Math Videos - Standard Deviation

[Snowbobadger]

Thank you very much! Helped me with my GCSE Stats

[FeedmeJUice]

Um... ¬_¬ he's cute! anyways *off to take my stats exam* -_-

[TransientWriting]

thanks!

[ssips720]

dont you have to divide by n-1 ? because its only a sample...? not popuLation

can someone comment here

[agustaf4s]

Everyone else on YouTube had a difficult annoying video but this really helped thanks!!!!

[alitou001]

@agustaf4s so true

[MISSMEGGYBOOBOO]

FANTASTIC!!! A* :-)

[farnoud]

simple and quick, thanks

[MegaRumano]

thanks for the vid, great help!

[rnbdeejay]

Why wouldn't using the differences between the values 1, 2 and 6 from their mean (3) which would give 2, 1 and 3 and then adding these up to give 6 and then working out the mean from those figures giving 2 as the standard deviation be correct?

[Lekel09]

this video makes it a lot easy to understand st. dev. Thanks for taking the time to explain why u square and square root it .. and the keyword is really "taking the average of the difference from the mean".

[hazyss]

The keyword: "taking the average of the difference from the mean". Thanks million times. That helped alot!

[sohanarajaji]

awesome :) thanx

[FreeRouletteSystems]

Thanks for the detailed explanation

[UhhSplat]

thanks

[Marzerous]

thanks!



[reina123ish]

thanks for teaching this! it's so helpful! my tutor in school couldn't explain any of it, and was an impatient jerk, but i learned it with you so easily! you should become a math professor! :-)

[chupzzzzz]

your nose is retarded and you did it wrong... noob

[FxknKonviikt]

@chupzzzzz ...heh fuck u he helped me out

[ReliJon]

lmao it is N-1

[palui]

Go back to school and learn standard deviation, and when you learn it, keep it to yourself.

[SGCRCT]

this is wrong you fucker!

[danstickman1]

thanks you so much man. That has helped me so much the way that you explained it.

[EspieMoraDennis]

this is wrong. I hope nobody's test scores are depending on this video!

[jacktredgold16]

very easy to understand , coz most people use far to many technical words. thanks 

[sparco8493]

Much easier to understand than my book, thanks brah

[snowmchristv]

perfect!!!!!

[kdubbsholla]

this helped me more than my textbook!! thanks

[RoyWriter]

ugh my math teacher sucks!

i need to come to youtube to actually understand the math!

[NewYork17]

This guy is great. I finally understand Standard Deviation

[93Rhod]

When you get the root of something it can either be posotive or negative

[allptekin]

it is false. it must be square root of 7. And it is 2.645751.

[MrWazooski]

that's not really the formula... it must be a square root of the summation..etc. you must fucking do the summation first.. square root is the last... the numerator in your formula can still be simplified in a way that the square root and the square can be canceled... this is not your field, leave stats to the statisticians.

[MrWazooski]

Is that really the reason why we need to square the difference? because we don't want it to be negative?........... can we just take the absolute value of the difference for the same reason?

hmmm No for sure..haha

[swansea1jack]

it doesn't have to be -1. In my biology book it says -1 and in my math book it says just n. But we just use n

[holyorderoftruth]

@swansea1jack It does have to be n-1! For a population, the denominator is "n", but for a sample, it is "n-1". He is using the data in the context of a sample.

[icantloose]

good stuff, thanks!

[vesiu5]

Great work!!!! Thanks.

[Fluxir55]

thanks really helpful

[mosamaster]

mmm... I think the formula used is wrong.. can you repost this with the corrected formula, so that new students dont get confused...

[Dini2525]

You do the square root last.

[THErealKayneWest]

LOL this is wrong man, what infinite said is right, u have to first DIVIDE BY N, then take the SQUARE ROOT.

:D

[prismflash]

hahaahah i wonder how many people flunked from listening to the guy on the video LOL

[pink408209]

So much better then my professor he just threw sigma notation on the board and moved on

[Excitotoxin]

Great explanation (5 stars), but wrong formula. Should be √∑|xa-x0|²÷n-1 like others have pointed out. This is because you don't have a large enough number of samples in this example to use the "mean deviation."

[alinhabiolog]

That was really good!! thanks

[prsilah]

Thanks for this video, I see where I went wrong on my lab report.

[theonlyyadgirl]

Great. Thank you.

[TeleriAnne]

Man you helped me better than my lecturer Thanks ^^

[3102375]

good and learning

[sdot15]

YOU SAVED MY ACADEMIC LIFE!!!

[infinitelove88l]

No. the formula states that whatever your sums are you would divide it with n-1...which is the population - 1....

[infinitelove88l]

No, the answer is wrong. You have to divide your total by n-1, which is 2. Therefore, 15/2=7.5. Square root of 7.5 is 2.738612788.

[spencergha]

isn't he right, if he were calculating standard deviation from the population rather than the sample - in your case

[800154870]

thnx man, i forgot how to calculate standard

 deviation ,now i know.

[atlroc99]

hhahah...WTF

[G1smurfen]

You know back in the days of Socrates you would probably be forced to drink poison for such false teaching!;)

[G1smurfen]

if you want to write it in exel:

=sqrt((((1-3)^2+(2-1)^2+(6-3)^­2)/(3-1)))

= 2,645751 and then you got your standard deviation...

or you can simply type in your observations and use the stdev funktion in exel

[G1smurfen]

ha ha ha... lol... this method is wrong.. the square root is used in the wrong place.

the real answer is 2.645751 just to be accurate.

[guillesolano8]

You showed me how to do Sd a lot quicker man, thank you. I have an exam tomorrow on SD and Spearmans's rank correlation coefficient. :s

[doaqiskool]

thx bro

[LilMissae]

Thanks from Australia xD

[dongquixotee]

im in second year. thanks. you helped a lot. :p

marc, philippines

[KyleBoy0892]

Thanks, my stat teacher doenst explain it this well!!

[Kingdolo]

Thank you very much from Lafayette LA

[ifyouwerefood]

thanks so much for such a clear explanation!

[xxAmylicious13xx]

U help me a Lot! Thanks Amy Puerto Rico