Introduction to the normal distribution | Probability and Statistics | Khan Academy

Exploring the normal distribution

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17 replies
  1. Xirong J.
    Xirong J. says:

    Thanks for posting this Khan! However, the video is so hard to follow as there are way too many unnecessary filler info. You can probably explain everything in less than 10 min. I was thinking the entire time " waiting, waiting, waiting, still waiting…! please just explain how the function came about and how to take an integral of the function, and how did the shortcut formula involving the z-table come about."

  2. Rakesh K
    Rakesh K says:

    We are making use of Cumulative Distribution Function so that we don't have to evaluate the integral of p(x), but how are we finding CDF? Isn't that the same integral with limits changed?

  3. iamtheprogram
    iamtheprogram says:

    I find it very effective that you repeat the same ideas over and over again! It reinforces them.

  4. yoxter 3423
    yoxter 3423 says:

    great explanation, is always interesting try to see where the math formulas come from

  5. adnan hossain
    adnan hossain says:

    i dropped out of engineering and joined business school just so i dont ever have to see that GOD DAMN INTEGRATION SIGN… but… we meet again. my old foe!

  6. debendra gurung
    debendra gurung says:

    I have been here a 100 times but still find myself alienated.
    I went all the way to find what gaussian function is, and finally come back to find it is actually e^-(sqrt x) and not e^-square x, that I should look for.
    Also, Does P(x) here means (mean + sigma.x)……

  7. Farouk Bach
    Farouk Bach says:

    there is a small fault when you wrote down the fonction to integrate where the mean is -5 and the standard deviation is 10 you wrote ((x+5)/100)^2 the right expression would be ((x+5)/10)^2 or (x+5)^2/100) otherwise you have (x+5)^2/(the standard deviation)^4

  8. Zhehao Zhou
    Zhehao Zhou says:

    He could have explained this in ten minutes but he extended to 26 min, wasting a lot of time on explain some useless personal thought instead of steady proof

  9. Tiffany K
    Tiffany K says:

    Hello! I was wondering what the y axes would be labelled on the normal distribution graphs. I understand the x axes would be the number of standard deviations, but i dont know what the y axis would be

  10. The_White_Lotus
    The_White_Lotus says:

    The video was very good but please try to talk in a more coherent manner. It makes it hard to follow when you switch between concepts every 10 seconds.

  11. Jonny
    Jonny says:

    I find these videos really helpful. Got a statistics exam tomorrow, been revising off these for the past few weeks. This video is not very good though. Really confusing. 

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