando el comando zeroinfl() del paquete pscl. Al ejecutarlo me da >> el >> siguiente aviso: >> Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred >> >> ¿Sabéis que significa y si puedo usar el modelo aún con ese aviso? ¿Los >> coefi...

I have not included the previous postings because they came out very strangely on my mail reader. However, the question concerned the choice of minimizer for the zeroinfl() function, which apparently allows any of the current 6 methods of optim() for this purpose. The original poster wanted to use Newton-Raphson. Newton-Raphson (or just Newton for simplicity) is commonly thought to be the

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, zinb) Error en predprob.glm(m1) :   your object of class glm is unsupported by predprob.glmyour object of class lm is unsupported by predprob.glm...

...t; > >> > >> > >> > >> > El lun., 9 abr. 2018 a las 18:34, <miriam.alzate en unavarra.es> >> escribió: >> > >> >> Buenas tardes, >> >> >> >> Estoy estimando un modelo binomial negativo de ceros inflados (ZINB) >> >> utilizando el comando zeroinfl() del paquete pscl. Al ejecutarlo me >> da >> >> el >> >> siguiente aviso: >> >> Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred >> >> >> >> ¿Sabéis que significa y...

...at models fits better. > vuong (model.poisson, model.zero.poisson) Is that correct? 5) ats.ucla.edu has a section about zero-inflated Poisson Regressions, and test the zeroinflated model (a) against the standard poisson model (b): > m.a <- zeroinfl(count ~ child + camper | persons, data = zinb) > m.b <- glm(count ~ child + camper, family = poisson, data = zinb) > vuong(m.a, m.b) I don't understand what the "| persons" part of the first model does, and why you can compare these models if. I had expected the regression to be the same and just use a different family....

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 = TRUE) summary(zinb) *Call: zeroinfl(formula = count ~ child + camper | persons, dist = "negbin", EM = TRUE) Count model coefficients (negbin with...

...> > El lun., 9 abr. 2018 a las 18:34, <miriam.alzate en unavarra.es> >> >> escribió: >> >> > >> >> >> Buenas tardes, >> >> >> >> >> >> Estoy estimando un modelo binomial negativo de ceros inflados >> (ZINB) >> >> >> utilizando el comando zeroinfl() del paquete pscl. Al ejecutarlo >> me >> >> da >> >> >> el >> >> >> siguiente aviso: >> >> >> Warning: glm.fit: fitted probabilities numerically 0 or 1 occurred >&...

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

...Lac : int 0 0 0 0 0 1 0 0 0 0 ... $ Scars : int 0 0 0 0 0 5 0 4 5 5 ... $ Lar : int 15 0 3 0 0 0 1 0 0 3 ... $ Mass : num 13.9 15.6 16.4 16.6 17.5 ... $ Lacfac : Factor w/ 2 levels "0","1": 1 1 1 1 1 2 1 1 1 1 ... The syntax I used to create the model is: zinb.zc <- zicounts(resp=Scars~.,x =~Location + Lar + Mass + Lar:Mass + Location:Mass,z =~Location + Lar + Mass + Lar:Mass + Location:Mass, data=alan) The error given is: Error in optim(par = parm, fn = neg.like, gr = neg.grad, hessian = TRUE, : non-finite value supplied by optim In addit...