search for: vuong

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"   wh...

Hi, I have two questions. First, I'd like to compare a ZINB model to a negativ binomial model with the Vuong test, but I can't find how to performe it from the zicount package. Does a programm exist to do it ? Second, I'd like to know in which cases we have to use a double hurdle model instead of a zero inflated model. Many thanks, St??phanie Payet REES France R??seau d'Evaluation en Econom...

Dear All, I am using the function vuong of the package pscl to compare 2 non nested glm models with a numeric response. I did the following m1<-glm(y ~x ,data=xxx) m2<-glm(y ~z , data=xxx) When calling the vuong function I get the following message: > vuong(m1,m2) Error in predprob.glm(m1) : your object of class glm is unsup...

...pare the poisson and the zero-inflated poisson distribution on describing the data. So, after using the GLM and the ZEROINFL function, I used the Voung function to compare them. Here is my code: library(pscl) glm1 <- glm(nmer9_1[, 1] ~ 1, family = poisson) zip <- zeroinfl(nmer9_1[, 1] ~ 1) vuong(glm1, zip) However, R returns the following error message: "Error: cannot allocate vector of size 3.3 Gb." Would you please tell me what was happening there? Please note that I am not trying to do a regression, but only want to compare which of the distributions explain the data better...

...ions? What test do I use to see whether 1) or 2) fits better - simply anova(m1,m2)? 3) I also read that negative-binomial distribution can be used when overdispersion appears. How do I do this in R? What is the difference to quasipoisson? 4) Zero-inflated Poisson Regression: I read that using the vuong test checks what 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 | p...

Dear All, I would like to know if the Voung test (Voung; Econometrica, 1989) to compare two non-nested regression models has been implemented in R. Thanks in advance for your assistance, mirko [[alternative HTML version deleted]]

Dear All, I am using the function vuong of the package pscl to compare 2 non nested glm models with a numeric response. I did the following m1<-glm(y ~x ,data=xxx) m2<-glm(y ~z , data=xxx) When calling the vuong function I get the following message: > vuong(m1,m2) Error in predprob.glm(m1) : your object of class glm is unsup...

...nt data" en R y estoy aplicando varios modelos: Quasi Poisson, Negative Binomial, Zero Inflated Models, Tobit y Tobit con Heckman. Me gustaría profundizar en la interpretación de los modelos (coeficientes y parámetros descriptivos de cada modelo) y los test de comparación entre ellos (Test de Vuong, Wald, Log likelihood...etc). ¿Recomendáis algún curso/taller (presencial o no) donde se incluyan estos temas? Muchas gracias por vuestra ayuda y sugerencias! ;) Que tengáis buen día, Lorena [[alternative HTML version deleted]]

Dear All, I fitted two non-nested proportional hazards models using the coxph() function from package survival. Now, I would like to apply a model selection test like, e.g., the likelihood ratio test proposed by Vuong. I found an implementation of Vuong's test in the package 'pscl', but that does not work for cox models. Is there any package available that provides an implementation of that test or can someone point me to an implementation of a similar test? Thanks in advance! Hans-Ulrich --...

Hi all, I have a problem. I want to call some function after every 10 minutes. But I don''t it. -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this

I am trying to implement an ANOVA on a pair of quantile regression models in R. The anova.rq() function performs a basic check to see whether the models are nested, but I think this check is failing in my case. I think my models are nested despite the anova.rqlist() function saying otherwise. Here is an example where the GLM ANOVA regards the models as nested, but the quantile regression ANOVA

...so we would expect an excess in zeroes. I have tested that the data are overdispersed (variance much bigger than mean), so a zero-inflated negative binomial model seems the most suitable model in this case. To be sure, I will compare the zero-inflated model to the standard binomial model using the vuong test. The models will be made for each species separately. For these models I can use the glm.nb(), and the and zeroinfl () in the package pscl, looking something like this (after selection of the subset B<-subset(data, Species=="B")): NB=glm.nb(formula = Count ~ District+Site+Survey,...

...os: Quasi Poisson, Negative > > Binomial, Zero Inflated Models, Tobit y Tobit con Heckman. > > > > Me gustar a profundizar en la interpretaci n de los modelos > > (coeficientes y par metros descriptivos de cada modelo) y los test de > > comparaci n entre ellos (Test de Vuong, Wald, Log likelihood...etc). > > > > Recomend is alg n curso/taller (presencial o no) donde se incluyan > > estos temas? > > > > Muchas gracias por vuestra ayuda y sugerencias! ;) > > > > Que teng is buen d a, > > > > Lorena > > > &gt...

Dear R users, Could somebody please help me to find a way of comparing nonlinear, non-nested models in R, where the number of parameters is not necessarily different? Here is a sample (growth rates, y, as a function of internal substrate concentration, x): x <- c(0.52, 1.21, 1.45, 1.64, 1.89, 2.14, 2.47, 3.20, 4.47, 5.31, 6.48) y <- c(0.00, 0.35, 0.41, 0.49, 0.58, 0.61, 0.71, 0.83, 0.98,

I have app RoR good running on NetBean with JRuby But, I upload up server to server, it not run. I have ready setup rubygem. Cau you help me? please guide detail with me about work from how to upload code to server host and start running app RoR. -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk"

Hi everybody, I have a problem: I want to insert a new column into a table (person, it ready exits in DB.). But i dont know to do what. Do yo have any idea to help me? Thank you for your reading. -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to

...hen there is the good chance that the error term e1 is correlated with y2*. Running polr (Y1 ~ Y2 + X1 +X2) in isolation might give badly biased estimates. I have found a well developed literature that deals with the question when one of the Y's is dichotomous. Rivers, Douglas and Quang H. Vuong. 1988. Limited Information Estimators and Exogeneity Tests for Simultaneous Probit Models. Journal of Econometrics 39: 347-366 Alvarez, R. Michael and Garrett Glasgow. 1999. Two-Stage Estimation of Nonrecursive Choice Models. Political Analysis. 8: 11:24. I have not found anybody who has estimate...

I have a problem when i am creating a rails project using postgresql... uninitialized constant ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::PGconn I have already installed gem postgres-pr. but not start.. I using rails version 2.3.5 Ruby 1.8.7 PostgresSQL 1.10.2. Please help me thanks. -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to