Re: Typical small roster for New England, circa 1952


Anthony Thompson <thompson@...>
 

Tim O'Connor wrote:
Sorry Prof, but the standard deviation is an OBSERVED FACT and not
a fixed mathematical notion. It is a measure of dispersion of the
data in the samples.
Sorry, Tim, the standard deviation is what you get with a PARTICULAR sample from a larger population. If you sample a larger group from that population, then you get the result I stated: because you have more data, your knowledge of the dispersion is BETTER and the std. deviation goes DOWN. Of course it is an OBSERVATION for your sample; and if you sample more extensively from the same population, you get a SMALLER OBSERVED deviation. I won't bore the rest of the list with details, but Tim, you should look it up.

It is as I stated, the Variance (the term I prefer) of the prototype is
greater than the Variance of the model. (Variance simply being the square
of the Standard Deviation.)
Variance is fine, but its relation to the std. deviation is fixed. My answer is the same if you choose the variance.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
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