Re: A Purpose For Frt Car Distribution Studies

Anthony Thompson <thompson@...>

Gene Green wrote:
-Does- average always mean the same thing? I learned (correctly, I hope) that "average" could be one of three things; mean, median or mode. Usually when folks - those unencumbered by formal education - say "average" they actually mean "arithmetic mean."
Yes, Gene, I agree that the person in the street thinks of the arithmetic mean as the "average," and that definition is fixed, which is why I expressed doubt about the concept of a "true average." For a unimodal symmetrical distribution, the mean, median and mode lie at the same place, so for many situations you can lump them all together as the "average." But the minute the distribution is skewed, and many real-world distributions are skewed, the three definitions give different answers, and the "middle" of the distribution no longer lies at the most frequent value (the mode).

Tony Thompson Editor, Signature Press, Berkeley, CA
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