[R] contingency table, several variables from dataframe

[Eik Vettorazzi]

First of all your construction of ABC leads to a structure with 3 factor 
variables due to the way cbind processes the input variables -  which is 
not intended I think.

You can do sth like

ABC<-data.frame(A,B,C)
aggregate(ABC[,2:3],by=list(A),sum)

hth.

Birgitle schrieb:
> Hello R-Users!
>
> I need a little help to build up a contingency table out of several
> variables.
>
>   A<-c("F","M","M","F","F","F","F","M","F","M","F","F")
>   B<-c(0,0,0,0,0,0,1,1,1,1,0,1)
>   C<-c(0,1,1,1,1,1,1,1,1,0,0,0)
>
>   ABC<-as.data.frame(cbind(A,B,C))
>
>   ABC
>
>    A B C
> 1  F 0 0
> 2  M 0 1
> 3  M 0 1
> 4  F 0 1
> 5  F 0 1
> 6  F 0 1
> 7  F 1 1
> 8  M 1 1
> 9  F 1 1
> 10 M 1 0
> 11 F 0 0
> 12 F 1 0
>
> I would like to count in each variable B and C the frequencies for M and F
> (variable A) and finally get the following table:
>
>      B   C
> F   3   5
>
> M  2   3
>
> Is there a function that can do that in one step?
> Tried ?structable, ?ftable, ?xtabs, ?table but could not get what I would
> like to have.
>
> Maybe I did not use the tried functions in the right way.
>
> Many thanks in advance for any help.
>
> B.
>
>
>
> -----
> The art of living is more like wrestling than dancing.
> (Marcus Aurelius)
>   

-- 
Eik Vettorazzi
Institut für Medizinische Biometrie und Epidemiologie
Universitätsklinikum Hamburg-Eppendorf

Martinistr. 52
20246 Hamburg

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