Dear all,

Sorry, for this question, but I'm quite new to R and statestic. I have tried
to search the help options without any sucess.

I use lme(), and the anova method to test for differences between groups, se
below (as described at page 224 and 225 in Mixed-Effects Models in S and
S-PLUS, by Pinhiro and Bates). It works well, and I'm considering to
use this test in an article.

My problem is that I'm not sure how this lme () and anova method should be
exactly reported in the method chapter? If I have understood it right, the
anova is not an ordinary anova, but a anova test between categories selected
by the lme() model?

And what values should be mentioned from the test in the result chapter? Is
it appropriate to report the parameter estimates from lme() or should I only
report anova(lme)?


Respons: Speed
Fixed effects: Fuel, CarMod (1,2&3)
Random effects: Place

> lme1 <- lme(Speed ~  Fuel*Car, random=~1|Place,data=test)
> summary (lme1)
Linear mixed-effects model fit by REML
Data: test
      AIC      BIC    logLik
261.2013 275.6996 -121.6007

Random effects:
Formula: ~1 | Place
           (Intercept)         Residual
StdDev: 0.0003238738   5.013858

Fixed effects: Speed ~ Fuel + Car + Driver + Fuel * Car
                      Value        Std.Error     DF   t-value       p-value
(Intercept)        -29.33479  12.743084   30   -2.302017   0.0285
Fuel                10.04684    1.408789    30    7.131542   0.0000
CarMod2         46.55593    14.192029   7     3.280428   0.0135
CarMod3          1.65157     18.247158   7     0.090511   0.9304
Fuel:CarMod2  -5.53264     1.624159    30   -3.406464   0.0019
Fuel:CarMod3  -0.18452      2.010470   30   -0.091779   0.9275

Number of Observations: 44
Number of Groups: 10

> anova ( lme1, L = c("Fuel:CarMod2 " = 1, "Fuel:CarMod3" =-1))
F-test for linear combination(s)
        Fuel:CarMod2            Fuel:CarMod3
                      1                      -1
    numDF     denDF          F-value        p-value
1     1            30           0.4467829         0.0122

Regards R.S Cotter

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