R help - Jun 2003 - formula (joint, conditional independence, etc.) - mosaicplots

Hi,

Can someone set me straight as to how to write formulas in R to indicate:
	complete independence [A][B][C]
	joint independence [AB][C]
	conditional independence [AC][BC]
	nway interaction [AB][AC][BC]
?

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

?formula

Simon Blomberg, PhD
Depression & Anxiety Consumer Research Unit
Centre for Mental Health Research
Australian National University
http://www.anu.edu.au/cmhr/
Simon.Blomberg at anu.edu.au  +61 (2) 6125 3379

> -----Original Message-----
> From: g [mailto:gina.joue at ucd.ie]
> Sent: Friday, 13 June 2003 10:12 AM
> To: r-help at stat.math.ethz.ch
> Subject: [R] formula (joint, conditional independence, etc.) -
> mosaicplots
> 
> 
> Hi,
> 
> Can someone set me straight as to how to write formulas in R 
> to indicate:
> 	complete independence [A][B][C]
> 	joint independence [AB][C]
> 	conditional independence [AC][BC]
> 	nway interaction [AB][AC][BC]
> ?
> 
> 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
>

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
> 
>