Range, variance and standard deviation as measures of dispersion | Khan Academy

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[zinaalabdaly]

And here i am, 10 years after this was posted, learning more here in 12 min than my course in an hour
Thank u from the heart of mine, khan academy !

[sachimoo]

I am taking a Statistics class online and YOU are by far the BEST thing I've come across! Your explanations are clear and thorough.  You cut through all the STATISTIC jargon and allow the student to conceptualize the theory of basic statistical analyses & problems. You are truly Gifted!Thank you for sharing your knowledge and Passion.

[harijsijabs]

This made so much more sense than my university professor. Thanks a lot! 

[murators]

Please never delete your videos. I am also 10 years after posting learning this stuff and you are the only one who explained it the way i could understand and use it. Youe helped, help and will help millions of people. Thank you

[StopwatchRobert]

You know Mr. Khan, you and you alone are the reason this program works so well. What you teach is no different than a university professor, but the way you teach it squeezes more information into a 12 minute video than I'll get in a 50 minute lecture, and I understand it much better. I think I speak for everyone when I say I wish you were my teacher, you'd be absolutely perfect at it.

[fabbabs]

I have studied these concepts in at least three different classes and never understood them as well as I do now. Thank you. 

[Supremepie]

Khan academy... helped my 14 year old self, and still helping me at 24 years old, God bless you.

[BrianKouhi]

Amazing teaching skills, i've struggled to understand this in university for the past 2 months, with my prof being of little use. first time watching this 10min video and i completely understand it now! Thank you!

[nlywrld]

This guy has done so much on Khan Academy, he should be nominated for the Nobel Prize in Education. If there isn't such a category, they should create one

[kk]

Oh my god yes. Not all superheroes wear capes

[jeremyrodriguez]

Currently a history major with a minor in political science. Took statistics in high school and again in college but this just made so much sense. To anyone reading the comments, watch frequency tables first and then start looking at this video. It takes15 minutes for both but you'll appreciate so much math quickly.

[HannanAli]

If only you guys could see how the teacher teaches this subject at my university...You'd hate this subject i guarantee. She straight up reads solutions from the guide book without explaining whats happening or why we are doing anything.... Thank You So Much Khan Academy!!!

[nelsoncastillo]

Your method of teaching is comprehensible, thanks

[Lani]

Everyone is talking about their professors in university and how they're useless like 7-2 years ago I'm here in 2020 trying to figure this out in high school because I hate remote learning.

[Notabot]

Learned more with this video than the first 3 weeks of college with my useless professor

[coreyw]

You're so clear and cut through the jargon so well that it's actually making me mad. I spent so much time in college trying to understand this stuff and if I would have just watched these videos instead I can't even think about the amount of time and effort I would have saved. Great stuff

[coolshante]

There am I scrolling down and liking every comment coz I can relate to them

[saulmatakarawa]

Very well explained. However, I find another explanation stating that the denominator in variance calculation should be n-1, which in this case should be 4 (5-1=4). Please clarify. Thanks

[fangtzukang]

The most helpful explanation about standard deviation I've ever watched. Thank you so much, Sal!!!! You're the best math teacher in the universe.

[coronnation]

You have been helping me pass university classes for the last decade.
You're a very important person in the world.