If I'm understanding the question, it's a fairness issue. :-)

The denominator (MSWithin) is the pooled variances of samples. The numerator, 
OTOH, is a variance of sample means. In essence, then, the numerator is looking 
at a sampling distribution of means. Because the sampling distribution of the 
mean has a variance of (sort of) s2/n, multiplying by n turns it into s2, which 
gives you an F (ratio of variances).

Hugh

On Feb 22, 2012, at 8:57 AM, Marc Carter wrote:

> Hi, all --
> 
> I fear this to be a really stupid question, but...
> 
> In ANOVA, why are the squared deviations in the SS between groups scaled 
> (multiplied) by _n_?  I was once told it was to weight them, but that somehow 
> doesn't seem right.
> 
> Can someone help?
> 
> TIA,
> 
> marc
> 
> The information contained in this e-mail and any attachments thereto 
> ("e-mail") is sent by Baker University ("BU") and is intended to be 
> confidential and for the use of only the individual or entity named above. 
> The information may be protected by federal and state privacy and disclosures 
> acts or other legal rules. If the reader of this message is not the intended 
> recipient, you are notified that retention, dissemination, distribution or 
> copying of this e-mail is strictly prohibited. If you have received this 
> e-mail in error please immediately notify Baker University by email reply and 
> immediately and permanently delete this e-mail message and any attachments 
> thereto. Thank you.
> 
> ---
> You are currently subscribed to tips as: [email protected].
> To unsubscribe click here: 
> http://fsulist.frostburg.edu/u?id=13238.0e762b65028402721e10bbc97ede52b7&n=T&l=tips&o=16204
> or send a blank email to 
> leave-16204-13238.0e762b65028402721e10bbc97ede5...@fsulist.frostburg.edu
> 



---
You are currently subscribed to tips as: [email protected].
To unsubscribe click here: 
http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=16207
or send a blank email to 
leave-16207-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu

Reply via email to