Hi John:

On Fri, Sep 10, 2010 at 11:40 AM, John Kane <jrkrideau@yahoo.ca> wrote:

> Are you trying to say that you don't really like barplots?????
>

Barplots are fine when they're used to display discrete distributions. The
problem comes when people begin to think it's an all-purpose graphic.

>
> At least the OP did not ask for error bars as well.  :)
>

Don't get me started on that subject...kaboom!   [That one's for Frank
Harrell]  :)

Dennis

>
> --- On Fri, 9/10/10, Dennis Murphy <djmuser@gmail.com> wrote:
>
> > From: Dennis Murphy <djmuser@gmail.com>
> > Subject: Re: [R] adding labels above bars in a barplot
> > To: "Antonio Olinto" <aolinto_r@bignet.com.br>
> > Cc: "R-help" <R-help@stat.math.ethz.ch>
> > Received: Friday, September 10, 2010, 2:31 PM
> > Hi:
> >
> > To add to Greg's sound advice, if you want to put the
> > numbers on top of the
> > bars, why bother with the numerical scale? The entire point
> > of a scale is to
> > provide a reference for comparing different (sets of)
> > values.
> >
> > \begin{rant}
> > And when I see things like this:
> > > dat.bar
> > >              VAR1
> > > Category 01 17.5
> > > Category 02 15.2
> > > Category 03 10.3
> > > Category 04  8.4
> > > Category 05 20.3
> >
> > I get doubly annoyed, because it is yet another attempt to
> > use a bar chart
> > to plot quantitative values by factor level. As I mentioned
> > in a private
> > response today, one of the problems with a bar chart is
> > that it forces the
> > numerical scale to have origin zero, and this is often
> > neither necessary nor
> > desirable. A simple line plot that connects the
> > quantitative values between
> > categories is sufficient, and takes *far* less ink to
> > produce. The purpose
> > of a statistical graphic is to convey information in a
> > simple, clean,
> > concise fashion - it is not meant to be a rococo art form.
> > If you intend to
> > write a function to automate a graphic, please think
> > carefully about what is
> > meant to be conveyed and the *visually* simplest means by
> > which to convey
> > it.
> > \end{rant}
> >
> > The purpose of a bar chart is to visualize a (joint)
> > discrete distribution.
> > There are better ways to plot quantitative variables by
> > group; in addition
> > to the line plot mentioned above, the Cleveland dot chart
> > can be very
> > effective with many groups or multiple grouping factors.
> > With two factors
> > and a quantitative response, another option is the
> > interaction plot.
> >
> > If this weren't the third such example/request I've seen
> > today, I probably
> > wouldn't be so apoplectic...
> >
> > Dennis
> >
> > On Fri, Sep 10, 2010 at 10:44 AM, Greg Snow <Greg.Snow@imail.org>
> > wrote:
> >
> > > See this message and the replies to it (and the
> > replies to the replies,
> > > etc.):
> > >
> > > http://tolstoy.newcastle.edu.au/R/e2/help/07/08/22858.html
> > >
> > > In there is a discussion of why you don't really want
> > to do that along with
> > > better alternatives and examples of the improved
> > plots.
> > >
> > > --
> > > Gregory (Greg) L. Snow Ph.D.
> > > Statistical Data Center
> > > Intermountain Healthcare
> > > greg.snow@imail.org
> > > 801.408.8111
> > >
> > >
> > > > -----Original Message-----
> > > > From: r-help-bounces@r-project.org
> > [mailto:r-help-bounces@r-
> > > > project.org] On Behalf Of Antonio Olinto
> > > > Sent: Friday, September 10, 2010 8:59 AM
> > > > To: R-help
> > > > Subject: [R] adding labels above bars in a
> > barplot
> > > >
> > > > Hello,
> > > >
> > > > I want to make a general routine to draw barplots
> > with numbers plotted
> > > > above each bar. See the example below.
> > > >
> > > > I could not place the numbers on the middle of
> > each bar because I
> > > > could not calculate the right position of each
> > x-axis tick. axTicks(1)
> > > > indicated a unitary step, but it does not seem
> > work.
> > > >
> > > > I appreciate any help or suggestions.
> > > >
> > > > Best regards,
> > > >
> > > > Antonio Olinto
> > > >
> > > > ======================
> > > >
> > > > CAT   VAR1    VAR2
> > > > Category 01   17.5    9
> > > > Category 02   15.2
> > 20
> > > > Category 03   10.3
> > 500
> > > > Category 04   8.4
> >    150
> > > > Category 05   20.3
> > 5000
> > > >
> > > > # Coping data from a spreadsheet
> > > >
> > > > dat.data <- read.delim("clipboard",header=T)
> > > >
> > > > summary(dat.data)
> > > >
> > CAT         VAR1
> >         VAR2
> > > >   Category
> > 01:1   Min.   :
> > 8.40   Min.   :   9
> > > >   Category
> > 02:1   1st Qu.:10.30   1st
> > Qu.:  20
> > > >   Category
> > 03:1   Median :15.20   Median
> > : 150
> > > >   Category
> > 04:1   Mean   :14.34   Mean   :1136
> > > >   Category
> > 05:1   3rd Qu.:17.50   3rd
> > Qu.: 500
> > > >
> >
> >    Max.   :20.30   Max.   :5000
> > > >
> > > > dat.bar <- data.frame(dat.data[,c(2)])
> > > > row.names(dat.bar)<-dat.data[,1]
> > > > names(dat.bar)<-c("VAR1")
> > > > dat.bar
> > > >
> > VAR1
> > > > Category 01 17.5
> > > > Category 02 15.2
> > > > Category 03 10.3
> > > > Category 04  8.4
> > > > Category 05 20.3
> > > >
> > > > par(mar=c(12,6,3,2),cex.axis=1.2,cex.lab=1.4)
> > > >
> > barplot(t(as.matrix(dat.bar)),ylim=c(0,max(dat.data[,2]*1.1)),las=2,yla
> > > > b="Y
> > > > label text",col="orange")
> > > > box()
> > > >
> > > > up <- max(dat.data$VAR1)*0.1
> > > >
> > > > for (i in c(0:nrow(dat.data))) {
> > > >
> > legend(0.25+i,dat.bar[1+i,1]+up,dat.data[i+1,3],col="blue",bty="n")
> > > > }
> > > >
> > > >
> > > >
> > ----------------------------------------------------------------
> > > > Webmail - iBCMG Internet
> > > > http://www.ibcmg.com.br
> > > >
> > > > ______________________________________________
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> > > > guide.html
> > > > and provide commented, minimal, self-contained,
> > reproducible code.
> > >
> > > ______________________________________________
> > > R-help@r-project.org
> > mailing list
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> > > and provide commented, minimal, self-contained,
> > reproducible code.
> > >
> >
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> >
> > ______________________________________________
> > 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.
> >
>
>
>

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