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 at 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 at r-project.org
> [mailto:r-help-bounces at r-project.org] Namens Edward Patzelt
> Verzonden: maandag 6 september 2010 15:43
> Aan: r-help at 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]]
>
> ______________________________________________
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> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
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