Date:         Fri, 4 Sep 2009 10:19:58 -0400
Reply-To:     Peter Flom <peterflomconsulting@mindspring.com>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Peter Flom <peterflomconsulting@MINDSPRING.COM>
Subject:      Re: Standard deviation comparison from different samples
Comments: To: Robin R High <rhigh@UNMC.EDU>
Content-Type: text/plain; charset=UTF-8

Robin R High <rhigh@UNMC.EDU> wrote
>
>One of my all-time favorite statistical quotes deals with an analogous
>subject:
>
> "To make a preliminary test on variances [or standard deviations] is
>rather
>   like putting to sea in a row boat to find out whether conditions are
>   sufficiently calm for an ocean liner to leave port!"
>    – [George Box, "Non-normality and testson variances", 1953, Biometrika
>40, pp. 318-335, see page 333)]

Another good one, also apropos, and, I believe, also from Box:

An approximate solution to the right problem is much better than an exact solution to the wrong problem.



Of course, here, we can put your Box quote together with my Box quote to further show why boxplots are useful here:

It's a question of the exact solution to the right problem, vs. an approximate solution to the wrong problem!


Peter

Peter L. Flom, PhD
Statistical Consultant
www DOT peterflomconsulting DOT com
I write some at:http://www.associatedcontent.com/user/582880/peter_flom.html
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