[R] Strange glm(, quasipoisson) error

[Wil M Contreras Arbaje]

PS.:  I tried the following solution http://markmail.org/message/353xeiqtqj6jwxsx 
, which basically rewrites the quasipoisson to 'obviate' negative  
values (when using that code, I assigned it to quasipoisson2, just in  
case). Either way, I got a different error, which suggests that  
something else is going on...

Error in if (!(validmu(mu) && valideta(eta))) stop("cannot find valid  
starting values: please specify some",  :
   missing value where TRUE/FALSE needed
In addition: Warning message:
In mean.default(y) : argument is not numeric or logical: returning NA

Don't know if it helps...


On Oct 19, 2010, at 00:55 , Wil M Contreras Arbaje wrote:

> Dear list,
>
> I have recently encountered an odd error when running glm(dep~indep,  
> quasipoisson): while, with a subset of my data, I could get a  
> perfectly reasonable model, once I include all of my data (17K+  
> observations, 29 variables), I get the following error:
>
> Error in if (any(y < 0)) stop("negative values not allowed for the  
> quasiPoisson family") :
>  missing value where TRUE/FALSE needed
> In addition: Warning message:
> In Ops.factor(y, 0) : < not meaningful for factors
>
> I say this is odd because I triple checked my response variable, and  
> not a single observation is negative. Is R encountering an error due  
> to the size of the data, and somehow returning a 'random' error?  
> (would be stranger still!)
>
> Thanks a million, hope this makes sense.
>
> Cheers,
>
>
> Wil