Statistics: Standard deviation | Descriptive statistics | Probability and Statistics | Khan Academy

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  • Опубликовано: 22 авг 2024
  • Review of what we've learned. Introduction to the standard deviation.
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Комментарии • 489

  • @LadyGagaSweetBaby
    @LadyGagaSweetBaby 7 лет назад +333

    This channel provides useful and clearly explained info 100% for FREE. These people are literally investing their time and best efforts to create good content, yet people still find "what is wrong" and complain about it instead of appreciating the beauty of education available to everyone

    • @ubaidshah1910
      @ubaidshah1910 7 лет назад +4

      LadyGagaSweetBaby not education, this to me is simply information to pass an exam, then never use it again. But of course im very grateful that mr khan did this for us

    • @vaibhavmaloo7909
      @vaibhavmaloo7909 3 года назад

      Donate to them

    • @bakhodirjonkakhkharov344
      @bakhodirjonkakhkharov344 3 года назад +1

      Yeah, it the best educational channel on RUclips. We should appreciate their hard work.

    • @lemonlime07
      @lemonlime07 Год назад

      @@ubaidshah1910 because you won't go into a field that uses this concept millions of people still have to do this everyday as part of their job its used in real life

  • @JebusChrust
    @JebusChrust 9 лет назад +695

    About two hours into this program and I've already better learned statistics than a semester of the class.

    • @botlenyanasebata343
      @botlenyanasebata343 7 лет назад +4

      me too!!!

    • @maxreaper25
      @maxreaper25 5 лет назад +6

      If you can get your hands on a school curriculum you can learn better for free at home than you would at a college

    • @carzy9966
      @carzy9966 5 лет назад +7

      Hayden Dias don’t hate lol, you’re probs the dumbest kid in your class

    • @meepgoesrawr6168
      @meepgoesrawr6168 5 лет назад +6

      @@haydendias4009 haha *you swallow*

    • @janer-kd2wk
      @janer-kd2wk 3 года назад

      Yea

  • @MudnuK
    @MudnuK 8 лет назад +198

    "[Standard deviation] gives us some measure of, on average, how far the numbers are away from the mean"
    The most important and useful part of the entire video for me.

    • @saadnadeem2660
      @saadnadeem2660 4 года назад

      Sorry, I'm a little bit confused but isn't that supposed to be the Interquartile range?

    • @beingmybestversion
      @beingmybestversion 3 года назад

      Thanks

    • @SeoFam01
      @SeoFam01 2 года назад +1

      exactly, this is actually the main thing i was looking for

  • @RebeccaUzoh
    @RebeccaUzoh 8 лет назад +41

    Thank you for this very simple explanation; Biostatistics is my most challenging course this semester. Khan Academy is God's gift to students. ^_^

    • @normadicn5700
      @normadicn5700 4 года назад

      Biko ehh and for free

    • @ozzy2991
      @ozzy2991 Год назад

      I am taking statistics, now 12 years removed from high school and boy am I thankful for this video lol

  • @Ayeshachaudhary
    @Ayeshachaudhary 10 лет назад +26

    The best instructor!

  • @pablogribling8265
    @pablogribling8265 4 года назад +12

    "[Standard deviation] gives us some measure of, on average, how far the numbers are away from the mean" But in the world would you not just calculate exactly how far the numbers are away from the mean?

    • @sleepymarauder4178
      @sleepymarauder4178 4 года назад +5

      True but the thing is, sometimes it is not possible to do it for a whole population. Furthermore it is hard to say in one metric how much every point is how far away. That's why the standard deviation is a thing. It is an expression that says for this sample / population the spreadout is this.

  • @codekiln
    @codekiln 14 лет назад +7

    Kahn - thank you! My favorite morning ritual for the last couple months has been eating steel-cut oatmeal, drinking coffee, and watching one of your videos. It wakes the brain up in a painless, entertaining way. I'm a piano performance major who once considered being a math major, but never went beyond Calc 3. Having your videos makes me feel like I'm just connected enough to that world I love!

    • @Spring6101
      @Spring6101 9 месяцев назад

      Yo 13 years sense you wrote this how’s life now this comment is old and that’s crazy 1 year ago it came out when you’ll posted this comment it it’s been 14 years time flies also how is life now ya a adult now we’ll have a good day?

  • @mitkomilev4690
    @mitkomilev4690 9 лет назад +21

    Thank you a lot Sal! You secured my exam again! :)

  • @inigoelias5690
    @inigoelias5690 2 года назад +3

    13 years and it keeps usefully!

  • @adikohli4384
    @adikohli4384 7 лет назад +628

    Who is here because tommorrw is exam 🤔

  • @singhharjitgill
    @singhharjitgill 7 лет назад +8

    Hello Sir, Thank you for this video series. I have looked at other basic statistical videos around this subject, but none of those have explained to this details. Normally a 10 minutes of video also looks long as a persons ages, but your presentation style and detail coverage has bound me to the video. I am still watching the 4th video but have started to get more interested in Stats. Your very purpose of making this video series has achieved more than expected.

  • @user-wb2wl2jb5b
    @user-wb2wl2jb5b 2 года назад +2

    Realized this is a video in 2009 when I saw the Windows XP OS. Old but Gold.
    p.s. watching this series to reinforce my stat for machine learning/ data science ;))

  • @cross4324
    @cross4324 7 лет назад +40

    Shouldn't he have said Khansept? :D

  • @Sutto3721
    @Sutto3721 11 лет назад +1

    The "n-1 division" is the "degrees of freedom". The reason for this is because you are dealing with a sample. A sample represents a population but it is not a 100% accurate representation that reflects the exact form of the population. So by taking the sample's size and take away 1, we are not underestimating the true value of the population, but rather be more accurate to present our sample standard deviation to be like the population's - making unbiased results. Hope this helped. Go Khan :)

  • @nitishmuppavarapu5446
    @nitishmuppavarapu5446 6 лет назад +2

    I have to Say this Definitely, You just redefined my current way of Thinking about these Central tendencies and I am getting more and more Sense and am Reaching my Intention for Watching your videos in Particular.

  • @chezidickman
    @chezidickman 8 лет назад +7

    You are an amazing teacher. Thank you very much, i've learned a lot from you.

  •  9 лет назад +29

    Thanks a lot!!!! I wish my unversity would hire you to teach statistics....

  • @OmgItsLykeMarissa
    @OmgItsLykeMarissa 10 лет назад +85

    literally understand everything he teaches on here, rather then how my professor teaches lol

  • @aviralsingh6011
    @aviralsingh6011 6 лет назад +7

    what is the difference between variance and standard deviation as both states distance from the mean???

  • @nerdyblackgirl_x
    @nerdyblackgirl_x 4 года назад +2

    soo this video was made in 2009. its 2020 and we are still learning the same thing. wow.
    I don't know how to feeeeel.

  • @lomelabella
    @lomelabella 9 лет назад +2

    woow i m currently taking the 6 sigma certifications exam class and to tell you the truth even my teacher couldn't explain this concept as clear as u did. U good!!! thumbs up

  • @Bangalangs
    @Bangalangs 11 лет назад +3

    I learn more from your videos than I do from my college statistics class. Well done.

  • @mo6594621
    @mo6594621 3 года назад +1

    Bloody thanks much more simpler explanation than EdX course in statistics 👏🙏

  • @andrewsunderman259
    @andrewsunderman259 5 лет назад +13

    i think i might be better off just skipping my lecture and watching an hour or 2 of this every day

  • @thelife5628
    @thelife5628 Год назад +1

    14 yrs old course... STILL VERY USEFUL

  • @coxfox10
    @coxfox10 14 лет назад

    I'm a systems engineer in a 3000 level statistics class with a professor who can barely speak English. I have never taken a statistics class before so I find it rather difficult but I learn more from these videos than my prof. This guy can teach it so much better because he knows how to break it down on a beginners level. Thank you Khan!

  • @Alebtong1
    @Alebtong1 11 лет назад +2

    I am beginning to wonder why pay $6000 per semester when you can youtube anything and get a much better lesson than our overpaid professors!! i am going to start donating to Khan

  • @heyyymal
    @heyyymal 3 года назад +1

    Sal Khan is The Best Teacher from all the teachers I studied in High School❤️

  • @fruitofthepirit
    @fruitofthepirit 7 лет назад +2

    God Bless You for helping me to understand this!!

  • @ariabeatrice6217
    @ariabeatrice6217 7 лет назад

    I don't mind this type of video actually. I can still learn stuff without high resolution. Gosh people these days. Thanks for your hard work Sal. Best professor ever!

  • @scuzzy5005
    @scuzzy5005 11 лет назад +3

    Everytime I watch one of his lectures I feel not worthy. I wish I was as intelligent as him;
    I do great in school but this guy knows EVERY subject as if it is as easy as breathing! I envy him with every bone in my body!

  • @rosiecastro5322
    @rosiecastro5322 4 года назад +1

    Thanks a million!!!! This makes so much more sense than trying to understand from the book.

  • @faraway1981
    @faraway1981 11 лет назад

    I'm glad I got the best instructor ever and he makes this course so friggin easy. He has his own equations. Love it!!!

  • @kingofbad111
    @kingofbad111 14 лет назад

    You are the best, i suddenly started my Master's in computer engineering and was i bout to withdrow, after finding what this guy is teaching in math and statistics i had a hop again, u are amazing man, truly amazing by all means, keep it simple like u r doing, u made math truly to be fun.

  • @msnoah
    @msnoah 14 лет назад

    I am taking my 1st and last class in statistics.
    This instructor breaks it down and explains clearly
    I wish my professor had the same teaching techniques

  • @sandradeethmamma
    @sandradeethmamma 13 лет назад

    I just want to thank you...I have learned more from you in 13 minutes than I have learned for a week's worth of class. ;0) Thanks again!!!

  • @bontea
    @bontea 14 лет назад +3

    how do you know when to divide by the population (n) or n-1?

    • @EnsonPortela
      @EnsonPortela 6 лет назад

      Population is always divided by N.

    • @pathfinder6997
      @pathfinder6997 6 лет назад +1

      for population divide by n and for sample divide by n-1

    • @muhammedrajab2301
      @muhammedrajab2301 3 года назад +1

      Population is always divided using N and n-1 is used to divide sample. You just have to know whether the data is sample or population. If it is sample, then use n-1 and if it is population, then use N.
      Sorry for late reply :)

    • @DarkPrincess_M
      @DarkPrincess_M 2 месяца назад

      ​@@muhammedrajab2301 how am I supposed to know whether it's a sample or population?

  • @yamazakishuoh7026
    @yamazakishuoh7026 4 года назад +1

    Thank you very much for spending a precious time to make informative videos like this. I appreciate your hard work!

  • @mathhelpmadeeasy
    @mathhelpmadeeasy 2 года назад +1

    Great explanation for Finding Standard Deviation in Statistics! Thank you 🙏🏻

  • @Akotski-ys9rr
    @Akotski-ys9rr 2 года назад +1

    Out of all the times I’ve ever used khan academy, I’ve never learned anything

  • @DALLAFICATION
    @DALLAFICATION 6 лет назад +1

    So what's the difference with variance and standard deviation? I know variance is how far away below or above it is from the mean, but what about standard deviation?
    Thanks! Love the work so far, learning more than I could have imagined

  • @hotLink87
    @hotLink87 13 лет назад

    U really make it UNDERSTANDABLE.... thanks a lot i have a Test tomorrow and im not gonna fail thanks to this videos! cheers man!

  • @randomhandle09.
    @randomhandle09. Год назад

    I haven't went near math for 3+ years and needed to know this for my psych class. You saved me lol!

  • @hooliguy52
    @hooliguy52 9 лет назад +3

    Excellent video and great to review right before exams! :)

  • @vladimirrngs
    @vladimirrngs 14 лет назад +1

    thank you, Khan! with you, i understand these concepts so much better than a lot of times in my mother tongue. pls keep going. you've promised geometric and harmonic mean in the 1st video) and that's exactly what i need to brush up.

  • @michaelsharpe4217
    @michaelsharpe4217 5 лет назад +1

    I watch different math videos, and after a while I noticesDthey are all made by the same person, Sal Kahn. How does he find time to do anything else when he is making thousands of these very clear teaching videos?

  • @AhmedMohamed-ro5yl
    @AhmedMohamed-ro5yl 5 лет назад

    thank you for saving my time :) i really understand your tutorial {from Egypt}. i study computer science and it really helps me when i don'd understand from my instructor

  • @oietube
    @oietube 15 лет назад

    you are the best 1000 times better than all these professors I've had and paid so much money to, you made me GET IT all the way....I love you for that :))))))

  • @Ktangsy93
    @Ktangsy93 13 лет назад

    Take it out the word can't. Keep the word Khan. We Khan do it! keep up the good work!

  • @burntforest633
    @burntforest633 Год назад +1

    I used khan academy at gcse, and im still using him on my masters course lol

  • @joburkell
    @joburkell Год назад

    khan academy deserves the world 💓

  • @blacksilkblacksilk
    @blacksilkblacksilk 15 лет назад

    Not only that. You can rerun our friend here as often as needed. While i do have my physics degree now for over twenty years I am incredibly thankfull for this channel.
    Mr. Khan is everything I ever dreamt of when i was studying. Not to mention school.
    Merself I cannot decide if to jump out of the chair or not to leave it at all.
    Positively addictive stuff.
    have a nice day
    silk
    ;-))

  • @Seeeeaaaannn
    @Seeeeaaaannn 9 лет назад +27

    Damn I wish the image quality wasn't so shit. Great video though!

    • @djvugts5510
      @djvugts5510 8 лет назад +1

      +Seán Cahill what does it matter?!

    • @Seeeeaaaannn
      @Seeeeaaaannn 8 лет назад +2

      +Dj Vugts It would be more pleasing to look at.....?

    • @skiesatnite
      @skiesatnite 8 лет назад +2

      +Seán Cahill i think it is a good thing since image quality does nothing here. besides, the people who has slower internet can watch this too.

    • @Seeeeaaaannn
      @Seeeeaaaannn 8 лет назад +3

      I have no idea what year or third world country you're living in because there is no argument that makes 240p videos ok.

    • @Alaina7456
      @Alaina7456 7 лет назад

      u r an idiot, dumb dumb tissss

  • @jazz77ol
    @jazz77ol 13 лет назад +1

    @jazz77ol
    I just answered myself. Standard deviation is pretty much the same thing as variance Except it is the square root value of The variance. Further to calculate the variance one would uses the whole population value where the standard deviation 'requires' just the sample value.
    I thought someone else may have the same confusion and this might help.

  • @parag183
    @parag183 13 лет назад

    u saved my dream khan...thanks a lot...u r GOD to me...
    keep servicing humanity...

  • @hellokat68
    @hellokat68 11 лет назад +2

    thanks, very helpful, especially the subtitle, that helps me alot

  • @Caine61
    @Caine61 11 лет назад +2

    Khan is better... at everything

  • @alexaschannel8459
    @alexaschannel8459 9 лет назад +2

    khan academy is a lifesaver

  • @AkankshaGupta-zn7he
    @AkankshaGupta-zn7he 2 месяца назад

    2024 and here I am! The content never gets outdated!

  • @sakethlakshmanan1052
    @sakethlakshmanan1052 4 года назад

    Year 2020........still the best statistics video

  • @isa1455
    @isa1455 6 лет назад

    I really appreciate the work of this guy ! But i don't understand how he knows every subject like an expert

  • @alawimohammed6569
    @alawimohammed6569 9 лет назад +2

    God bless you. You are vey intelligent!

  • @Gspot4000
    @Gspot4000 5 лет назад

    This info is not just for passing an exam . It clearly is reaffirming what one either already knows, filling in the gap of mis understanding to better understanding or an introduction to something new for better familiarity. I get it.
    Besides if yr just doing it to pass an exam without realizing you learned something about yourself well you have missed the point for yourself and what khan academy is trying to accomplish , especially those who are visual learners more so than audio learner
    Stepping down off the soapbox now📦

  • @Ubersechs
    @Ubersechs 12 лет назад

    Hahahaha please!
    My teacher uses this guy to teach us, never the less you are awesome ;)
    With you´re help I finished a 9 page statistics essay in time. Thanks man!

  • @bakhodirjonkakhkharov344
    @bakhodirjonkakhkharov344 3 года назад

    I learned more from Khan Academy than I learned at school. So, thank you sirs

  • @JakeFishtheOcho
    @JakeFishtheOcho 12 лет назад

    i learned more from this guy in his ten minute videos then from hours of lecture from my numb-nut professors

  • @samathalev
    @samathalev 14 лет назад

    you know what your the best. I really love all your videos. Honest and they really help me a lot hope youl never stop what you are doing. Your really helping a lot of people

  • @shazaduh
    @shazaduh 15 лет назад +1

    Thanks for stat and prob videos. Please do explain or prove that why variance formula has (n-1) on the bottom?

  • @IglooGirl1
    @IglooGirl1 15 лет назад

    i NEVER thought i'd understand variance & SD...thank you soooooooooo much. I thought i was done with math 14 yrs ago but it's reared its ugly head. Thank you for making it less painful ;)

  • @Teresafarner88
    @Teresafarner88 11 лет назад +1

    n-1 is n= the numbers 1,2,3,8,7.
    you just take 1 number away to get 4 numbers instead of the original 5 numbers.

  • @CameraCalc
    @CameraCalc 11 лет назад +1

    We appreciate your help Mr. Khan. Our app calculates standard deviation just by taking a picture. You can check it out on our RUclips profile page.

  • @tathagatakar8898
    @tathagatakar8898 Год назад

    His videos still helping many of us

  • @parvinkariman205
    @parvinkariman205 9 лет назад +1

    Thank you so much. Your videos about statistics are very good

  • @brandongunnerhall
    @brandongunnerhall 11 лет назад

    Biology, physics, chemistry and maths, along with plenty other videos I haven't yet watched - What doesn't Sal Khan teach!?

  • @anandsnair2005
    @anandsnair2005 11 лет назад

    Here's a tip for my fellow students.
    1) At the bottom of this page, click 'Try something new', then switch to HTML5 player.
    2) Open up this video again.
    3) In setting, choose speed 1.5 or 2
    4) ......
    5) Profit

  • @istiakadnan1201
    @istiakadnan1201 7 месяцев назад

    things are getting interesting after watching one by one videos

  • @deen2dam
    @deen2dam 14 лет назад

    very good explanation. I feels that i shouldn't go to my statistics lectures. because i can understand those stuffs better, than in lectures. thanks. keep up your good work. Cheers.

  • @juliagerstein9771
    @juliagerstein9771 4 года назад +1

    great explanation! great voice! thank you

  • @EduardoRohdeEras
    @EduardoRohdeEras 4 года назад +1

    old, but gold.

  • @LiezhuvisSF
    @LiezhuvisSF 8 лет назад +1

    Hey amazing lessons as always, would be amazing if these videos would be upgraded to a better quality though :)

  • @MissFashionista95
    @MissFashionista95 11 лет назад

    I have the AP stats exam on Friday! What a good way to do some last minute review

  • @MegaWeirdchild
    @MegaWeirdchild 8 лет назад

    I have a question. See if the numbers 1,2,3,4 and 2,2,3,3 were each on separate tetrahedral dice and you rolled them together, which one would have the greatest probability of winning and how would you work that one? Would standard deviation be taken into account?

  • @chance20m
    @chance20m 12 лет назад

    @ion010101 That's okay, you would say those guys way out there are "x standard deviations from the mean". One of the reasons we use standard deviation in the first place is to determine whether or not a value is "unusual" or not, so a couple guys in a different galaxy don't invalidate the standard deviation at all. Think of sd as a measuring stick calibrated for a specific job. It's only as long or as short as it needs to be.

  • @alabhagavan
    @alabhagavan 11 лет назад +1

    Yes we KHAN!

  • @humzaashraf321
    @humzaashraf321 12 лет назад

    You make actually make stat. easy! Thank you!

  • @bushyboi10
    @bushyboi10 11 лет назад

    How does this guy know every subject? Amazing!

  • @pinkmusiicluva
    @pinkmusiicluva 13 лет назад +1

    This really helped me, thanks so much!

  • @divvy1400yam600
    @divvy1400yam600 13 лет назад

    Circumlocution is the major flaw in Khan's otherwise excellent presentations.
    I wish he would take steps to reduce the tedious repitition .

  • @Mikej1592
    @Mikej1592 10 лет назад

    loving this playlist, preparation for my midterm Saturday morning.

  • @user-bt2sx7sy2f
    @user-bt2sx7sy2f 5 месяцев назад

    Amazingly well explained!

  • @saudigarage
    @saudigarage 14 лет назад +1

    Thanks, I really appreciate your works. Keep it going!

  • @ChristopherBrunsdon
    @ChristopherBrunsdon 12 лет назад

    Thank you. I got an exam tomorrow and this makes it so easy to understand

  • @crustytowel
    @crustytowel 13 лет назад

    holy f**king THANK YOU. been working a real basic st dev problem for 30 mins using tha bullshit my prof gave me and it wasnt working. exam tommorrow im gonna dominate it now

  • @jeetirekhi6870
    @jeetirekhi6870 4 года назад +1

    Im in sixth and ive learnt as much as a 10th

  • @realquiller
    @realquiller 7 лет назад +2

    I love this guy.

  • @mcwinningstream
    @mcwinningstream 12 лет назад

    the contrast between the pen color and black is actually much more discernable and memorable to the visual cortex -- please don't use big words if you don't know what you're talking about!

  • @elagopaulus3017
    @elagopaulus3017 3 года назад

    YOU ARE THE BEST KHAN!!!!!!!

  • @Barnekkid
    @Barnekkid 15 лет назад

    Very good video. So is it appropriate to say the standard deviation tells the average distance for the data points from the mean?

  • @IzaakOnos
    @IzaakOnos 12 лет назад

    that makes sooo much more sense! thank you!

  • @coralia127
    @coralia127 15 лет назад

    THANK YOU SOOOO MUCH!!!!!!!!!!!!! you have NO IDEA how much this has helped!!!!!!!1