[R-sig-ME] interpreting Std. error from glmer output

[William Morris]

Well, it depends.

It depends on what you mean by deviance, you should clarify this (here  
is a start http://en.wikipedia.org/wiki/Deviance_%28statistics%29). In  
general, deviance is used as a measure of model fit and usually  
encountered as a component of Information criteria.

Do you need to take the uncertainty (SE) in model estimates into  
account? It is probably a good idea if you are going to make  
predictions based on model estimates to also calculate predictions at  
the 95CI limits.

On 15/09/2009, at 10:26 PM, Christine Griffiths wrote:

> Thank you. So to clarify, I do not need to calculate the deviance of  
> the standard error from the intercept standard error, in the way  
> that I would do for the estimate?
>
> Cheers
> Christine
>
> --On 15 September 2009 21:38 +1000 Will Morris <wkmor1 at gmail.com>  
> wrote:
>
>> The SE is a measure of the models uncertainty about the parameter
>> estimates, it takes into account your sample size as well as sample
>> variance.  +_2*SE is usually a good estimate of the 95% confidence
>> interval.  In other words your treatment effect for treatment2 is
>> probably somewhere between -.6 and -.86.
>>
>>
>> On Tue, Sep 15, 2009 at 8:05 PM, Christine Griffiths
>> <Christine.Griffiths at bristol.ac.uk> wrote:
>>
>> I want to plot my predictions from a model and use the standard error
>> output as a measure of dispersion as I am unable to calculate  
>> confidence
>> intervals with mcmcsamp as I have a binomial distribution.
>>
>> I know that the estimates are deviations from the intercept.
>> Fixed effects below:
>>                          Estimate Std. Error z value Pr(>|z|)
>> (Intercept)                 2.90836    0.34041   8.544  < 2e-16 ***
>> treatment2                         -0.73507    0.12986  -5.660  
>> 1.51e-08
>> ***
>> treatment3                 -1.20052    0.12371  -9.705  < 2e-16 ***
>>
>> So the estimate for treatment 2 is 2.9 + -0.73. Are standard errors  
>> also
>> deviations from the intercept? i.e. 0.34 + 0.13 for treatment 2?
>>
>> Many thanks
>> Christine
>>
>> _______________________________________________
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>> https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models
>>
>>
>>
>>
>> --
>> Will Morris
>> Masters of Philosophy candidate
>> Vesk Plant Ecology Lab
>> The School of Botany
>> The University of Melbourne
>> Australia
>> Phone: +61 3 8344 0120
>> http://www.botany.unimelb.edu.au/vesk/
>
>
>
> ----------------------
> Christine Griffiths
> PhD student
> School of Biological Sciences
> University of Bristol
> Woodland Road
> Bristol BS8 1UG
> Tel: 0117 9287593
> Fax 0117 3317985
> Christine.Griffiths at bristol.ac.uk
> http://www.bio.bris.ac.uk/research/mammal/tortoises.html



Will Morris
Masters of Philosophy candidate
Vesk Plant Ecology Lab
The School of Botany
The University of Melbourne
Australia
Phone: +61 3 8344 0120
http://www.botany.unimelb.edu.au/vesk/