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Re: st: Average of Sample vesus Sub-Samples

From   Jeph Herrin <>
Subject   Re: st: Average of Sample vesus Sub-Samples
Date   Fri, 19 Mar 2010 09:49:54 -0400

Yes, if they are negative.

 A = -1,-1,-1
 B = -3
 mean(A) = -1
 mean(B) = -3
 (mean(A)+mean(B))/2 = -2
 mean(A+B)= -6/4 = -1.5

-1.5 > -2

So the average of all 4 numbers is larger than
the average of the means of the two subsamples.


Erasmo Giambona wrote:
Dear Statalisters,

Is it possible that the arithmetic average of a sample is larger than
the averages of two sub-samples containing overall all the
observations of the full samples?

Any thoughts would be appreciated,

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