No, it is an argument to createFolds. Type ?createFolds to see the appropriate syntax: "returnTrain a logical. When true, the values returned are the sample positions corresponding to the data used during training. This argument only works in conjunction with list = TRUE"
On Mon, Oct 3, 2011 at 11:10 AM, <bby2...@columbia.edu> wrote: > Hi Max, > > Thanks for the note. In your last paragraph, did you mean "in > createDataPartition"? I'm a little vague about what returnTrain option does. > > Bonnie > > Quoting Max Kuhn <mxk...@gmail.com>: > >> Basically, createDataPartition is used when you need to make one or >> more simple two-way splits of your data. For example, if you want to >> make a training and test set and keep your classes balanced, this is >> what you could use. It can also make multiple splits of this kind (or >> leave-group-out CV aka Monte Carlos CV aka repeated training test >> splits). >> >> createFolds is exclusively for k-fold CV. Their usage is simular when >> you use the returnTrain = TRUE option in createFolds. >> >> Max >> >> On Sun, Oct 2, 2011 at 4:00 PM, Steve Lianoglou >> <mailinglist.honey...@gmail.com> wrote: >>> >>> Hi, >>> >>> On Sun, Oct 2, 2011 at 3:54 PM, <bby2...@columbia.edu> wrote: >>>> >>>> Hi Steve, >>>> >>>> Thanks for the note. I did try the example and the result didn't make >>>> sense >>>> to me. For splitting a vector, what you describe is a big difference btw >>>> them. For splitting a dataframe, I now wonder if these 2 functions are >>>> the >>>> wrong choices. They seem to split the columns, at least in the few >>>> things I >>>> tried. >>> >>> Sorry, I'm a bit confused now as to what you are after. >>> >>> You don't pass in a data.frame into any of the >>> createFolds/DataPartition functions from the caret package. >>> >>> You pass in a *vector* of labels, and these functions tells you which >>> indices into the vector to use as examples to hold out (or keep >>> (depending on the value you pass in for the `returnTrain` argument)) >>> between each fold/partition of your learning scenario (eg. cross >>> validation with createFolds). >>> >>> You would then use these indices to keep (remove) the rows of a >>> data.frame, if that is how you are storing your examples. >>> >>> Does that make sense? >>> >>> -steve >>> >>> -- >>> Steve Lianoglou >>> Graduate Student: Computational Systems Biology >>> | Memorial Sloan-Kettering Cancer Center >>> | Weill Medical College of Cornell University >>> Contact Info: http://cbio.mskcc.org/~lianos/contact >>> >>> ______________________________________________ >>> 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. >>> >> >> >> >> -- >> >> Max >> >> > > > -- Max ______________________________________________ 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.
