Message-ID: <20030613075738.GE10227@boromir.ci.tuwien.ac.at>
Date: 2003-06-13T07:57:38Z
From: David Meyer
Subject: formula (joint, conditional independence, etc.) - mosaicplots
In-Reply-To: <200306130111.33130.gina.joue@ucd.ie>; from gina.joue@ucd.ie on Fri, Jun 13, 2003 at 02:11:33 +0200
On 2003.06.13 02:11, g wrote:
> Hi,
>
> Can someone set me straight as to how to write formulas in R to
> indicate:
> complete independence [A][B][C]
Freq ~ A + B + C
> joint independence [AB][C]
Freq ~ A * B + C
> conditional independence [AC][BC]
Freq ~ A * C + B * C
> nway interaction [AB][AC][BC]
Freq ~ A * B * C - A:B:C
You might have a look at demo(mosaic) in package vcd.
g.,
-d
> ?
>
> For example, if I have 4 factors:
> hair colour, eye colour, age, sex
>
> does
> > mosaicplot( frequency ~ hair + eye + age + sex)
>
> mean that the model fitted is of complete independence of all factors
> [hair][eye][age][sex]?
>
> So does
> > mosaicplot(frequency ~ hair + eye)
> mean that the model is of conditional independence
> [hairAgeSex][eyeAgeSex]?
>
>
> How does the operator * as in
> > mosaicplot( frequency ~ hair * eye)
> or
> > mosaicplot( frequency ~ hair * eye + age)
> equate to in the type of independence model used?
>
>
> Thanks in advance for any elucidation!
>
> Gina
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help
>
>