Why We Divide by N-1 in the Sample Variance (The Bessel's Correction)

Published: 23 March 2023
on channel: DataMListic
12,460
376

In this video we discuss why and when we divide by n-1 instead of n in the sample variance and the sample standard deviation formula, known in the statistics literature as the Bessel's correction. This method corrects the bias in the estimation of the population variance. but only partially corrects the bias in the estimation of the population standard deviation (and that's why I didn't include the standard deviation in this video).

References
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Expected value of sample variance proof: https://proofwiki.org/wiki/Bias_of_Sa...


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Contents
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00:00 - Intro
00:19 - Population vs Sample Statistics
01:22 - Population vs Sample Biased Variance Example
02:13 - Expected Value of the Biased Variance
03:34 - Bias Source Intuition
04:38 - Degrees of Freedom
05:55 - Outro


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#variance #standarddeviation #bias #statistics


Watch video Why We Divide by N-1 in the Sample Variance (The Bessel's Correction) online without registration, duration hours minute second in high quality. This video was added by user DataMListic 23 March 2023, don't forget to share it with your friends and acquaintances, it has been viewed on our site 12,460 once and liked it 376 people.