Good observation! "In real life" was not a good phrasing. In fact, I'm not
sure whether there is a good way to phrase it. In other words, "level of
importance" will be closely tied to sensibly choosing how much to vary each
X, and that may cast doubt on the meaningfullness of the entire concept.
PS, There is a similar example in Box, Hunter, Hunter.
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Emil M Friedman, PhD
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----- Original Message -----
From: "R. Allan Reese" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, May 08, 2003 9:45 AM
Subject: Re: Input variables
> On Thu, 8 May 2003, Emil M Friedman wrote:
> > It make perfect sense IF the scale of the X's is representative of how
much
> > they vary in "real life".
>
> Except for Sod's law. One paper I have quoted for the past twenty years
> is "Six statistical tales" by W.G.Hunter in The Statistician (V30 No 2,
> June 1981). The first tale described a new PhD given data to analyse on
> the performance of a chemical plant.....He said, "And of course, the least
important variable is
> the amount of water present." The audience burst into laughter.
..........
> R. Allan Reese Email: [log in to unmask]
> Associate Manager GRI Direct voice: +44 1482 466845
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