Sample standard deviation and bias | Probability and Statistics | Khan Academy

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[hudsonlind]

Sal has become the voice of math for a whole American generation

[designersdelight]

Thumbs up! absolutely thrilling to watch a true and great muslim doing work for humanity

[SaraphL]

Good guy Sal

makes new videos on topics we already know just so we can watch them in 720p.

[ProsaicPudding]

But how DO you find the unbiased standard deviation??

[blue]

I love math, specifically statistics! :) Thanks for making these videos to show people that math can be mastered *and* fun!

[micery]

Thank you for your help! I have midterms tomorrow!
And for fun...
2:49 seizure :)

[Kashif_Javaid]

I noticed this new trend now where Sal has done these calculation ahead of time.

[gmvsea]

my memory is fuzzy here, but i seem to remember that the expected value of the sample standard deviation approaches the population standard deviation---or is it the expected value of the sample variance approaches the population variance?---why not just use absolute values instead of squares for computing the standard deviation directly---wouldn't that avoid the non-linearity problem?---of course, i suppose since variance it's defined by squaring the differences...

[nixhj]

why was 1 taken from 8 to divide my 7?

[prettyo.]

but how do you get those starting samples? in my homework my teacher jst gave me 2 columns of 4 numbers, one for "the trucks' age" and one more for the "dollars spent on reparations of the past year" im screweddd D8

[nocturnalvisionmusic]

Awesome video and like 500 (11/28/23) 🥳💓

[ahmedemary]

what is bias?and why is Sn-1 is called unbiased?

[topgrain]

Still too much terminology that all sound the same. I get the questions wrong because of that.

[paulramones]

I know I'm not the first to ask, certainly not the last, but what program is the calculator?

[viewsfromsameer]

anyone know where to get that calculator? i really need it
thnks

[Majora]

you sound like wowcrendor... might be that it's 2 am

[Siouxjin]

Lol,
the "Math-bot" got an error of some kind

[laurellion]

Maybe I'm the dummy here, but those numbers don't add up to 48 for me.