[AccessD] bust out the math books

On 25 Jan 2006 at 11:13, Stuart McLachlan wrote:

> The larger a number, the more weight it needs to carry in the "averaging" A
> clearer example to show why you can't just average averages to get an
> overall average.
> 

OK, bad example. That's not exactly what you were doing.
Here's a more relevant one:

1/100 = .01
9999/10000 = .9999

Weighted average:
10000/10100 = .9909

Average(?) average:
(.01 + .9999)/2 = .50495

The 9999/10000 cases clearly needs to carry 100 time more "weight" that the 
1/100 cases.





-- 
Stuart