Dear colleagues, I teach statistics using SPSS. I want to use R instead. I hit on one problem and I need some quick advice. When I want to work with ordinal variables, in SPSS I can compute the median or create a barchart or compute a spearman correlation with no problems. In R, if I "read" the ordinal variable as numeric, then I cannot do a barplot because I miss the category names. If I read the variables as characters, then I cannot run a spearman. How can I read a variable as numeric, still have the chance to assign value labels, and be able to get table of frequencies etc? I want to be able to do all these things in R commander. My students will probable be scared away if I try anything else other than R commander (just writing commands will not make them happy). I hope I am not asking for too much. Hopefully there is a way
see ?factor and ?as.factor. On ordered factors you can technically do a
spearman without problem, apart from the fact that a spearman test by
definition cannot give exact p-values with ties present.
x <-
sample(c("a","b","c","d","e"),100,replace=T)
y <-
sample(c("a","b","c","d","e"),100,replace=T)
x.ordered <-
factor(x,levels=c("e","b","a","d","c"),ordered=T)
x.ordered
y.ordered <-
factor(y,levels=c("e","b","a","d","c"),ordered=T)
y.ordered
cor.test(x.ordered,y.ordered,method="spearman")
require(pspearman)
spearman.test(x.ordered,y.ordered)
R commander has some menu options to deal with factors. R commander also
provides a scripting window. Please do your students a favor, and show them
how to use those commands.
Cheers
Joris
On Thu, Jun 3, 2010 at 2:25 PM, Iasonas Lamprianou
<lamprianou@yahoo.com>wrote:
> Dear colleagues,
>
> I teach statistics using SPSS. I want to use R instead. I hit on one
> problem and I need some quick advice. When I want to work with ordinal
> variables, in SPSS I can compute the median or create a barchart or compute
> a spearman correlation with no problems. In R, if I "read" the
ordinal
> variable as numeric, then I cannot do a barplot because I miss the category
> names. If I read the variables as characters, then I cannot run a spearman.
> How can I read a variable as numeric, still have the chance to assign value
> labels, and be able to get table of frequencies etc? I want to be able to
do
> all these things in R commander. My students will probable be scared away
if
> I try anything else other than R commander (just writing commands will not
> make them happy).
>
> I hope I am not asking for too much. Hopefully there is a way
>
>
>
>
> ______________________________________________
> 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.
>
--
Joris Meys
Statistical Consultant
Ghent University
Faculty of Bioscience Engineering
Department of Applied mathematics, biometrics and process control
Coupure Links 653
B-9000 Gent
tel : +32 9 264 59 87
Joris.Meys@Ugent.be
-------------------------------
Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php
[[alternative HTML version deleted]]
If you set them a problem that has them doing the same sort of thing five times and compare the time it takes with code pasted from an editor (eg Tinn-R) and the time it takes via menius, you may have more luck convincing them. A command line sequence is harder than menus the first two times but easier for any n iterations thereafter. Steve ellison>>> Iasonas Lamprianou <lamprianou at yahoo.com> 03/06/2010 14:51 >>>Thank you Joris, I'll have a look into the commands you sent me. They look convincing. I hope my students will also see them in a positive way (although I can force them to pretend that they have a positive attitude)! Dr. Iasonas Lamprianou Assistant Professor (Educational Research and Evaluation) Department of Education Sciences European University-Cyprus P.O. Box 22006 1516 Nicosia Cyprus Tel.: +357-22-713178 Fax: +357-22-590539 Honorary Research Fellow Department of Education The University of Manchester Oxford Road, Manchester M13 9PL, UK Tel. 0044 161 275 3485 iasonas.lamprianou at manchester.ac.uk --- On Thu, 3/6/10, Joris Meys <jorismeys at gmail.com> wrote: From: Joris Meys <jorismeys at gmail.com> Subject: Re: [R] ordinal variables To: "Iasonas Lamprianou" <lamprianou at yahoo.com> Cc: r-help at r-project.org Date: Thursday, 3 June, 2010, 14:35 see ?factor and ?as.factor. On ordered factors you can technically do a spearman without problem, apart from the fact that a spearman test by definition cannot give exact p-values with ties present. x <- sample(c("a","b","c","d","e"),100,replace=T) y <- sample(c("a","b","c","d","e"),100,replace=T) x.ordered <- factor(x,levels=c("e","b","a","d","c"),ordered=T) x.ordered y.ordered <- factor(y,levels=c("e","b","a","d","c"),ordered=T) y.ordered cor.test(x.ordered,y.ordered,method="spearman") require(pspearman) spearman.test(x.ordered,y.ordered) R commander has some menu options to deal with factors. R commander also provides a scripting window. Please do your students a favor, and show them how to use those commands. Cheers Joris On Thu, Jun 3, 2010 at 2:25 PM, Iasonas Lamprianou <lamprianou at yahoo.com> wrote: Dear colleagues, I teach statistics using SPSS. I want to use R instead. I hit on one problem and I need some quick advice. When I want to work with ordinal variables, in SPSS I can compute the median or create a barchart or compute a spearman correlation with no problems. In R, if I "read" the ordinal variable as numeric, then I cannot do a barplot because I miss the category names. If I read the variables as characters, then I cannot run a spearman. How can I read a variable as numeric, still have the chance to assign value labels, and be able to get table of frequencies etc? I want to be able to do all these things in R commander. My students will probable be scared away if I try anything else other than R commander (just writing commands will not make them happy). I hope I am not asking for too much. Hopefully there is a way ______________________________________________ R-help at 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. -- Joris Meys Statistical Consultant Ghent University Faculty of Bioscience Engineering Department of Applied mathematics, biometrics and process control Coupure Links 653 B-9000 Gent tel : +32 9 264 59 87 Joris.Meys at Ugent.be ------------------------------- Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php [[alternative HTML version deleted]] ______________________________________________ R-help at 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. ******************************************************************* This email and any attachments are confidential. Any use...{{dropped:8}}
Thanks, I'll have a go and will let you know. I guess that the success has to do with how efficiently I help them to demonstrate the efficiency of code over menues. So part of the issue is how I teach them as well... Dr. Iasonas Lamprianou Assistant Professor (Educational Research and Evaluation) Department of Education Sciences European University-Cyprus P.O. Box 22006 1516 Nicosia Cyprus Tel.: +357-22-713178 Fax: +357-22-590539 Honorary Research Fellow Department of Education The University of Manchester Oxford Road, Manchester M13 9PL, UK Tel. 0044 161 275 3485 iasonas.lamprianou at manchester.ac.uk --- On Thu, 3/6/10, S Ellison <S.Ellison at lgc.co.uk> wrote:> From: S Ellison <S.Ellison at lgc.co.uk> > Subject: Re: [R] ordinal variables > To: "Joris Meys" <jorismeys at gmail.com>, "Iasonas Lamprianou" <lamprianou at yahoo.com> > Cc: r-help at r-project.org > Date: Thursday, 3 June, 2010, 15:44 > If you set them a problem that has > them doing the same sort of thing > five times and compare the time it takes with code pasted > from an editor > (eg Tinn-R) and the time it takes via menius, you may have > more luck > convincing them. > > A command line sequence is harder than menus the first two > times but > easier for any n iterations thereafter. > > Steve ellison > > >>> Iasonas Lamprianou <lamprianou at yahoo.com> > 03/06/2010 14:51 >>> > Thank you Joris, > I'll have a look into the commands you sent me. They look > convincing. I > hope my students will also see them in a positive way > (although I can > force them to pretend that they have a positive attitude)! > > Dr. Iasonas Lamprianou > > > > > > Assistant Professor (Educational Research and Evaluation) > > Department of Education Sciences > > European University-Cyprus > > P.O. Box 22006 > > 1516 Nicosia > > Cyprus > > Tel.: +357-22-713178 > > Fax: +357-22-590539 > > > > > > Honorary Research Fellow > > Department of Education > > The University of Manchester > > Oxford Road, Manchester M13 9PL, UK > > Tel. 0044? 161 275 3485 > > iasonas.lamprianou at manchester.ac.uk > > > --- On Thu, 3/6/10, Joris Meys <jorismeys at gmail.com> > wrote: > > From: Joris Meys <jorismeys at gmail.com> > Subject: Re: [R] ordinal variables > To: "Iasonas Lamprianou" <lamprianou at yahoo.com> > Cc: r-help at r-project.org > > Date: Thursday, 3 June, 2010, 14:35 > > see ?factor and ?as.factor. On ordered factors you can > technically do a > spearman without problem, apart from the fact that a > spearman test by > definition cannot give exact p-values with ties present. > > x <- sample(c("a","b","c","d","e"),100,replace=T) > > y <- sample(c("a","b","c","d","e"),100,replace=T) > > x.ordered <- > factor(x,levels=c("e","b","a","d","c"),ordered=T) > > x.ordered > y.ordered <- > factor(y,levels=c("e","b","a","d","c"),ordered=T) > y.ordered > > cor.test(x.ordered,y.ordered,method="spearman") > > require(pspearman) > > spearman.test(x.ordered,y.ordered) > > R commander has some menu options to deal with factors. R > commander > also provides a scripting window. Please do your students a > favor, and > show them how to use those commands. > > > Cheers > Joris > > > On Thu, Jun 3, 2010 at 2:25 PM, Iasonas Lamprianou > <lamprianou at yahoo.com> > wrote: > > Dear colleagues, > > > > I teach statistics using SPSS. I want to use R instead. I > hit on one > problem and I need some quick advice. When I want to work > with ordinal > variables, in SPSS I can compute the median or create a > barchart or > compute a spearman correlation with no problems. In R, if I > "read" the > ordinal variable as numeric, then I cannot do a barplot > because I miss > the category names. If I read the variables as characters, > then I cannot > run a spearman. How can I read a variable as numeric, still > have the > chance to assign value labels, and be able to get table of > frequencies > etc? I want to be able to do all these things in R > commander. My > students will probable be scared away if I try anything > else other than > R commander (just writing commands will not make them > happy). > > > > > I hope I am not asking for too much. Hopefully there is a > way > > > > > > > > > > ______________________________________________ > > R-help at 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. > > > > > -- > Joris Meys > Statistical Consultant > > Ghent University > Faculty of Bioscience Engineering > Department of Applied mathematics, biometrics and process > control > > > Coupure Links 653 > B-9000 Gent > > tel : +32 9 264 59 87 > Joris.Meys at Ugent.be > > ------------------------------- > Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php > > > > > > ? ? ? > ??? [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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. > > ******************************************************************* > This email and any attachments are confidential. Any use, > copying or > disclosure other than by the intended recipient is > unauthorised. If > you have received this message in error, please notify the > sender > immediately via +44(0)20 8943 7000 or notify postmaster at lgc.co.uk > > and delete this message and any copies from your computer > and network. > LGC Limited. Registered in England 2991879. > Registered office: Queens Road, Teddington, Middlesex, TW11 > 0LY, UK >