hello everybody I'm a newbie with ordered probit and with polr too. The problem is that I have a dependent variable I need to explain with an ordered probit that is
head(dfscale$sod.sit.ec.fam,100) [1] 5 7 5 6 5 5 6 8 6 8 8 8 6 6 6 5 0 5 NA 6 [21] 7 NA NA 0 0 2 5 3 6 6 7 6 NA 8 6 6 7 NA NA NA [41] 4 5 NA 10 3 9 10 10 7 5 5 5 NA NA 5 7 1 1 7 3 [61] 6 7 NA 4 6 NA 3 4 5 3 4 4 4 5 NA 2 4 4 8 5 [81] 5 4 6 6 5 6 7 7 7 7 7 6 8 7 6 5 5 5 6 7
so when I estimate the model
base.op <- polr(
as.ordered(sod.sit.ec.fam) ~
log(y) +
log(ncomp) +
eta +
I(eta^2) +
uomo +
elem +
laurea +
saluteno +
extra
,
weights = dfscale$w,
data = dfscale,
method = "probit"
)
I get
Warning in eval(expr, envir, enclos) : non-integer #successes in a binomial glm
Then when I try to summarize the model, in order to use xtable
summary(base.op)
Re-fitting to get Hessian
Errore in optim(start, fmin, gmin, method = "BFGS", hessian = Hess, ...) : valore iniziale in 'vmmin' non finito
that freely translated to english means "starting value in 'vmmin' not finished (or finite, more likely)" what does this mean? How can I have my summary? Thank you Luca
Luca Braglia, aka Bragliozzo
http://bragliozzo.altervista.org