# Statistics: The average | Descriptive statistics | Probability and Statistics | Khan Academy

5711 ratings | 2001691 views
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katya cocone (6 hours ago)
SO NOBODY'S GONNA TALK ABOUT HOW THE WRITTING IS GOALS TO BE WRITTING ON A COMPUTER?!
Arun Keshav (7 days ago)
Sal, you are outstanding, like your videos and get benefitted a lot. Regarding the one on which you spoke of Population and Sample Variance and lowering of the denominator for a better estimate of sample variance representing Population Variance, would you not look into the fact that the statistic would be valid only for representative samples. Would taking random samples also lead to big difference in sample and Population variance values?
Himi (28 days ago)
this is so old, squared frame and everything. OG
jack makson (1 month ago)
The quality control department of Atherton Mills specifies that the mean net weight per package of cereal should not be less than 20 (μ=20) ounces. Experience has shown that the weights are approximately normally distributed with a standard deviation of 1.5 (σ=1.5) ounces. A random sample of 15 (n = 15) packages yields a mean weight of 19.5 (x̅=19.5) ounces. Is this sufficient evidence to indicate that true mean weight of the packages has decreased? Hint: (H0: μ≥20, HA: μ<20), Z=x-n, α=0.05
how to find larger average ???
Shaima Mohammed (2 months ago)
333331000 why did you consider 100 is only one number ?? I consider it 3 numbers with sum 1+0+0= 1 so the mean is 16/8=2 the media is 3+3/2= 3 please explain more ? thanks
Tarek Waleed (3 months ago)
love you 😍
Tatevik Galoyan (3 months ago)
it was so simple and interesting
Demetra Siountris (3 months ago)
Excellent video! Very succinct. One of the best I've seen.
Xin Huang (4 months ago)
thank to your videos, my statistics can be saved! :)
Lucas Batista (4 months ago)
What is the difference between this playlist and the Statistics and Probability course at www.khanacademy.org?
Azola Ramona (5 months ago)
Khan never disappoint me :)
saleena shiekh (5 months ago)
school should be youtube frrom know on,,,
Sunny Yoda (6 months ago)
Thank you so much khan academy you are the best!!
Neno_ Crocs (6 months ago)
I've watched the whole playlist and honestly you're a great help! Thank you so much!!!!!!!!!!!! Really... I'm so grateful!
Mukul Thakur (6 months ago)
house that costs a trillion dollars ( ͡° ͜ʖ ͡°)
Deshmukh Ganesh (6 months ago)
Thank you for providing free knowledge. I came here from channel - Siraj Raval. To learn Machine learning, he said we should know Maths, statistics and probability and he gave reference to your channel. Thanks both. And love from India, specially from Mumbai.
Ivan V (3 months ago)
+Usha Dev they are
Usha Dev (4 months ago)
Same here ...me too came from chennal called siraj .. let me know this classes are useful for machine learning.????? Plz reply.
mailvarunnow (6 months ago)
Exact same reason why i begin to watch this video to learn Machine Learning, i realise i should know stats which i always avoided.
Casey Gibbs (6 months ago)
Like... I'm in one of the best universities in my country studying law. Yet this dude explains it clearer so I'm here :D
Toufiq Hasan (6 months ago)
this black board is so irritating
4 Fake (7 months ago)
A free stats tutor. Lol I'm finessing.
Bender Bending Rodriguez (8 months ago)
and this is the reason I am an alcoholic...
Nikhil Bumb (8 months ago)
what is the total time of the Statistics playlist?
Maricarmen Frías (9 months ago)
I guess there are better ways for teaching this basic concepts with graphics instead using just the electronic blackboard, anyway maybe for some people works better.
Moosa K (9 months ago)
I want a trillion dollar house
jeremy Lee (9 months ago)
Why its quality is so bad?
Shivam Gupta (11 months ago)
Is this course on statistics sufficient for machine learning ?
Usha Dev (4 months ago)
Same here ...??
D6L Swings (11 months ago)
2+2 is 4 minus 1 that's 3 quick maf
Stephanie Lynn (11 months ago)
For many years, my family and myself, have used your channel. I find myself here; yet again. Thank you. I am getting so close to graduating with my Psychology degree. To get a better understanding, you just know how to use proper word choice and I am grateful for that. Thank you so much!
Leandro Albero (11 months ago)
Ralphie McSkagaway (1 year ago)
Hey Sal, 'arithmetic' is an adjective in front of mean, and is thus pronounced ARithMEtik, not aRITHmeTIK, i.e. primary and secondary stress on 1st and 3rd syllables not 2nd and 4th. Thanks. It just kinda bugs me on a vid that is otherwise great.
xiumin's mochi (1 year ago)
1+1 is 2 2+2 is 4 QUICKMATH
Eklavya Singh (1 year ago)
Hello Mr. Salman Khan, I like your teaching style and your videos are very helpful. A small suggestion, you talk a lot about little things and that feels distractive, so it will be better if you stick to the main concept and decrease your intensity of using small talks in the videos.
I'm currently taking my Master's and it's a shame that here I am, studying Statistics through Khan as if it were my first time. Thank you so much! You're a big help!
anas kh (3 months ago)
Don't feel bad about it; human forget all the time, so it is good to refresh your memory here. Wish you good luck.
Chris B Kirov (1 year ago)
The whole playlist is great, but the last 20 videos (49-68) are simply amazing - clear, concise and very informative. Note: 57 should be between 53 and 54.
Mahesh KOTHARI (1 year ago)
thanks sir
when will youn add new material?
this material really help me in learning statistic
Justinian's Legacy (1 year ago)
I've never been good at the quantitative side of things. Now that I'm looking at grad school I'm worried about falling behind. Probably going to have to take stats in my last/second-to-last semester, and I need to keep my GPA up at the same time... Looks like I'm binging this series over the summer...
Kerri R (1 year ago)
Sal literally knows everything. Lol
Ashhar Kamal Hashami (1 year ago)
Nice video, very helpful.....By the way, The way you say "Three" (8:54 to 8:57) is funny
Kailash Karmakar (1 year ago)
Thanks KHAN ACADEMY, it is awesome. Respect and Regards. Kailash
Pankaj mohanta (1 year ago)
Khan academy.Please make videos on experimental designs of statistics-CRD,RBD,LSD etc with detailed explanation.🙏
Jort Evers (1 year ago)
2 + 2 = 4 MINUS 1 THATS 3 QUICK METH
Dapper Mink (1 year ago)
Jort Evers lol i was about to comment this
Nik Sallé (1 year ago)
can someone help me with this problem??? please??? what are the odds of picking 3 of 65 numbers correctly. they dont need to be selected in the same order. any help would be great, thanks.
Ahmed Silk (1 year ago)
Dear Sir, thank you for the vidoes.. is it possible to know the software you are using for producing these videos? thanks
amber ashfaque (1 year ago)
I wanna a complete derivation of Pearson chi square is any body help me for this?
- smoke (1 year ago)
جامعه الملك سعود شله
Popese Siitia (1 year ago)
4:23 2+2 is 4 minus 1 is 3 quick mafs. I really need to focus
cameron clare (1 year ago)
Your videos are a godsend to autistic students like me. Very systematic and straight to the point, and not overstimulating. Thanks man!
Nachiket Belwalkar (1 year ago)
2 mins silence for those who disliked this video....
Nex Isle (1 year ago)
I love you man. When you explain math its like you're explaining a story or something. You don't explain procedures, you explain both procedure and reasons. And because you use accurate terms for every specific situation makes me understand the real meaning behind each word. Man you're one in a million
Fares Van Lierde (1 year ago)
awesome =D I'm glad I found this channel on my first university year !!!
Bhavana Penmetcha (1 year ago)
Can someone please tell me where I can do practice tests for this statistics playlists???
Svetlana Escobar (1 year ago)
I wonder, were the 89 that disliked the video were statistic teachers??
Lucas (8 months ago)
My Data Science teacher told us to watch this/
Nurudeen Abdul-Karim (1 year ago)
LOL!
Sawyer McBride (1 year ago)
Anyone not taking a class, but just learning?
NFL WEEKLY NEWS (1 month ago)
I am working on a project for my YouTube channel. I hope the video comes out this coming week or the next one
Finally We are 100
Charis Baafi (3 months ago)
+Goldberg Sam Do you have other materials you can suggest for me?
Charis Baafi (3 months ago)
+Daniel Dilly Same here
Daniel Dilly (3 months ago)
Yeah. I've been intrigued by neural networks and machine learning in general and I'm having to learn more math to make sense of it all. This is what I do in my free time, haha.
Hi. İn which program or platform or technology do you use for representing information in a such way? Writing deleting etc
Stephanie M. (1 year ago)
Haven't taken math since 10th grade, and I was awful then. One video in and I'm already optimistic that I'll be able to understand statistics! Thank you so much!!
Sino Lingo (1 year ago)
Love it! I think real world school needs revolution!!!!
Daniel Javier (1 year ago)
Thank you for helping me pass Elementary Algebra high school today. I WAS going to be in a non college credit remedial course. but not anymore. scored 61 on the 1st test(Accuplacer) and scored 88 today for my retake
Morten Balling (1 year ago)
This is an excellent series of videos. Very clear and informative, while including the viewers intuition. I think however, that some ultra basic understanding of Philosophy of Science, will help everyone's motivation for learning statistics. You have to be kind of nerdy one, to really appreciate this math, but philosophers like Karl Popper has pointed out, that no matter how hard we try to measure something, we can actually never prove, that we will measure the same value the next time we try. Try to wiki "Popper Black Swan" for an excellent example. This uncertainty in any science is perhaps the main reason why this is important stuff. It is kind of a, what Kuhn would call, mental paradigm shift, once you understand the meaning of all this, but it makes statistics a lot more interesting, than just learning the formulas. Enjoy :)
Amr Elsharkawy (1 year ago)
Is their a written material for this series of lessons?
Da’Nica Starr (1 year ago)
I remember some of this from elementary school but I'm using the playlist to study for a midterm
Fiona Bennis (1 year ago)
i have a moc gcse on stats tomorrow and it's 1am i am revising through this.
Spring09 (1 year ago)
He is my Guru. The voice in my head
Kevin Portillo (2 years ago)
when I got to college I started noticing how important math actually is. And recall I was taught Average, Median and Mode in like.... 6th grade .... O__O
Vikermajit (2 years ago)
Your explanation makes statistical concepts understandable and comprehensible. I used to have many fears and doubts in statistics...now I am more confident and enthusiastic to attempt to solve stats problems. Thank you Mr Khan, and god bless.
jake parker (2 years ago)
how many times can you say indicative in 12 and a half minutes?
Ameera Nasser (2 years ago)
Sumant Jha (2 years ago)
brightblueeyed (2 years ago)
literally paying 5 grand a semester and free youtube videos teach me more. I'm taking a class right now called Vegetative Sampling Method and Design and my prof expects us to know statistics from day one, even though its not a prereq
Deshmukh Ganesh (6 months ago)
Please pay some money to him as well, to support channel.
He has definitely upgraded his PC and his handwriting
ToastanfJam (2 years ago)
Thanks, my teacher is useless that I wanna smack him with a brick.
Don Caleb (2 years ago)
I HAVE EN *EXAM* IN 2 DAYS!!!!
Silver79 (2 years ago)
Found this just in time for my stats class tomorrow
Michael Cruz (2 years ago)
What statistical test to use when the researcher likes to know whether note taking has effect on students academic performance based on the quantity of their achievements (whether they became honor students etc.)? The basis for achievements are: How many times did they achieve High Honor, Honor, Principals Lister, Top Student in class.
what if we omit that larg number and then take an average
From Kat (2 years ago)
It would still be 3
The Accounting Guy (2 years ago)
Great video!
mervelerden biri (2 years ago)
tysm
Jyanyy (2 years ago)
Thank you VERY MUCH FOR MAKING THIS MATH WORLD EASIER and CLEARER instead of professor giving BOOK Definitions and following examples..(sorry about caps)
Patrik Banek (2 years ago)
THIS SO MUCH CLEARER THAN SCHOOL
From Kat (2 years ago)
Right
Andrew B (2 years ago)
For real though my professor is so under qualified to be teaching this. She assumes too much in thinking her students understand everything she spits out as fast as possible then ends class early so she can go do whatever. She doesn't break anything down or explain things properly. She's a part timer and I don't think she realizes that a lot of us need this credit to graduate in the spring but here we are, barely passing or just below failing. Khan Academy should just do universal online courses for statistics and other math course. Better than literally any other institution that isn't a prestigious and highly recognized school like McGill, Harvard, Yale, etc. So thank you Khan Academy. You might just be the only reason I graduate and get this Stats credit. Paying all that tuition money just to teach myself by watching online videos by Khan... The education system is broken.
Honesty23 (14 days ago)
The EDUCATION system is not broken its not for learning but brainwashing .. Dont be confused
Honesty23 (14 days ago)
Sounds like a government governing the time and what teachers teach.. This happens everywhere and its why i got a bad grade in calculus.
Yellow Mellow (4 months ago)
You should talk to your teacher and let her know in a respectful way.
love myself19 (8 months ago)
Omgggg this is literally my chemistry lecturer literally ...she is so bad the worst lecturer i had ever seen ..im so sad and dont know what to do
Michael Baugh (2 years ago)
Rana Granger (2 years ago)
these old videos are much better than the new ones
Nick Baker (2 years ago)
How do you make videos using paint?
Ahmed Morsy (2 years ago)
what is the tool he is using in writing ?
anthony caceres (2 years ago)
this is so boring why is he on my suggested list??
sciencelearnremember (2 years ago)
WHAT IF the set contained 1,1,2,2. What would the MODE be?
Arman Khan (2 years ago)
both 1 and 2
sciencelearnremember (2 years ago)
+OtherRooster Very interesting and helpful indeed!
MJ Tacloban (2 years ago)
+OtherRooster Thank you!
OtherRooster (2 years ago)
I believe they call it "Bimodal." Essentially, when considering mode, you can come to three conclusions. So if your set is 1123, the mode would be 1. If your set were 11223 it would be bimodal with the modes being 1 and 2. However, if your set were 112233 there would be no mode. So, you can have: 1 mode, bimodal, or no mode. Hope I explained it well!
Will Hall (2 years ago)
Wow. You lost me in 10 seconds with the terrible mouse cursor writing.
Ryuseiken Kyokushin (2 years ago)
Can any staff member contact me?
Ryuseiken Kyokushin (2 years ago)
must be japanese hot chicks :P
Rana Granger (2 years ago)
XD
fylar crockley (2 years ago)
In regards to a daily sweepstakes, does it matter if one enters every day rather than one time only? which way are the odds better? Thx
Gandalf the Grey (2 years ago)
Play it on 2.0 speed. Thank me later
Gandalf the Grey how?
irkenus (3 years ago)
His life is the sum of a remainder of an unbalanced equation inherent to the programming of the Matrix.
Sohaib Ali (3 years ago)
Hey SAL ! you are like a Friend Thanks Bro
saskue de boss (3 years ago)
he is good
Kiki Meeks (3 years ago)
OMG, I actually understood that!! I was even answering questions before he gave the answer. That was fun, I never thought I'd say that about stats. I find this impressive since the last stats class I took was back in '95. THANK YOU , Can't wait to watch the other videos.
Burak Gurpinarli (3 years ago)
👍🏼
A A (3 years ago)
Thank you! Its a very useful lecture!
K (3 years ago)
Great video! Love the way you exhausted examples and left the listener with no questions.
Kyaiaia Kyaiaia (3 years ago)
oooohhh u organize them then take the middle number i just remembered i took that ages ago.. i wonder if university is gonna be harder though
Saswat S Nayak (3 years ago)
thank you sir