What do you think is the correct answer and on what authority? (These are explicitly sequential aka Type 1 anova tables.)
That the SSqs depend on the order of fitting is a feature of an unbalanced design. I believe that R is correct and your understanding is not. On Thu, 29 Jul 2004 [EMAIL PROTECTED] wrote: > Full_Name: Tanya Logvinenko > Version: 1.7.0 Oh, please! Don't send in bug reports from very old versions -- there have been 5 releases since then. > OS: Windows 2000 > Submission from: (NULL) (132.183.156.125) > > > For unbalanced design, I ran into problem with ANOVA (aov function). The sum of > squares for only for the second factor and total are computed correctly, but sum > of squares for the first factor is computed incorreclty. Changing order of > factors in the formula changes the ANOVA table. For the balanced design, there > is no such problem. > > > summary(aov(data[1,]~factor1+factor2)) > Df Sum Sq Mean Sq F value Pr(>F) > factor1 5 1524420 304884 6.4529 0.0003229 *** > factor2 7 1447830 206833 4.3776 0.0017808 ** > Residuals 31 1464674 47248 > --- > Signif. codes: 0 `***' 0.001 `**' 0.01 `*' 0.05 `.' 0.1 ` ' 1 > > summary(aov(data[1,]~factor2+factor1)) > Df Sum Sq Mean Sq F value Pr(>F) > factor2 7 1648225 235461 4.9836 0.0007295 *** > factor1 5 1324025 264805 5.6046 0.0008612 *** > Residuals 31 1464674 47248 > --- > Signif. codes: 0 `***' 0.001 `**' 0.01 `*' 0.05 `.' 0.1 ` ' 1 The FAQ has a section on BUGS asking for a *reproducible* example. This is not. -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-devel
