Range, variance and standard deviation as measures of dispersion | Khan Academy
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- čas přidán 22. 08. 2024
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And here i am, 10 years after this was posted, learning more here in 12 min than my course in an hour
Thank u from the heart of mine, khan academy !
I played this at 2x speed to learn it in 6 min
Same lo
@@vincentdrew2194 That’s not smart, you might not understand everything because your brain can’t catch up. Don’t try to get everything done as quick as possible, sometimes it causes mistakes
reviewing simple explanation after hours of complicated lesson often give you a new understanding and you feel enlightenment.
I am taking a Statistics class online and YOU are by far the BEST thing I've come across! Your explanations are clear and thorough. You cut through all the STATISTIC jargon and allow the student to conceptualize the theory of basic statistical analyses & problems. You are truly Gifted!Thank you for sharing your knowledge and Passion.
This made so much more sense than my university professor. Thanks a lot!
great work but #are so small and the board is so dark?
Harijs Ijabs why are you learning this in university? I'm learning this in the 6th grade
bcuz we all have specific concepts we are learning in college such as criminal justice or law or engineering. But there are a few courses that you have to repeat that u've already learned in middle and highschool. Thats why kid.
+FloydFilmz why'd we pay thousands to repeat what we've already learned?
@@azimtwice idk
Please never delete your videos. I am also 10 years after posting learning this stuff and you are the only one who explained it the way i could understand and use it. Youe helped, help and will help millions of people. Thank you
i cried cos this helped me so much
did it sound something like trololollololololoololollololol
***** Right? Isn't Khan amazing? Khan Academy makes me realize that math isn't so bad when explained properly. So many teachers and books explains things in a cryptic manner. Khan explains this stuff in layman's terms and it just clicks.
Did you pee yourself too?
Same!!! In class I was like what is this even and here I understood it 😂🌸🌸
JJ not math, its statistics.
Oh my god yes. Not all superheroes wear capes
Plot twist: he was wearing a cape
@@lkerzgrl24 Plot twist. OP is talking about Iron Man.
@@whitewalker608plot twist he is talking about Superman 😂
Plot twist. The entire plot has become twisted.
This guy has done so much on Khan Academy, he should be nominated for the Nobel Prize in Education. If there isn't such a category, they should create one
Everyone is talking about their professors in university and how they're useless like 7-2 years ago I'm here in 2020 trying to figure this out in high school because I hate remote learning.
that sounds very difficult dear, i can't even imagine having to do high school right now. i'm sorry you have to go through that
same
me too
@@Lillith9008 thank u for being compassionate
I have studied these concepts in at least three different classes and never understood them as well as I do now. Thank you.
There am I scrolling down and liking every comment coz I can relate to them
Seeing how you have 142 likes....... I wonder
Khan academy... helped my 14 year old self, and still helping me at 24 years old, God bless you.
You know Mr. Khan, you and you alone are the reason this program works so well. What you teach is no different than a university professor, but the way you teach it squeezes more information into a 12 minute video than I'll get in a 50 minute lecture, and I understand it much better. I think I speak for everyone when I say I wish you were my teacher, you'd be absolutely perfect at it.
Amazing teaching skills, i've struggled to understand this in university for the past 2 months, with my prof being of little use. first time watching this 10min video and i completely understand it now! Thank you!
just goes to show these universities are so overrated. they don't teach anymore. About to graduate myself and it is so funny what university teaching has become.
Learned more with this video than the first 3 weeks of college with my useless professor
Hold on you r learning this in Uni then why am i learning this year 9 or 9th grade
AUstralia IS messed up
College?
We're learning this in grade 9 though
@@herat3158 thats what i said but in australia we call college uni
I’m learning this in 7th
@@lily-er5xt yeah, same.
If only you guys could see how the teacher teaches this subject at my university...You'd hate this subject i guarantee. She straight up reads solutions from the guide book without explaining whats happening or why we are doing anything.... Thank You So Much Khan Academy!!!
Currently a history major with a minor in political science. Took statistics in high school and again in college but this just made so much sense. To anyone reading the comments, watch frequency tables first and then start looking at this video. It takes15 minutes for both but you'll appreciate so much math quickly.
Very well explained. However, I find another explanation stating that the denominator in variance calculation should be n-1, which in this case should be 4 (5-1=4). Please clarify. Thanks
+Saul Matakarawa I believe n-1 is to calculate the sample variance.
Not 100% sure, but from what I remember.
somebody else explained please
vortex.ihrc.fiu.edu/MET4570/members/Lectures/Lect05/m10divideby_nminus1.pdf
Check page 2
Sample Variance’s denominator is n-1. Population variance’s is n
@@pppkaew4297 thanks
Your method of teaching is comprehensible, thanks
You're so clear and cut through the jargon so well that it's actually making me mad. I spent so much time in college trying to understand this stuff and if I would have just watched these videos instead I can't even think about the amount of time and effort I would have saved. Great stuff
I need Sal to take my SAT for me.
Thank you u explained it so seamlessly 😭👏🏽. U save me from failing a test
13 years later, yup learning from here more than my professors
The most helpful explanation about standard deviation I've ever watched. Thank you so much, Sal!!!! You're the best math teacher in the universe.
Khan, you legend. Needed a quick primer on this topic. You are the man.
I been sick for the past week and my friends told me about this because they are learning at school so I got worried since they said there's a test tomorrow but this helped a lot THANK YOU now I'm ready
Any time you feel struck in mathematics, you tune into Khan Academy where Sir Sal explaining the concept so easily.Another day is saved,thanks to Khan Academy.
This is the "Population Standard Deviation"
For the "Sample Standard Deviation" we replace n with (n-1) to ensure that all desirable properties of an estimator are retained.
I thought it was n-1?
Exactly
You have been helping me pass university classes for the last decade.
You're a very important person in the world.
This is amazing! I thought I hated stat until I watched the video. It turns out I have a bad teacher lol . The teacher who made this video made it simple and conveyed the meaning in a great way! Thank you:)
From algebra to calculus, to history, and also to statistics?! WoW! so amazed. Is Sal Khan the one that discuss in most these videos? Is he a genius? Or other way around.
Thank you so much for this!!!! ♥️ You’re a blessing! ♥️🙌🏼
such a great breakdown!! thank you!! you explained every step so that I understand what I am using to get each answer.
Thank you so much. This is so helpful. I highly appreciate the time and energy taken to prepare this to make this available for free.
a video explaining sample variance and population variance would be helpful.. (my synapses are shutting down)
Dude, now im ready for my periodical test, tommorrow !! I really appreciate you pal !!!
hopefully you found that useful... it was the most easiest explanation I got on the internet..My university life started a few months back (online semester ft. Corona) and I am taking a Stat course right now. My teachers explanation was really vague, it's like he(my teacher) is trying to hide something from me. but this actually cleared everything up. Thanks Salman. One day, I will be great teacher like you inshaallah.
Oh my god, this never made so much sense before...thank you so much!
This is so helpful!! THANK YOU. You actually repeat what you're doing to help to get it in our brains and for me, it works! I didn't have to keep scrolling back. (And it also helps that you don't have a ridiculously boring monotone voice like a lot of the people who make these maths videos do)
Awesome video and great explanation. But one quick correction, 9:48 Distance can't be negative or zero.
You spoke at a great pace and very clearly. This video was very helpful.
I would like to know what the answer to evilshenanegans' question is though.. and william's question on negative numbers and range...
I don't know why but I am in love this guy's voice.
And yeah the lectures being the first.
I studied finance in uni and our master could not explain it as simple as this in a whole semester. thanks
Seriously saving me in my college class. I didn't understand any of this, it's amazing what a difference a GOOD teacher makes.
Is it just me or does he sound like old Ted Mosby? Great video btw, I've been watching them before class and they are super helpful!
I don't have enough words to thank you! You helped so many people, including me. Truly, thanks so much :)
You rock - as usual.
You are sooo amazing.how many people have you helped ???
You will never know
Khan academy at it again with an awesome explanation and breakdown of statistics. Thanks very much.
Ha, watched Khan academy vids when I was 10 and here I am 6 years later using them to help me with my as levels
Oh wow!! I don't normally comment of CZcams videos, but you just took something that I found so confusing and complex and broke down until it was simple! Thank you ever so much
Tanx God i found the best teacher here even you tube.nung nag aral ako walan akong naintindihan.thank you so much Sir for your help.God bless u Sir
This is cool. You have helped me a lot. Thanks to you 😊
I've also watched your videos on several topics in physics. Galing nyo po!
It's summer I'm 13 and I'm learning it's my best summer yet
I understood standard deviation from my math book I just didn't see that variation was standard deviation without it being square rooted it's so easy
Bro why am I learning this in year 7 💀
Found this vedio in my 3rd year of med school and was saved in Biostatistics. Alhamdulillah
I was out of class with my friends when my lecturer was teaching this thank you so much.
I calculated -20 squared and it was -400. I am not saying you're wrong I just doubt that equation. But other than that you're an amazing teacher. Keep up the excellent work Khan!
your videos are too good and i think u are doing a great job
For the square root of 200 I get 14.142... How am I understanding this wrong... Great video. You are a really good explainer.
You did a great job. I followed the lecture and I could not understand. I saw your video only once and I realize that it is very easy. I think because you explain very well. thank you very much.
Thaaanx
Fantastic explanation I've always found range, variance, and standard deviation frustrating. This video really breaks down these concepts in a way that's easy to grasp. Please share more such videos. For anyone else struggling, this video is a game-changer. Plus, I've also been using free textbooks from SolutionInn to better understand these concepts, and they've been a huge help alongside this video. Pairing it with resources like SolutionInn, Chegg, or Course Hero offers extra practice and explanations that solidify your understanding. Thanks for making this topic less daunting!
The video is correct because he dealing with a population data set (also evident by the use of the sigma symbol). He explains this @ 4:45 - 5:09. You only use (n-1) when you are dealing with a sample data set (where you use "s" and not sigma).
yes indeed this explians it a bit better than all the other class material. Thanks!
Thank you. You are really good explaining !!
Why did you divide by 5 instead of 4 ! I know that you have to divide by the number of data but in the standard deviation you have to subtract 1 from the number of data, so it should be 4 not 5 !? could someone explain ?
Ohh I just figured out that you calculated the standard deviation for a population not for a sample !!
now it makes a lot of sense to me
thanks !
What is the standard? Population or the Sample?
he calculates population standard deviation
did you ever find the answer? cause i was thinking the same. thanks
population is when you have all the data that you need, thus only dividing by n, when you only have a sample of the data, you divide n-1
Everybody, please check your formulas. This video is almost correct, but he forgot that it's supposed to divide by (n-1). That means that the whole thing should be divded by 4, not 5 for the variance problems.
Your videos really help me get through my statistics class, thank you 💕
The perfect way to understand the variance and the standard deviation ... Thanks KHAN Academy
Your explanation is very clear and simple to understand. Thank you.
Simply , Its Great . Thank you
1. explain how you determine if a graph has high or low variability
2. Explain how you determine if a graph has high or low statistical bias.
3. Explain the difference between stratified random sampling and cluster sampling.
very useful. I'm taking QUAN201 and I wish I had you as my instructor 'cause mine really sucks
I wish u were our bio-statistics instructor , my life would have been so much easier
OMG! I love you! I finally understand this now!
So happy!
Thanks so much (from Southern hemisphere)!
You're a rock star! I totally get it. Thank you.
how does the squire root of 400 become 2 ?
These people are in college learning this while I'm still in middle school learning thus during social distancing
@Yash Verma I wasn't trying to be
Why are you mad?
Teacher: "This is the mean. the MEAN. The MEEEAAAANN."
Average Student : ".....what?"
Thank you so much. This.. This is exactly what I needed. It made me realize I'm not slow nor stupid it just depends on who the teacher is.
Here I am, trying to actually understand these concepts 8 years after school, and this 12 min video made me feel like my schooling had failed me.
I love your explanation really but I am bit confused with SD (standard deviation) but I will go back toy book and listen to this again. Thanks 🙏🏿
In this example he's working on population so he uses N (5 -> entire population). However, we use N - 1 when dealing with a sample of the universe.
this is SUCH a good video. i am doing a course in stats for uni and struggling so much because it's been years since i did maths (never been good at it) and i'm so happy i found this video because it's cleared up so much of what was confusing me about this whole SD vs. variance business
now i get it thank you very much !
I normally just like the video but, this one deserves a comment. Good job, great explanation!
Thank youuu omg I can take my exam tomorrow in stat without any doubts with my answers
I know these stuff 100%, but I need to understand these stuff with 300% confidence. Thanks for the upload.
You saved my future and my mental health
First time in my life I understand what is variance. Thank you so much!!!
If i hadn't left an entire math exam until tommorow this would've helped. thanks for the knowledge though.
Haven't really used Khan Academy before, but I used this for Economics and makes perfect sense. Thank You.
you are an amazing individual, thanks for making it simple
Thank you so much for your video and explanations .I started Statistics classes recently and i also learn more from here than from my professor .It helps really thanks a lot again
The sample standard deviation of the dataset 2, a, 12, 18, and 30 is 10.8 (correct upto one decimal place), where a is an unknown quantity. Then, the value of the sample variance of the new dataset that is obtained by adding 5 to each number of the given dataset is __________.
This video has helped me a lot to understand standard deviation and variance.Thanks a lot Khan Academy.
Thank you for making this more clear than the professors we pay thousands of money to
thank GOD for you!! I was stressing in class. you just made it super simple for me!
The video helped me a lot in understanding Standard Deviation.
Just when I began to understand this standard deviation and variance concept, I watched this video. Now I am so confused. Back to the beginning. With another tutor. Statistics are so HARD!