Why Dividing By N Underestimates the Variance

This is the follow up video to:
Statistics Fundamentals: The Mean, Variance and Standard Deviation
   • Calculating the Mean, Variance and St...  

In it, we show exactly why, when we estimate the variance, dividing by 'n' underestimates the value we are interested in. It also describes why we square each term instead of taking the absolute value. The visuals used in this StatQuest make it easy to remember why we should divide by n-1, and this will save us from falling into a very common pitfall.

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Corrections:
3:23 I should have said "To understand why dividing by n underestimates the variation around the population mean".
3:40 The estimated mean was switched with the population mean.

#statquest #variance