Timeline for Why Standard deviation formula has n-1 in the denominator but Variance only n?
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Nov 21, 2019 at 21:22 | comment | added | Giulia Martini | If 1,2,3 is a sample you actually do not know what is the mean value of the population. For this reason you prefer to overestimate the population variance and standard deviation using $n-1$. | |
| Nov 21, 2019 at 21:18 | comment | added | Giulia Martini | Look at the answer to this question: stats.stackexchange.com/questions/3931/…. I think it explains well what you have unclear | |
| Nov 21, 2019 at 21:11 | comment | added | luky | You mean -1 in sample and and N in the population. But if i have eg 1,2,3 POPULATION then it make sense that SD is 2/2 = 1 because 2 is mean, so SD 1 is kind of correct SD, but if i compute it like population not sample then i do 2/3 = 0.66 SD which is not so much correct. | |
| Nov 21, 2019 at 21:06 | history | answered | Giulia Martini | CC BY-SA 4.0 |