[R-sig-ME] glmmADMB: Error in UseMethod(

[Lorenzo Quaglietta]

Ben Bolker <bbolker at ...> writes:

> 
> Isa Blasco <isa.blasco.costa at ...> writes:
> 
> > 
> > Hi,
> > I am using glmmADMB to fit a negative binomial model to my data. My
> > explanatory variable is an ordered factor with 10 levels and I also
> > included a random factor (numeric) and Zero inflation.
> > This is the code I used: m7 <- glmmadmb (abun~odist + (1|sl), data=apa,
> > zeroInflation=TRUE, family="nbinom")
> > 
> > When I run it I got this error:
> > Error in UseMethod("droplevels") :
> >   no applicable method for 'droplevels' applied to an object of class
> > "c('double', 'numeric')"
> > 
> > I do not know what the 'double' means but I checked the glmmADMB manual and
> > they use the same kind of variables in their example. Any guess on what it
> > is happening? How can I solve it?
> > I hope somebody knows!
> 
>   It means that it doesn't make sense to use a numeric variable as
> a grouping variable for a random factor (which is what you've done):
> if sl is a discrete numeric code that identifies groups of observations,
> then you should convert it to a factor.  If it's a continuous variable,
> then you need to go back and read/think some more about the meanings
> of random factors ...
> 
>   It also means that I made some changes to glmmADMB recently that
> got in the way of an informative error message (you should have
> received an error message that told you this).  I will try to 
> catch that error in a more informative way.
> 
>   Ben Bolker
> 
> 


Hi,

I'm having  a similar problem.

My model formula is:

glmmADMB1 <- glmmadmb(Fix ~ log_BIO_F * log_BIO_P + log_drs + fperp + log_pr +
log_la + (1 | ANIMALE) + (1 | ID) + (1 | Time), data=otters, zeroInflation=TRUE,
family="poisson").

and I got the following error message:

"Error in UseMethod("droplevels") : 
  no applicable method for 'droplevels' applied to an object of class
"c('integer', 'numeric')".

My random terms are not categorical nor fitted as factors. Which could be the
problem?

Many thanks in advance, best regards,

Lorenzo Quaglietta