Perhaps you display an object but forgot to load the package that ships
the summary method for the class of the object?
I guess
library("VGAM")
summary(RES_TOBIT)
should solve your problem.
BTW: Please always report which package you are talking about (vghlm is
not part of R base, obviously).
Uwe Ligges
On 03.02.2011 21:03, Hongwei Dong wrote:> Hi, dear R users,
>
> I'm running a Tobit regression and using "summary" to display
model results.
> It used to work. But this time, I kept getting this:
>
>> summary(RES_TOBIT)
>
> Length Class Mode
> 1 vglm S4
>
>
> Could anyone tell me how to solve this problem, and why I got this problem?
> Thanks.
>
>
> Gary
>
> [[alternative HTML version deleted]]
>
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