[R] extracting p-values from Anova objects (from the car library)

Johan Steen johan.steen at gmail.com
Tue Aug 24 01:31:39 CEST 2010


Thanks a lot! It sure helped.
also thanks to all other repliers.

kind regards
Johan

Op 23/08/2010 23:53, John Fox schreef:
> Dear Johan,
>
>> -----Original Message-----
>> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
> On
>> Behalf Of Johan Steen
>> Sent: August-23-10 3:02 PM
>> To: r-help at r-project.org
>> Subject: [R] extracting p-values from Anova objects (from the car library)
>>
>> Dear all,
>>
>> is there anyone who can help me extracting p-values from an Anova object
>> from the car library? I can't seem to locate the p-values using
>> str(result) or str(summary(result)) in the example below
>>
>>   >  A<- factor( rep(1:2,each=3) )
>>   >  B<- factor( rep(1:3,times=2) )
>>   >  idata<- data.frame(A,B)
>>   >  fit<- lm( cbind(a1_b1,a1_b2,a1_b3,a2_b1,a2_b2,a2_b3) ~ sex,
>> data=Data.wide)
>>   >  result<- Anova(fit, type="III", test="Wilks", idata=idata,
> idesign=~A*B)
>>
>>
>> Any help would be much appreciated!
>
> I'm afraid that the answer is that the p-values aren't easily accessible.
> The print method for Anova.mlm objects just passes through the object
> invisibly as its result, as is conventional for print methods. The summary
> method does the same -- that isn't conventional, but the summary method can
> produce so many different kinds of printed output (various multivariate test
> criteria for models with and without repeated measures; for the latter,
> multivariate and univariate tests with and without corrections for
> non-sphericity) that the printed output is produced directly rather than put
> in an object with its own print method.
>
> What you can do is take a look at car:::print.Anova.mlm or
> car:::summary.Anova.mlm (probably the print method, which is simpler) to see
> how the p-values that you want are computed and write a small function to
> return them.
>
> I hope this helps,
>   John
>
> --------------------------------
> John Fox
> Senator William McMaster
>    Professor of Social Statistics
> Department of Sociology
> McMaster University
> Hamilton, Ontario, Canada
> web: socserv.mcmaster.ca/jfox
>>
>>
>> Many thanks,
>>
>> Johan
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
>
>



More information about the R-help mailing list