[R] negative AIC and BIC values in gls

[Bert Gunter]

O course! And for the same reason, my stupid comment should be ignored.

-- Bert

On Thu, Aug 23, 2012 at 12:02 AM, Ingmar Visser <i.visser at uva.nl> wrote:
>> It's fine. Just interpret them as you would any other (lower is better).
>>>
>>>
>> And it is the printed logLik that is out of step here. log-likelihoods
>> _should_ be negative.
>>
>
> That is not quite the case; in models with small variances log-likelihoods
> can easily become positive, consider eg:
>
>> dnorm(0,0,0.1,log=T)
> [1] 1.383647
>
> hth, Ingmar
>
>
>
>> --
>> David.
>>
>>
>>> On 22 August 2012 16:43, Gary Dong <pdxgary163 at gmail.com> wrote:
>>>
>>>> Dear R users,
>>>>
>>>> I obtained negative AIC and BIC and positive Loglik values in a gls
>>>> model.
>>>> Is this normal? how should I interpret them? Thanks!
>>>>
>>>>       AIC       BIC           logLik
>>>>  -659.978  -587.5541   345.989
>>>>
>>>> Best
>>>> Gary
>>>>
>>>
>>
>> David Winsemius, MD
>> Alameda, CA, USA
>>
>>
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>>
>
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>
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-- 

Bert Gunter
Genentech Nonclinical Biostatistics

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