[R] nlme Output

[ONKELINX, Thierry]

Dear Edward,

You have no degrees of freedom left to estimate those p-values. Your
design does not allows for the model your implemented. We need a brief
summary of your design in order to help you further.

HTH,

Thierry

------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek
team Biometrie & Kwaliteitszorg
Gaverstraat 4
9500 Geraardsbergen
Belgium

Research Institute for Nature and Forest
team Biometrics & Quality Assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium

tel. + 32 54/436 185
Thierry.Onkelinx op inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to
say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of
data.
~ John Tukey
  

> -----Oorspronkelijk bericht-----
> Van: r-help-bounces op r-project.org 
> [mailto:r-help-bounces op r-project.org] Namens Edward Patzelt
> Verzonden: maandag 6 september 2010 15:43
> Aan: r-help op r-project.org
> Onderwerp: [R] nlme Output
> 
> Everyone -
> 
> What do the NaN's mean here?  Is this analysis a problem?
> 
> 
> Linear mixed-effects model fit by maximum likelihood
>  Data: tmp.dat
>        AIC      BIC    logLik
>   1611.251 1638.363 -797.6253
> 
> Random effects:
>  Formula: ~1 | group_id
>          (Intercept) Residual
> StdDev: 0.0003077668 9.236715
> 
> Fixed effects: AvgTrials ~ time + factor(group_id) + time *
> factor(group_id)
>                            Value Std.Error  DF   t-value p-value
> (Intercept)            18.159722  3.576664 213  5.077279  0.0000
> time                    4.192708  1.655674 213  2.532327  0.0121
> factor(group_id)2      -6.929563  5.235700   0 -1.323522     NaN
> factor(group_id)3      -1.654554  4.189575   0 -0.394922     NaN
> time:factor(group_id)2  1.729911  2.423658 213  0.713760  0.4762
> time:factor(group_id)3 -2.555111  1.939396 213 -1.317478  0.1891
>  Correlation:
>                        (Intr) time   fc(_)2 fc(_)3 t:(_)2
> time                   -0.926
> factor(group_id)2      -0.683  0.632
> factor(group_id)3      -0.854  0.790  0.583
> time:factor(group_id)2  0.632 -0.683 -0.926 -0.540
> time:factor(group_id)3  0.790 -0.854 -0.540 -0.926  0.583
> 
> Standardized Within-Group Residuals:
>        Min         Q1        Med         Q3        Max
> -1.8842754 -0.6979785 -0.3370998  0.5666704  3.0943948
> 
> Number of Observations: 219
> Number of Groups: 3
> Warning message:
> In pt(q, df, lower.tail, log.p) : NaNs produced
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help op r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

Druk dit bericht a.u.b. niet onnodig af.
Please do not print this message unnecessarily.

Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer 
en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is
door een geldig ondertekend document. The views expressed in  this message 
and any annex are purely those of the writer and may not be regarded as stating 
an official position of INBO, as long as the message is not confirmed by a duly 
signed document.