Sample variance | Descriptive statistics | Probability and Statistics | Khan Academy

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Thinking about how we can estimate the variance of a population by looking at the data in a sample.
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Probability and statistics on Khan Academy: We dare you to go through a day in which you never consider or use probability. Did you check the weather forecast? Busted! Did you decide to go through the drive through lane vs walk in? Busted again! We are constantly creating hypotheses, making predictions, testing, and analyzing. Our lives are full of probabilities! Statistics is related to probability because much of the data we use when determining probable outcomes comes from our understanding of statistics. In these tutorials, we will cover a range of topics, some which include: independent events, dependent probability, combinatorics, hypothesis testing, descriptive statistics, random variables, probability distributions, regression, and inferential statistics. So buckle up and hop on for a wild ride. We bet you're going to be challenged AND love it!
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[@superfreiheit1]

This courses explain statistics better than a college course

[@Broken14647]

The tv was drawn so beautifully

[@gregharold101]

Sal, i begin studying for my MBA spring '13 at The George Washington U. My first class is a statistics based managerial class. I have no doubt that these videos are providing me a compararative advantage over my classmates

[@DeepSukhwani]

How do you do everything? I mean... You are literally an ocean of knowledge, Super amazing. Hats off to you..

[@TooWongCool]

@0:56 Sal makes a perfectly round dotted line. I couldn't get over how well it came out.

[@AaronEmbry]

Thanks, Sal. You are helping me avert terminal boredom, and meanwhile, I'm learning how to avert it's recurrence myself!

[@gaylelim6672]

thank you for posting this video, my course's slides just give us that formula at the end without fully explaining how they came about. At least by breaking it down I understand the basic steps of the formula

[@MumblingMickey]

You'r an excellant tutor btw.. There was a day, in the 70's when if you wanted to calculate any of this stuff then you had to write the entire calculation as a function in code. Often times you'd run out of memory by the time you tried to apply any of it, but these days even php has a built in stats_varience() function. One of the main reasons my math went to hell was the rise in ready made functions in computer programming languages. It removes you from the mechanics of the problem too much.

[@opufy]

Clear, crisp and concise.

[@Brownkevin7]

How is this sample variance. Isnt this population variance? The formula for sample variance involves dividing by n-1. I even double check on calculator and squared my population variance

[@muhammadabdullahi4894]

this is so helpful. really appreciate the help

[@h.a7688]

thanks i got it now much appreciated ❤🎉🎉

[@igorthompson7449]

Wow did you draw the tv

[@steven_king]

Saving my life in ECON 120A

[@parzrelmuzik]

Wonderfully clear explanation. Thank you

[@dalaladel]

Hi Sal, thank you so much about everything you have done, it is very helpful. May i ask you, what program you use to record lessons? it is very neat. Wish you all the best always. (best teacher ever)

[@beyazbulut961]

Thank you for this interesting lesson

[@kageemo]

10min of your video is better then 3h of my lecture

[@rohitlabhe850]

awesome explanation

[@billpakwaan7918]

Nice Tv!

[@joyprokash4013]

Thank you.

[@ashutoshpoudel5227]

whay are there 2 videos for the same topic !!!

[@kittyruler10]

Good eggs khan

[@blackmancer]

why can't i view any Khan video's from the last week including this one? just black video, no loading etc.

[@amansingh-ll6rc]

Why it is better to divide a number less than total? Ans mathematical reason for that????

[@h8charvs]

Stats exam in January anyone? :(

[@macfly_5164]

Yes lol even tho I’m late

[@billpakwaan7918]

2nd

[@AlanMorales502]

The United States looks like a potato.

[@TheJoseph0123456789]

Isn't this Inferential statistics? The title should be changed.