How To Calculate The Standard Deviation of Grouped Data

This statistics video explains how to calculate the standard deviation of grouped data. It discusses how to calculate the mean and standard deviation given a frequency distribution table.
Statistics Formula Sheet: bit.ly/47zjTVT
Introduction to Statistics:
• Introduction to Statis...
Arithmetic, Geometric, & Harmonic Mean:
• Arithmetic Mean, Geome...
Cumulative Relative Frequency Table:
• How To Make a Cumulati...
Quartiles, Deciles, & Percentiles:
• Quartiles, Deciles, & ...
Interquartile Range & Outliers:
• How To Find The Interq...
___________________________________
Skewness & Symmetric Distribution:
• Skewness - Right, Left...
Sample Mean and Population Mean:
• Sample Mean and Popula...
Mean, Median, & Mode - Grouped Data:
• Mean, Median, and Mode...
Standard Deviation:
• How To Calculate The S...
Variance:
• How To Calculate Variance
___________________________________
Mean Absolute Deviation:
• Mean Absolute Deviatio...
Standard Deviation of Grouped Data:
• How To Calculate The S...
Introduction to Probability:
• Introduction to Probab...
Probability Formulas:
• Probability Formulas, ...
Final Exams and Video Playlists:
www.video-tuto...

[@TheOrganicChemistryTutor]

Statistics Formula Sheet: bit.ly/47zjTVT Final Exams and Video Playlists: www.video-tutor.net/ Full-Length Videos & Worksheets: www.patreon.com/MathScienceTutor/collections

[@noahkiptoo8261]

Kindly do videos on Partial Differential Equations

[@pierrejeppsson4674]

I never comment. I have probably watched 20 different videos on this topic (with and without excel), and this is by far the best one. Well done sir.

[@saltyfries3943]

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this guy's videos are the sole reason I can slack off in class lol

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Me too🤣

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[@graces_o]

Frfr

[@BigPropeller14]

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[@apayimary8916]

I was literally dodging this question in exams but now I've understood it well. Thanks allot This is worth subscribing for ❤

[@ManasiChattarajMONA]

Very helpful for beginners, i recommended your videos to my students for learning statistics using excel..All the best , keep up the good work sir..

[@josephvargas7409]

Better than my professor online class at notre dame. And it’s FREE

[@PreciousHuddle]

same for me as wel, wait you have classes at that church/museum in paris/france?

[@gunamuthu3761]

@@PreciousHuddle Its a university in indiana

[@VictorOrdu]

I did online stats classes at Notre Dame and they were super easy and understandable. I can't remember the professor's name though...

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How much is your semester fee?

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[@nikkipew]

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[@odiokaeze1963]

This will really help me for my statistics exam tomorrow.. thanks alot.

[@raymondbenny8322]

Thank you and loved watch all the videos . You explain better than my lecture.

[@graceahaiwe357]

Thanx this was really helpful and easy to understand

[@givenup2449]

Thank you my dude just saved me from my gcse

[@marshmallow1553]

Thank you, having exam today Wish me luck

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You’re my saviour

[@somethingaboutstatistics5537]

Nice presentaion. 🌹

[@christinekatongo1252]

Very helpful

[@saskiasanchez6459]

U absolute angel

[@lebomokoallo6869]

Thank you 😁

[@elizabethwambui3996]

I have now understood

[@kalo810]

a great piece of work, thanks!

[@MwanamaindaSinjabvu]

Good job sir...

[@thenicehater4552]

i come back here every year

[@cocokisses1293]

Midpoint is the lower boundary of the class plus the lower boundary of the next class /2, not the low plus the upper boundary of the class

[@Someasshole1000]

I know! this had me messed up for my quiz. I need to prepare harder to pass my test. Midpoint in our class is found differently just like you said @Kim Baker which gives a totally different answer. I'm surprised no one else has mentioned this.A good question is why there is a difference in the first place?? I have read both ways in two different stats books.

[@AethernaLuxen]

Well, it doesn't really matter Addition can be switched

[@Shin-lv1fw]

11:40 best part

[@naumaankhan7498]

Why did we use n-1 instead of n in denominator ?

[@samuelbambi3921]

Why is the (M-X)² results in the table positive and not negative?

[@jesalynmanulat9062]

Why do 90-100 has a different class width? It suppose to have the same class width

[@noorshikinaidawahab]

good info

[@nutella682]

Omg Thankyou this saved my life asdfghjkl

[@onlineshop98-e1y]

THANK YOUUU

[@davidryan787]

So, in other words, standard deviations predicts that 68% of this group of grades are expected to fall within 12.3 points of 79.2 ?? I'm clarifying for a friend : )

[@rajkecy2223]

my book does not have (n-1) in the formula of Standard deviation... It just has "n" Which formula should I use??

[@emilymurigi7137]

Thank you, your teaching is very simple and easy to understand. i am now able to calculate SD without issue. God bless

[@moikegandu7996]

Ulisikia wapi

[@conamore7887]

@@moikegandu7996 hahahaha 🤣 hapa KZbin. Nawe pia ulisikia wapi? 😀

[@crazecream241]

Thank you for teaching, you're one of my go to teachers here in youtube when it comes to math and stats. your explanations are simple and straight to the point and easy to understand!

[@surbhi1353]

Hey..!! Can You Help Me Out!! The formula of SD for Grouped Data is root over submission of {f(m-X)^2} whole divided by "n" But He has written divided by (n-1).

[@HotFiya05]

@@surbhi1353 This is late, but since it's a sample, you divide by n-1. Total population you'd divide by N

[@JimboPro]

@@surbhi1353 what

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Whoever you are bestie, I hope the best for you. You've always been there when our professors haven't. King👑.

[@bidiptaghosal9470]

Representation of Statistical Data(Textual, Tabular & Graphical) and their advantages & Disadvantages

[@tturi2]

I know it only took you twelve minutes, but this took me an hour haha

[@belindacraine296]

You rock!!!!! I asked my instructor how to answer like this and he couldn't help me AND this is his class. Thank you so much!!

[@PreciousHuddle]

damn

[@umeshtamang2322]

Tq so much sir

[@grhay3015]

thanks its a great help on me coz my prof didnt discuss this but we have activity about that

[@X.U.M_official]

why is that in statistics there are almost no videos on deriving the formulas. we are just given formulas to cram.

[@leecheechiang]

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Please klik this linl.... kzbin.info/www/bejne/omXPeJRjYsyeepY This video also about of MEAN

[@ajaychoudhary9817]

the rare math tutorial where its not some random indian guy

[@nosms6581]

Thank you sir. But I have a question why it's an n-1 in the denominator why it's not just n??

[@acholarandall7025]

I watched this a few minutes to exams it was really helpfull

[@malungo9584]

Thank you so much it has really helped me, am going to write a test today. I really appreciate.

[@AhmedMostafa-so2jp]

did u pass?

[@optics2888]

correct me if i am wrong, but in standard deviation i think we don't minus (-1) from N. formula is Fi(Xi-X bar) square / n

[@hitfromcs]

thats what my uni teacher taught too. im hella confused and got an exam in 8 hours

[@jenlee05]

was the m an X? it is? right?

[@d.m.d7600]

Yes it stands for the midpoint values

[@jenlee05]

@@d.m.d7600 thank you

[@somayamaizate9374]

I really don'y know how to thank you except for watching all the ads ! you really helped me a lot . I wish a happy life , really

[@poulvincentnamocot4252]

why there is n-1 i saw other tutorial they define the standard deviation as the square root of variation that has formula of SUm of f(m-x)^2 over Frequency

[@JP-bh6jh]

I think that the range 90-100 should be 90-99. Right? Just a little mistake i think. I tried to solve it and compared to your work. So i think that a lil mistake can really change the whole thing.

[@nelsonshaanika8692]

broooooooooo thank you very much. lecturer taught us for 110 minutes and understood nothing but just watched 12 minutes of your video and understood the whole topic

[@challenge-yt8351]

Thats long... But it helps!

[@Aiden-fm6by]

Thank you for this video! Very easy to understand, you walked through the steps very nicely, and explained things simply. I was able to complete my homework because of your video!

[@surbhi1353]

Hey..!! Can You Help Me Out!! The formula of SD for Grouped Data is root over submission of {f(m-X)^2} whole divided by "n" But He has written divided by (n-1).

[@shripadsg]

@@surbhi1353 Its for Sample not for Population!

[@ahmedamin6043]

Thank you🙏 so much I have understood

[@isaacocakacon4601]

grate, i can now show that am coming up in basic statistics

[@BobBeatski71]

Can you please explain why you have used /n-1 instead of /n because, to me, it appears you have used all the data points and not a subset of them (ie population subset).

[@TheGunzSkido]

asking same question. did you get the answer?

[@cocokisses1293]

n-1 is what you use for sample variance, n is what you use for population variance

[@TheGunzSkido]

@@cocokisses1293 thanks.

[@cc32001]

Thank you so much, I hate memorizing formulas without understanding why it works. This video helped so much!

[@Its_SRRS]

Dear Tutor, You need uniform class interval i.e. of equal size, you've taken the last interval as 90-100 i.e. wrong either it should be 90-99 so that class size remains same or you should make the discontinuous class intervals to continuous class intervals viz. 49.5-59.5, 59.5-69.5, 69.5-79.5, 79.5-89.5, 89.5-99.5 and after this you'll get correct values for M. It goes wrong at 2:26 Hope you'll correct it.

[@stefandutoit9957]

Considering that these are grades and some individuals are capable of achieving 100%, wouldn't it make more sense to include 100? (Not trying to crush your comment, I'm just trying to gain more insight)

[@Euleogy]

I noticed this too. For the ranges I would do 51-60, 61-70, etc etc. And then for your midpoint it's not 60-51, you're supposed to find the difference between the lower class limits. So it would be 61-51= your class limit = 10, then the midpoint is divided by 2, so 5. You CAN do this kind of thing with uneven class sizes, such as 0-60, 61-70, etc, where your lower class is a whopping 60 (midpoint of 30). You just have to multiply that frequency by that specific midpoint.

[@talhatofeeq8122]

Why n - 1

[@thee-content-creator]

Awesome video

[@ashleymuyambo9384]

i swear you sound like Gabetheguru

[@lydiashiyeyemulama4691]

Thkz xo much

[@pepitobenegas]

I hate my statistics teacher he just doesn't explain anything

[@corvu558]

why are you so awesome

[@TechnoSan09]

Pls tell someone why for standard deviation he's putting n-1at the denominator isn't it just n (Freq sum)

[@andrewjustin256]

I don't why I am jotting down this text, but when you teach chemistry, physics or math, you prove that they are black magic ✨ which is only comprehended by YOU and now you are shooting off the hip, flinging them to people faces: "hey, here you go, here is another magic potion; just dump it all up in the witch utensil and simmer it until the liquid turns olive green. Then, you will be a berserk scientist witch." Pardon my French! But please quit this funky, monkey biz.

[@marcogucila9982]

hello! 151. 2157 into 12.3??? Paano po nagawang 12.3 iyong final answer sa standard deviation?

[@muqadasfatima3022]

Sir kindly tell me that this is the sample grouped data formula ? And whats the population gruoped data formula ?

[@luvelyjay]

Another EXCELLENT video!! I wish I could this 100 thumbs up! Thank you!

[@jonahjonesalemania9486]

your voice. one can fall in love with

[@djfhsusbruh6698]

To all Americans and Europeans making memes on Indian guys on KZbin teaching Math , You have this guy. Secondly stop those memes and Stop making life of people like me harder by making those memes.

[@PRISCILLABURLISON]

THANK YOU! this put everything in perspective!

[@matthewnggametime2537]

Are you sure this is from secondary school? I already know this even i am 12 years old. NOOB TEACHER

[@almaazul1511]

why is the process so long??? I feel like it's so much unnecessary work as you started working more and more through it. my professor uses only 3 columns to find variance and standard deviation for grouped data.

[@theodoresweger4948]

I did an experiment with my HP Prime and figured how to enter every data point not as a group by using tthe list functions.. same answers Thank you...

[@susanadhiambo5494]

How can I distinguish between type of data that when calculating variance I divide it by N-1 and that to use whole N to devide help me im getting confused and my exams are near

[@mathewmzee8963]

Thank you so much, your videos have been so helpful

[@romain5617]

E mercé le sang

[@sibusisomdluli1605]

On the last one why do we have 90-100 because now the intervals are no longer the same. Aren't we suppose to have 90-99?

[@valtenkerry7971]

Grate ❤️ If marks are given and students number are not given how would I calculated the deviation in the table given

[@Rick-uy9oy]

The frequency for finding the mean should be total frequency rather than just 'frequency' right?

[@muangealice4478]

why N-1 though

[@monroemullinix5974]

I believe that it is common to use the sample standard deviation formula when dealing with frequency tables to account for the uncertainty (gives you a little larger variance). You can use N. This is the easiest version of the formula: σ = √ ((Σfm² / Σf) - µ²)

[@herbaltalks]

Can't we apply the formula as n-1 for this question ❓ how to differentiate sample and population

[@ntambidean3016]

hei man thank u so much, please anyone who new how he calculated to get the 7th colum ...please

[@neilsklar3509]

To calculate the values in the 7th column, square the values in the 6th column. For example, in the top row, the value in the 6th column is (-24.7). (-24.7)^2 = 610.09. 610.09 is what goes in the 7th column.

[@nirbhaysinghtanwar8439]

There you realize the value of calculators . Unfortunately calculators are not allowed in my country so we need to do all this calculation in our mind only which increases the chances of calculation mistakes alot . 😐

[@abdullahibrahim7030]

Why is the denominator n -1? I was taught it's just the total sum of (f) i.e sigma f

[@spitman6762]

But this is only for the sample, not the population. And for frequency I would use n.

[@Dereck27]

I’ll never learn this. I understand but have no way of remembering this nonsense step by step

[@roba2824]

organic chemistry : how can we calculate the standard deviation of grouped data me : That why I am here

[@Skylark-ns1mz]

why n-1 ? why not n? sum of f is equal to n. Then why did you write n-1 ? Pls clarify

[@claytonmoyo7836]

this is a wonderful work i enjoyed it in preparing for my exam,s

[@VictorOrdu]

Great video. How do you solve the case where the lower or upper bounds of the first or last interval, respectively, are open e.g. "90 and above" or "less than 50"?

[@surbhi1353]

Hey..!! Can You Help Me Out!! The formula of SD for Grouped Data is root over submission of {f(m-X)^2} whole divided by "n" But He has written divided by (n-1)

[@VictorOrdu]

@@surbhi1353 For sample data, SD is always computed with n -1. This is to allow for 1 degree of freedom. You divide by n only when working with population data. To understand degrees of freedom, try watching this kzbin.info/www/bejne/jHrPh4qbirZjrNU

[@Donirexian]

This whole process is probably the most annoying thing I've done on tests

[@roxgregorio4132]

thank you so much for this vid.. I learned a lot..

[@ninsiimaremy6880]

as if they are different formulas of variance? = sum of x-x^/n-1

[@juanitamarievalencia8007]

You’re The Best! Thank you so much, God bless you!🙏🏽

[@Suggu09]

Anyone from India 🇮🇳. Last frequency is wrong.

[@bonifacerizinde292]

You are genius