Hi I had similar problem before and I ended with some ordering of groups before making grouped data object but it was data specific so I can not give you definite clue.
Regards Petr [EMAIL PROTECTED] napsal dne 08.10.2008 19:30:07: > Dea-R community. > > I'd like to draw your attention to an issue I have recently > encountered while doing my current data analysis. > > I've got an unexpected (to me) result from the command: > > > augPred(lmList(my.object)), > > 'my.object' being a grouped data frame of class: > > > class(my.object) > [1] "nfnGroupedData" "nfGroupedData" "groupedData" "data.frame" > > The problem is more easily explained by showing these two to Trellis > plot: > > > plot(my.object,some_options) > > plot(augPred(lmList(my.object)),some_options) > > [link to output: http://www.palug.net/Members/jabba ] > > Clearly the problem is that the predictions are correct, but the > responses in the ``original'' part of the augPred data frame are in the > wrong order, i.e. the response order does not match the grouping > factor order (not sure this is in correct English, sorry). > > Debugging the function 'augPred.lmList' I've managed to understand that > the problem resides in the following function calls: > > > debug(nlme:::augPred.lmList) > > fm1.lis <- lmList(my.object) > > augPred(fm1.lis) > debugging in: augPred.lmList(fm1.lis) > debug: { > ..... > primary <- getCovariate(data) > ..... > groups <- getGroups(object) > ..... > orig <- data.frame(primary,groups, getResponse(object)) > ..... > } > > This approach works well on other datasets, such us the Orthodont data, > but not for mine because, i guess, my rows are not first ordered by > subject (subject is my grouping factor). In fact: > > > getGroups(fm1.lis)[1:5] > [1] CBT.1 CBT.2 CBT.3 CBT.4 CBT.5 > 34 Levels: CBT.14 < CBT.2 < CBT.11 < CBT.13 < CBT.12 < CBT.5 < ... < V.6 > > getResponse(fm1.lis)[1:5] > CBT.1 CBT.1 CBT.1 CBT.1 CBT.2 > 34 32 29 27 28 > > My question: > is there a simple way to get the proper result (modify the dataset or > modify the function)? RTFM responses are welcomed. > > My (humble?) opinion: > Neither Pinheiro-Bates (2000) nor online documentation, report the > need for a particular row order in the costruction of grouped data > objects, and i think it should be better do not rely on it. Or, at > least, to document it somewhere. > > > I want to thank the R-core team and the entire R community for this > amazingly efficient and versatile software, and i am very proud that the > (not only) statistical state-of-the-art software have a ``gpl > distribution'' (which have many desirable properties ;-) ). > > Cheers. > > +---------------------------+ > |Relevant system information| > +---------------------------+ > > > R.version > _ > platform i486-pc-linux-gnu > arch i486 > os linux-gnu > system i486, linux-gnu > status > major 2 > minor 7.2 > year 2008 > month 08 > day 25 > svn rev 46428 > language R > version.string R version 2.7.2 (2008-08-25) > > > sessionInfo() > R version 2.7.2 (2008-08-25) > i486-pc-linux-gnu > > locale: > LC_CTYPE=it_IT;LC_NUMERIC=C;LC_TIME=it_IT;LC_COLLATE=it_IT;LC_MONETARY=C;LC_MESSAGES=it_IT;LC_PAPER=it_IT;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=it_IT;LC_IDENTIFICATION=C > > attached base packages: > [1] stats graphics grDevices utils datasets methods > base > > other attached packages: > [1] MASS_7.2-44 lattice_0.17-15 nlme_3.1-89 > > loaded via a namespace (and not attached): > [1] grid_2.7.2 tools_2.7.2 > > > -- > Marco Barbàra > > - Undergraduate student in Statistics > at the University of Palermo (Italy) > > - Only free-as-in-freedom software user > > - Emacs lover > > ______________________________________________ > 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.