[R] Multidimensional contingency tables

[hadley wickham]

On Mon, Apr 21, 2008 at 9:46 PM, Robert A. LaBudde <ral at lcfltd.com> wrote:
> How does one ideally handle and display multidimenstional contingency
>  tables in R v. 2.6.2?
>
>  E.g.:
>
>   > prob1<- data.frame(victim=c(rep('white',4),rep('black',4)),
>  +   perp=c(rep('white',2),rep('black',2),rep('white',2),rep('black',2)),
>  +   death=rep(c('yes','no'),4), count=c(19,132,11,52,0,9,6,97))
>   > prob1
>    victim  perp death count
>  1  white white   yes    19
>  2  white white    no   132
>  3  white black   yes    11
>  4  white black    no    52
>  5  black white   yes     0
>  6  black white    no     9
>  7  black black   yes     6
>  8  black black    no    97
>
>  The xtabs() function doesn't seem appropriate, as it has no means of
>  using 'count'.
>
>  This must be a common problem.

You can also use the reshape package (http://had.co.nz/reshape)

cast(prob1, victim ~ perp, sum, value="count")
cast(prob1, victim ~ perp ~ death, sum, value="count")
cast(prob1, death + victim ~ perp, sum, value="count")

etc.

Hadley
-- 
http://had.co.nz/