[R] An example of the boxplot thickness problem

[Deepayan Sarkar]

On 11/12/08, Kenneth Roy Cabrera Torres <krcabrer at une.net.co> wrote:
> Dr. Sarkar:
>
>  Thank you very much for your help!
>
>  Is there any problem that it shows this warning message?
>
>  Warning messages:
>  1:  In levels.fos - blist.height/2:
>     Length of object is greater or is not multiple
>     of the length of the shortest.
>  2:  In levels.fos - blist.height/2:
>     Length of object is greater or is not multiple
>     of the length of the shortest.

That's because the second panel has only two unique y-values, but is
given three 'box.width' values. Since the third value is NA, this
shouldn't cause any problems.

-Deepayan

>  El mar, 11-11-2008 a las 21:21 -0800, Deepayan Sarkar escribió:
>
> > On 11/11/08, Kenneth Roy Cabrera Torres <krcabrer at une.net.co> wrote:
>  > > Hi R users:
>  > >
>  > >  I reproduce the problem that I have with the
>  > >  boxplot thickness:
>  > >  ------------------------------------------------------------------
>  > >  # A data frame:
>  > >  set.seed(123)
>  > >  cont1<-c(rnorm(10,1),rnorm(5,3),rnorm(12,5),rnorm(14,3),rnorm(4,5))
>  > >  categ1<-factor(c(rep("A",10+5+12),rep("B",14+4)))
>  > >  categ2<-c(rep("Z",10),rep("Y",5),rep("X",12),rep("Y",14),rep("X",4))
>  > >
>  > >  data1<-data.frame(cont1,categ1,categ2)
>  > >
>  > >  # This is the variable that I want that each boxplot
>  > >  # be thickness proportional. (could be any other, the only
>  > >  # condition is that I have a number (or NA) for each combination of the
>  > >  # two categorical variables).
>  > >  cont2<-tapply(cont1,list(categ1,categ2),length)/length(cont1)
>  > >
>  > >  require(lattice)
>  > >  # This is the standard boxplot
>  > >  bwplot(categ2~cont1|categ1,data=data1)
>  > >  # I try:
>  > >  bwplot(categ2~cont1|categ1,box.ratio=cont2,data=data1)
>  > >  # This one also
>  > >  bwplot(categ2~cont1|categ1,box.ratio=t(cont2),data=data1)
>  > >  ----------------------------------------------------------------
>  > >
>  > >  Problems:
>  > >  1. I expect that the boxplot for the B and Y combination
>  > >    would be the most thick, and in second place the A and X
>  > >    and the last the X and B combination.
>  >
>  > I think you want something like
>  >
>  > bwplot(categ2 ~ cont1 | categ1, data=data1,
>  >        panel = function(..., box.width) {
>  >            panel.bwplot(...,
>  >                         box.width = as.numeric(cont2[packet.number(), ]))
>  >        })
>  >
>  > >  2. Why the other lines in the box of the boxplot?
>  >
>  > You are providing 6 width values for 3 boxes in each panel; the values
>  > are being recycled and each box is being drawn twice, with different
>  > widths.
>  >
>  > -Deepayan
>
>