I have done this in R and this is the following ANOVA table I get:
> summary(aov(response ~ group, data=TDat))
Df Sum Sq Mean Sq F value Pr(>F)
group 1 11203.5 11203.5 2505.0 < 2.2e-16 ***
Residuals 198 885.5 4.5
The model is response(i,j)= group(i)+ error(i,j),
we assume that group~N(0,P^2) and error~N(0,sigma^2)
I know that sigma^2 is equal to 4.5, how do I find out P^2?
In the problem that I am trying to apply this to, I have more than 2 groups.
I was hoping there would be a function that helps you do this that I don't
know about.
Thanks for your help Emma
Mark Difford wrote:
>
> Hi Emma,
>
>>>
>
> R gives you the tools to work this out.
>
> ## Example
> set.seed(7)
> TDat <- data.frame(response = c(rnorm(100, 5, 2), rnorm(100, 20, 2)))
> TDat$group <- gl(2, 100, labels=c("A","B"))
> with(TDat, boxplot(split(response, group)))
> summary(aov(response ~ group, data=TDat))
>
> Regards, Mark.
>
>
> emj83 wrote:
>>
>> can anyone advise me please?
>>
>>
>> emj83 wrote:
>>>
>>> I have done some ANOVA tables for some data that I have, from this I can
>>> read the within-group variance. can anyone tell me how i may find out
>>> the between-group variance?
>>>
>>> Thanks Emma
>>>
>>
>>
>
>
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