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Message #2994 of 4072 |

Re: [Statisticians_group] standard deviation

Hi Amy,

It's in the equation to help compensate for sample sizes.

For example, if your sample size is huge, subtracting 1 from N won't cause the standard deviation to be much different than simply N.

However, if your sample size is small, subtracting 1 from N will cause your standard deviation to be larger. And the smaller the sample size, the larger it will be.

Make sense?

Regards!

Scott

--- On Thu, 11/6/08, moccalatte2003 <amymoore20@...> wrote:

From: moccalatte2003 <amymoore20@...>
Subject: [Statisticians_group] standard deviation
To: Statisticians_group@...
Date: Thursday, November 6, 2008, 8:11 AM

Hey people,

I have a question does anyone remember the logic behind the denominator
(N-1) for standard deviation? I need a simpliest terms explanation.
Thanks.

-Amy

Fri Nov 7, 2008 2:45 am

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Scott <bigmagumba@...>

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Message #2994 of 4072 |

Expand Messages	Author	Sort by Date
Hey people, I have a question does anyone remember the logic behind the denominator (N-1) for standard deviation? I need a simpliest terms explanation. Thanks....	moccalatte2003	Nov 6, 2008 1:11 pm
Thank you for all the explanantions it is clear to me now! I am brushing up on my statistics and came across that equation. I couldn't explain the denominator....	moccalatte2003	Nov 6, 2008 6:03 pm
Thank you for all the explanantions it is clear to me now! I am brushing up on my statistics and came across that equation. I couldn't explain the denominator....	moccalatte2003	Nov 6, 2008 6:03 pm
Hi Amy, Â It's in theÂ equation to help compensate forÂ sample sizes. Â For example, if your sample size is huge, subtracting 1 from N won't cause the...	Scott bigmagumba	Nov 7, 2008 2:45 am
Scott, Someone reminded me of the max likelihood estimation...its N-1 to make the equation unbiased so as to avoid underestimating the std. I understood...	moccalatte2003	Nov 7, 2008 3:30 am
Assuming N is the sample size, N-1 is only to ensure unbiasedness property of the statistic 'sample variance' for the corresponding parameter"population...	KAUSHIK BHATTACHARJEE kabonline07	Nov 7, 2008 8:02 am
[Side note: Whitehead declension: _My_ study has a large dataset, and so reaches strong conclusions. _Your_ study has a moderate dataset, with questions on the...	Jay Warner at AT_T jaywarner2008	Nov 7, 2008 5:00 pm

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