From: Stephen Liu > > Hi JesperHybel, > > Thanks for your advice. > > >If you're trying to follow the youtube video you have a > typing mistake here: > > >InsectSprays.aov <-(test01$count ~ test01$spray) > > >I think this should be: > > >InsectSprays.aov <-aov(test01$count ~ test01$spray) > > > Your advice works for me. Sorry I missed "aov" before(test01$count ~ > test01$spray)
I just want to offer another point: If you see any tutorial/document/book advising you to use model formula as above; e.g., anything like df$var1 ~ df$var2 + df$var3 Just run away from it as fast as you can, and try to wipe it from your memory. That's about the worst way to use a model formula, and very likely to give you what may seem to be strange problems down the road. Well-written model fitting functions should be called like this: modelfn(var1 ~ var2 + var3, data=df, ...) Andy > > InsectSprays.aov <- aov(test01$count ~ test01$spray) > > summary(InsectSprays.aov) > Df Sum Sq Mean Sq F value Pr(>F) > test01$spray 5 2668.8 533.77 34.702 < 2.2e-16 *** > Residuals 66 1015.2 15.38 > --- > Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 > > > > TukeyHSD(InsectSprays.aov) > Tukey multiple comparisons of means > 95% family-wise confidence level > > Fit: aov(formula = test01$count ~ test01$spray) > > $`test01$spray` > diff lwr upr p adj > B-A 0.8333333 -3.866075 5.532742 0.9951810 > C-A -12.4166667 -17.116075 -7.717258 0.0000000 > D-A -9.5833333 -14.282742 -4.883925 0.0000014 > E-A -11.0000000 -15.699409 -6.300591 0.0000000 > F-A 2.1666667 -2.532742 6.866075 0.7542147 > C-B -13.2500000 -17.949409 -8.550591 0.0000000 > D-B -10.4166667 -15.116075 -5.717258 0.0000002 > E-B -11.8333333 -16.532742 -7.133925 0.0000000 > F-B 1.3333333 -3.366075 6.032742 0.9603075 > D-C 2.8333333 -1.866075 7.532742 0.4920707 > E-C 1.4166667 -3.282742 6.116075 0.9488669 > F-C 14.5833333 9.883925 19.282742 0.0000000 > E-D -1.4166667 -6.116075 3.282742 0.9488669 > F-D 11.7500000 7.050591 16.449409 0.0000000 > F-E 13.1666667 8.467258 17.866075 0.0000000 > > > I made a comparison of my result with "example(InsectSprays). > They looks the > same. > > I also compared "plot(InsectSprays.aov)". > > > A further question how to plot 4 graphs simultaneously? > Instead of reading > them, individually. I read ?plot but unable to resolve. > > Also how to save InsectSprays.aov? I think I can only save it as > InsectSprays.csv. I can't find "write.aov" command. > > > Thanks > > > TIA > > B.R. > satimis > > > > > > > ----- Original Message ---- > From: JesperHybel <jesperhy...@hotmail.com> > To: r-help@r-project.org > Sent: Sat, August 14, 2010 2:09:48 AM > Subject: Re: [R] Learning ANOVA > > > If you're trying to follow the youtube video you have a > typing mistake here: > > InsectSprays.aov <-(test01$count ~ test01$spray) > > I think this should be: > > InsectSprays.aov <-aov(test01$count ~ test01$spray) > > > youre missing the functioncall "aov" on the right hand side of the > assignment operator '<-'. > > the results of the application of function aov() is stored in > InsectSprays.aov and is accessed through > > summary(InsectSprays.aov) > > since you missed the functioncall you cannot apply TukeyHSD() to > InsectSprays.aov > > I think > -- > View this message in context: > http://r.789695.n4.nabble.com/Learning-ANOVA-tp2323660p2324590.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > 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 > 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. > Notice: This e-mail message, together with any attachme...{{dropped:11}} ______________________________________________ R-help@r-project.org mailing list 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.
