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Old 07-23-2008, 09:16 AM
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Quote:
Originally Posted by Zephyr View Post
Say, Southern Man, why don't you define normal for us?
As y’all have repeatedly avoided my direct question I’ll have to answer it for you.

Quote:
Expressed simply as s.d. [standard deviation], the standard deviation is often used to show how far any one member is away from the mean. For a normal distribution, 68.27~% of members lie within 1 s.d. of the mean, 95.45~% within 2 s.d., and 99.73~% within 3 s.d. For a set of laboratory values for a repeated experiment aimed at establishing some value, the standard deviation gives a measure of the consistency of the experiments. Along with the mean to represent the targeted value, the standard deviation is often cited, usually in brackets as an integer to be applied at the last decimal place expressed for the mean, as the 1 standard deviation uncertainty.



Investopedia Says:
A volatile stock would have a high standard deviation. In mutual funds, the standard deviation tells us how much the return on the fund is deviating from the expected normal returns.
standard deviation: Definition and Much More from Answers.com

The term “normal” therefore has a measure of objectivity to it, even among statisticians. Most would agree, however, that “normal” lies somewhere between 1 and 2 standard deviations (68 to 95%), or that “abnormal” is between 5 and 32%.
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