Hi Chris,
Thanks for your advice which works for me here. I'm reading; An Introduction to R http://h1.mg4.mail.yahoo.com/dc/launch?sysreq=ignore NOT finish yet. Also I found many tutorials on Internet. I'll take me time going through all of them. I'm interesting reading tutorial with demo. Otherwise it won't be easy for a beginning remembering all commands and steps on manual. B.R. Stephen L ----- Original Message ---- From: Christopher W Ryan <cr...@binghamton.edu> To: R-help@r-project.org Sent: Sat, August 14, 2010 1:51:34 AM Subject: Re: [R] Learning ANOVA Read documentation for TukeyHSD by typing the command: ?TukeyHSD The input to that function should usually be, "a fitted model object, usually an aov fit." You have not created a "fitted model object." This seems to work: model <- aov(InsectSprays$count ~ InsectSprays$spray) TukeyHSD(model) The aov() makes the aov model object. Tacking .aov onto an object name doesn't do that. Which introductory R book(s) have you read? That would be a worthwhile investment of your time. --Chris Ryan On Fri, Aug 13, 2010 at 12:43 PM, Stephen Liu <sati...@yahoo.com> wrote: > Hi Erik, > > > I followed following video as example; > > ANOVA in R > http://www.youtube.com/watch?v=Dwd3ha0P8uw&feature=related > > > Now I got it done; > > > boxplot(test01$count ~ test01$spray) > > > Continued: > > > InsectSprays.aov <-(test01$count ~ test01$spray) > > summary(InsectSprays.aov) > Length Class Mode > 3 formula call > > Seems having problem here. > > > > TukeyHSD(InsectSprays.aov) > Error in UseMethod("TukeyHSD") : > no applicable method for 'TukeyHSD' applied to an object of class > "formula" > > I'm still stuck here. > > > B.R. > Stephen L > > > > > ----- Original Message ---- > From: Erik Iverson <er...@ccbr.umn.edu> > To: Stephen Liu <sati...@yahoo.com> > Cc: r-help@r-project.org > Sent: Sat, August 14, 2010 12:15:31 AM > Subject: Re: [R] Learning ANOVA > > > > > Performed following steps on R:- > > > > ### to access to the object > >> data(InsectSprays) > > > > ### create a .csv file > >> write.csv(InsectSprays, "InsectSpraysCopy.csv") > > > > > > On another terminal > > $ sudo updatedb > > $ locate InsectSpraysCopy.csv > > /home/userA/InsectSpraysCopy.csv > > > > > > ### Read in some data > >> test01 <- read.csv(file.choose(), header=TRUE) > > > > Enter file name: /home/userA/InsectSpraysCopy.csv > > I either don't understand what you're doing, or you seem > very confused. > > R comes with many sample data sets for you to use. > > You can see a list of them using the ?data function. > > Calling data with an argument loads that dataset. > > So, when you type: > > > data(InsectSprays) > > that data object is now available in R, see > > > objects() > > You can look at it simply by printing it: > > > InsectSprays > > If for some reason it makes sense to do it this way for your > use case, then that's fine, I just want to make sure you understand > that you don't have to if accessing built-in datasets is all you want. > > > ### Look at the data > >> test01 > > X count spray > > 1 1 10 A > > 2 2 7 A > > 3 3 20 A > > <snip> > > > ### Create a side-by-side boxplot of the data > > boxplot(test01$DO ~ test01$Stream) > > Error in model.frame.default(formula = test01$DO ~ test01$Stream) : > invalid > >type (NULL) for variable 'test01$DO' > > Why do you think test01 has an element called "D0" or "Stream"?? The > column names when you print the data tell you otherwise! > > > > ______________________________________________ > 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<http://www.r-project.org/posting-guide.html> >> > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ 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.