Angela, My guess is that your data are not balanced. That could be due to a typo in one of the factors, or it could be that you actually have different numbers of observations at some of the factor levels.
Rich On Sun, May 17, 2015 at 12:05 PM, Angela Radulescu <angela.radule...@gmail.com> wrote: > I have the following R output from a mixed factorial ANOVA: > > Error: subj > Df Sum Sq Mean Sq F value Pr(>F) group > 1 11.3 11.26 0.449 0.50811 > singleType 1 0.7 0.66 0.026 0.87220 group:singleType > 1 237.5 237.53 9.484 0.00461 **Residuals 28 701.3 25.04 > ---Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 > ‘.’ 0.1 ‘ ’ 1 > Error: subj:singleType > Df Sum Sq Mean Sq F value Pr(>F) > singleType 1 1566.4 1566.4 411.445 <2e-16 ***group:singleType > 1 3.4 3.4 0.893 0.352 Residuals 30 114.2 3.8 > ---Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 > ‘.’ 0.1 ‘ ’ 1 > Error: Within > Df Sum Sq Mean Sq F value Pr(>F)Residuals 3286 5747 1.749 > > Here "group" is the between factor (2 levels) and "singleType" the within > factor (2 levels). I'm not sure why there are two group:singleType > interaction terms. Any help would be much appreciated! > > For reference, here is the original aov call: > > anova.p = aov(data = dat.colSingle, rt ~ (group*singleType) + > Error(subj/singleType)) > summary(anova.p) > > Thank you! > > -- > Angela Radulescu > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.