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repeated measures ANOVA

Christian,
   You need, first to factor() your factors in the data frame P.PA,  
and then denote the error-terms in aov correctly, as follows:

 > group <- rep(rep(1:2, c(5,5)), 3)
 > time <- rep(1:3, rep(10,3))
 > subject <- rep(1:10, 3)
 > p.pa <- c(92, 44, 49, 52, 41, 34, 32, 65, 47, 58, 94, 82, 48, 60, 47,
+ 46, 41, 73, 60, 69, 95, 53, 44, 66, 62, 46, 53, 73, 84, 79)
 > P.PA <- data.frame(subject, group, time, p.pa)

 > # added code:
 > P.PA$group=factor(P.PA$group)
 > P.PA$time=factor(P.PA$time)
 > P.PA$subject=factor(P.PA$subject)

 > summary(aov(p.pa~group*time+Error(subject/time),data=P.PA))

Error: subject
           Df Sum Sq Mean Sq F value Pr(>F)
group      1  158.7   158.7  0.1931  0.672
Residuals  8 6576.3   822.0

Error: subject:time
            Df  Sum Sq Mean Sq F value   Pr(>F)
time        2 1078.07  539.03  7.6233 0.004726 **
group:time  2  216.60  108.30  1.5316 0.246251
Residuals  16 1131.33   70.71
---
Signif. codes:  0 ?***? 0.001 ?**? 0.01 ?*? 0.05 ?.? 0.1 ? ? 1
On 28-Feb-06, at 4:00 AM, r-help-request at stat.math.ethz.ch wrote:

            
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