[R] NB1 with glm.nb?

Dear Dr. Schwartz,   I would like to ask you if you know how to fit NB1 with glm.nb(...), because glm.nb() is actually fitting NB2.   Thanks so much   Ana > > De: Marc Schwartz >Para: sanchez ana >CC: "r-help@R-project.org" >Envi

[R] NaN in hurdle model please?

Dear all, I am fitting  a hurdle model in the following way: HNB <- hurdle(chro ~ as.factor(TandemRepeat)| as.factor(TandemRepeat), data =data_negbin_fin, dist = "negbin") But the std. error for log(theta) = NA Count model coefficients (truncated negbin with log link):    

[R] Hurdle "NaN" for log(theta)

ks so much   Ana > > De: Marc Schwartz >Para: sanchez ana >CC: "r-help@R-project.org" >Enviado: Viernes, 13 de julio, 2012 7:36:26 >Asunto: Re: [R] Vuong test > > >On Jul 13, 2012, at 12:35 AM, sanchez ana wrote: > >> Dear All, >> >&g

Re: [R] Vuong test

Dear Dr. Schwartz,   Thanks so much   Ana > > De: Marc Schwartz >Para: sanchez ana >CC: "r-help@R-project.org" >Enviado: Viernes, 13 de julio, 2012 7:36:26 >Asunto: Re: [R] Vuong test > > >On Jul 13, 2012, at 12:35

[R] 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 a

[R] sem R: singular and Could not compute QR decomposition of Hessian

Can somebody help me with the following issue (SEM in R), please:   When I run the model (includes second order models) in R, it gives me the following:   1)   In sem.default(ram = ram, S = S, N = N, param.names = pars, var.names = vars,  :   Could not compute QR decomposition of Hessian. Opt