# Standard Deviation

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babyface11691: i finally got it. you made it so simple. i worked out the problem and got it right. thanks a million.mustashride: That was helpful, thank you.Ann Vo: Thank you so much!!! My chem teacher never explained how to use this formula in class!Adrian Galvan: i got 3.12ðŸ˜…Madissen Taylor: This was really helpful and very comfortingKowthar Hassan: Would it not be better to just sum up all residues ignoring the minus sign which only indicates direction and not magnitude. We then divide this figure by n or n-1. This should be our SD representing the average distance of each value from the mean on its right or its left. Would this not be more correct instead of squaring and root squaring? Kowthar Hassan: I have many queries about this. First of all what does standard deviation literally mean. You will say degree of spread from the mean. If so then what are 1 SD and 2 SD? Sencondly, if it the average distance of variables from the mean then why do we divide the sum by squre root of n-1 and not n-1 itself? Thirdly, instead of summing the squares of the residuals to avoid the minus sign, why donâ€™t we just the positive ones and divide by n-1/2? Kowthar Hassan: I donâ€™t understand why we include n-1 or n in the square root. I mean should we not first get the square root of the sum of squared residuals and then divide by n-1 or n.Plz explain. Thx gevxgu250: Why divided by (n-1) but not divided by n?Dlo MO: thankstoomuchsauce: Thanks for keeping the video short and simple .jrowenm: Thank you for this explanation. I am currently taking a STAT course online and appreciate the walk through of this theory (something that is missing from an online course).Basil Thomas: You're definitely going to heaven!vampire soos: thank you that helped so muchMubarak Muhammad Dangaladima: waw that is very very clear for me i gate more understand than before, thanks you very muchsmit shah: I wanted to understand the concept why in formula there is square of deviation..... If we don't square and do directly root.... So my question is why we do square....?Sophia DiPaola: thanks mr. andersen, my professor has a wicked korean accent and i had to go home and run to you for help lol thanks again!Zeppelin Travel: you didn't say how to calculate the SD in the first half of the video, and you didn't say what the SD showed in the second.mahsa mahtab: thank you so much.Pottz1616: Excellent video! |

Standard Deviation
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