The Shape of Data: Distributions: Crash Course Statistics #7

Рет қаралды 555,625

Күн бұрын

When collecting data to make observations about the world it usually just isn't possible to collect ALL THE DATA. So instead of asking every single person about student loan debt for instance we take a sample of the population, and then use the shape of our samples to make inferences about the true underlying distribution our data. It turns out we can learn a lot about how something occurs, even if we don't know the underlying process that causes it. Today, we’ll also introduce the normal (or bell) curve and talk about how we can learn some really useful things from a sample's shape - like if an exam was particularly difficult, how often old faithful erupts, or if there are two types of runners that participate in marathons!
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Пікірлер: 194

@asterdan712 5 жыл бұрын

This is what true education of the future looks like. Simple, creative, fun to watch, highly educational, and very graphic. And a great job by Adriene Hill and the entire team for the quality of the content. Keep it up.

@abrahamel-gothamy6472 6 жыл бұрын

Is there any way that you could release transcripts, outlines, and/or notes for your videos? Especially the math-heavy ones. I think it would be easier to learn the information if there were a guide

@stephenj4937 6 жыл бұрын

If you click the 3 dots to the right of the thumbs up/down and share buttons, there is an option to open a transcript.

@ok-vb6lr 6 жыл бұрын

oh my god.... thank you.. i wish i knew this earlier but thank you!! :D

@safflower_s 6 жыл бұрын

i had a course on statistics about two years ago, and wow, i'm really thankful for this course being here, because it's nice to be reminded of these things

@nathanalgren288 4 жыл бұрын

10:06 : I think it should be mentioned here for the more mathematical-minded folks that that's a difference between what's called 'statistical probability' and 'theoretical probability', and a general principle is that statistical probability approaches the theoretical probability as the number of trials approaches infinity (which could be thought of as a limit at infinity).

@samabplanalp2801 4 жыл бұрын

This fundamental stuff is so important, yet overlooked in most academic statistical practices

@kareemjeiroudi1964 5 жыл бұрын

I really like the animations in this video, especially that you can then see how changes in the data distribution affects the plot. This way it starts to make more sense to me.

@oldasyouromens 6 жыл бұрын

I'm taking Stats this year, and we're on significance tests, but I'm watching all of these too because I think Stats is really, really cool.

@voltairesarmy6702 6 жыл бұрын

Grace Sophia stats gets super cool! Eventually u'll see the connection between all sorts of stats that initially seemed to be completely different, like ANOVA and Linear Regression.

@davidli105 6 жыл бұрын

Just took a test on that today lol

@jacobo2234 6 жыл бұрын

what human are you? I toke ap stats as a joke and I got in, Im taking six aps this year is stats is one of the hardest

@oldasyouromens 6 жыл бұрын

Jacobo OH, it's definitely my hardest AP. But it's also my most fun and most rewarding. I'm only taking four (and one was a semester class I don't have this semester) so I'm just going to say "I'm sorry". Six AP classes is a hell of a lot.

@rohitsagar6432 4 жыл бұрын

Great video - really helpful. Like the touch with the bell curve /box plots/pie charts in the background!

@patrickmeehan6856 5 жыл бұрын

I love how this series mixes the answers to big picture "why?" with the more pixelated "what?" and "how?" questions.

@elijahcook5168 6 жыл бұрын

Crash course: music theory

@marcelmukundi5281 6 жыл бұрын

Elijah Cook Yes!

@sofia.eris.bauhaus 6 жыл бұрын

i'd like a course on music theory that uses mathematical language instead of the horrible nomenclature musicians use. and chromatic notation.

@marcelmukundi5281 6 жыл бұрын

sofias. orange I couldn't agree more

@Prince-vi9ri 6 жыл бұрын

YES PLEASE

@AmyBHaddock 6 жыл бұрын

I agree. As a JH/HS instrumental teacher I love teaching applied music theory but I don't always give it the time it deserves.

@suraj__7 5 жыл бұрын

"samples, shapes and their shadows" .. superb writing skills.

@katieharriott2144 5 жыл бұрын

You're videos are amazing and so easy to understand. Thank you! (As I work through each one by one....)

@RodrigoCastroAngelo 6 жыл бұрын

Great video! I'm eager for seeing the other distributions like poisson and bernoulli.

@jojo_beans 6 жыл бұрын

This course is one semester late and could have helped save me from getting a D+ last semester in my Stats class. But D's get degrees, baybee!

@david0aloha 4 жыл бұрын

Since when do D's get degrees? Anything below a C average was below a 2.0 GPA, and put you on academic probation at my university.

@davidsweeney111 6 жыл бұрын

I love looking at the shape of data!

@catirerubio 4 жыл бұрын

Thanks for taking the time to make the video. Sadly, it lost me at the Standard Deviation.

@anshgupta8560 6 жыл бұрын

Thank you so much!!!!! This really helps

@svalbard01 4 жыл бұрын

5:13 if lots of people died young during the middle ages, wouldn't that move the curve/average for "age of death" further left, thus moving the skew (tail) to the right, i.e., right skewed? Right now with the average age of death around 80, it's left skewed.

@al.winfrancis 5 жыл бұрын

When you were explaining how standard deviation changes the shape of a normal distribution, shouldn't the numbers on the horizontal axis stay where they are instead of stretching and squishing with the standard deviation? Because I think that otherwise the shape of the distribution doesn't really change. Please, let me know if I'm missing something.

@wayneemery9276 4 жыл бұрын

good presentation for what was covered, but was really looking for a lot more distributions like chi squared, poisson etc

@johnbagel2560 6 жыл бұрын

Too bad this video didn't feature Ed Sheeran creepily stalking the entirety human population because he likes the shape of their data.

@voltairesarmy6702 6 жыл бұрын

Probably he'd stalk a decent random sample of the population since the sample should have a similar distribution.

@ZamanSiddiqui 6 жыл бұрын

World History With Dan 😂

@benebutterbean2737 5 жыл бұрын

Wouldn't that be Grint doing the stalking?

@porshealewis158 3 ай бұрын

Thanks!

@RodrigoCastroAngelo 6 жыл бұрын

Is there a test we can make on the data to know if a bimodal distribution is actually an overlap of two distributions, or do we need to analyse each case separately?

@AllenLonger 4 жыл бұрын

@4min17sec, is 'standard deviation the average distance between any point and the mean'? I thought MAD (mean absolute deviation) is the definition of that?

@rdvankayahan9753 6 жыл бұрын

Thanks

@ShuvamNayak 4 жыл бұрын

Would you like to suggest any material or reference to follow along with your videos?

@Powerandm.nipulation Жыл бұрын

Are there any specific exercises to solve or some related question sets for each episode or topics?

@JCResDoc94 6 жыл бұрын

my fav part of statistical mathematics is how often she says knobs.

@not_a_human_being 6 жыл бұрын

Uniform distribution often refers to continuous uniform distribution. Dice makes Discrete Uniform Distribution

@theoandolaf 6 жыл бұрын

Love the title. I see what you did there.

@georgia7723 6 жыл бұрын

Please cover linear regression!!

@voltairesarmy6702 6 жыл бұрын

This is a decent resource for regression analysis!

@robertgarcia2689 Жыл бұрын

thanks

@Urbanfour 6 жыл бұрын

Crash Course Music! The science of harmonics and it's application in all the instruments as well as it's evolution from ancient times up to today!

@chouaibbio7673 6 жыл бұрын

I like the bamboo histogram on the table

@davidli105 6 жыл бұрын

Wish they made these vids earlier so it could’ve actually helped me with AP statistics back in fall smh

@juleslee9455 5 жыл бұрын

can someone please tell me where that normal curve pillow on the table is from?!

@dannysmall7914 6 жыл бұрын

All I learned from this. Roulette has 38 slots.

@AlRoderick 6 жыл бұрын

The people who are old enough to have watched Animaniacs are going to be the ones doing better on the countries of the world test.

@SuviTuuliAllan 6 жыл бұрын

Alexander Roderick What about Freakazoid, what can the people who've watched it do?

@johnbagel2560 6 жыл бұрын

What about the people who didn’t have a childhood what can they do?

@AlRoderick 6 жыл бұрын

Suvi-Tuuli Allan they can say Candle Jack and then suddenly dissa

@JCResDoc94 6 жыл бұрын

Animaniacs has been remade

@MarcoCastilloVideos 6 жыл бұрын

Ahahahah

@maryjoannemiranda660 6 жыл бұрын

am i the only one taking a statistics test tommorow???

@noneofyourbee-siness 6 жыл бұрын

Mary Joanne Miranda No sis, me too🙃

@nikolakis2001 5 жыл бұрын

@AvatardSwag 5 жыл бұрын

@@nikolakis2001 same

@naniigraph 5 жыл бұрын

I have a quiz tomorrow

@remaininlight9269 4 жыл бұрын

Same I have an AP screening test

@theurbanwolf298 6 жыл бұрын

I wonder what’s the data on school loans and high earning jobs. Do high earners pay off their student debt(early) or do they even have payments?

@falnica 6 жыл бұрын

I'm a particle physicist and my simulation ins't working and I'm tired so I'm gonna watch this video to see if they mention something I'm overlooking

@voltairesarmy6702 6 жыл бұрын

Fernando Franco Félix I suggest sleeping on it. When my code doesn't work I usually fix it easy in the morning. Once I was so tired I didn't realize I was trying to run correlations on zero vectors. XD

@kyoung21b 6 жыл бұрын

Fernando Franco Félix - Maybe somebody got lazy and left out a higher order term in estimating a cross section that you’re using... just kidding; nobody would do something like that !

@neutronstar6739 6 жыл бұрын

well just pretend to be a particle. Then you know how.

@secularmonk5176 6 жыл бұрын

Play this at low volume while you sleep: Particle Man -- They Might Be Giants

@thearchibaldtuttle 6 жыл бұрын

Have you rebooted the flux compensator? Happens to me every time!

@kyoung21b 6 жыл бұрын

A “theoretical” roulette wheel yields a uniform distribution over final slots but check out the book The Eudaemonic Pie for an entertaining story about a group who took advantage of the slight imperfections associated with any real roulette wheel.

@datas_cat 6 жыл бұрын

I just realized the shelves on the wall are box-whiskey plots :P

@avivaz3038 5 жыл бұрын

If the variance is low, that means that data is squished closer to the mean, so why is pointiness bad (leptokurtic)?

@oversoul7 6 жыл бұрын

What does DFTBAQ mean?

@thegoatman22 6 жыл бұрын

Dont Forget to be Asking Questions

@oversoul7 6 жыл бұрын

Thank you! Already put into practice and shown to be beneficial

@avivaz3038 5 жыл бұрын

If a distribution is normal does that mean it has only one mode? Can it be bi-modal and normal?

@farahzamir2138 6 жыл бұрын

Am I the only one for whom the 'knobs and dials on the machine' metaphor doesn't work? I like this series so far (and love Adriene! Crash Course Economics is a real good series y'all), but this video was a little confusing for me.

@Tntpker 5 жыл бұрын

parameters of the normal distribution function

@retief8987 6 жыл бұрын

I really enjoy these videos! My only comment/complain/concern is that a lot of your examples and expression are North American. I am from South Africa and was fortunate enough to spend a year in the USA but other English speaking people from around the world will not be able to understand expressions like lollygagging etc. Otherwise 5 star!

@nateweinand4209 6 жыл бұрын

The timing of this title was perfect because I totally read it as "The Shape of Water" when I glanced at it really quickly. This comment will be irrelevant by the end of the week... because no one will get it.

@aaronwalters4511 5 жыл бұрын

I don't get it.

@Hassan_Zeiny 5 жыл бұрын

from min6 is good

@JASDKA1 6 жыл бұрын

Somebody reply plz ...kinda off topic but...since we don't count every opinion to have an idea of a the actual picture , and we just take into account the majority...That means the majority is what must be considered? For example 1% < 99%

@claushelge1366 Жыл бұрын

Aaaw, a plush normal distribution!

@AviG36 4 жыл бұрын

I could totally be mistaken but did she make a mistake when she said the mortality age was left skewed. Should it not be right skewed?

@reyrey4993 4 жыл бұрын

yh ur right, it should be right skewed instead.

@mohdshahrul7679 6 жыл бұрын

Ive been watching this video until the end.. And.. I suddenlly remember.. That i need to take my clothes to dobi

@user-vo9vn6bg4z Жыл бұрын

i understand that correlation does not mean causation, but does that also mean that if there is causation then correlation is implied?

@123lightmovies 6 жыл бұрын

please teach us art of electronics for begginers

@davidturner1079 4 жыл бұрын

I totally did not understand the machine example. I'll have to watch again.

@yolandawhite8541 6 жыл бұрын

I'm finally early WOOOOOOHOOOOOO

@meetchauhan2512 6 жыл бұрын

Please add course of agriculture..

@4Ivy 4 жыл бұрын

I want that tiny pillow.

@TylerWatkins101 4 жыл бұрын

The marathon time distributions were for amateur and pro? Because the label said male and female.

@anti_MATT_er 6 жыл бұрын

I just took a data analysis test today.

@JCResDoc94 6 жыл бұрын

whered you take it, to the ohhh watenmdfaikkv c

@BryanLeeWilliams 6 жыл бұрын

I rolled a single 20-sided die 10750 times. The 1 came up 2.7% below the mean and the 20 1% below. The 9 and 15 each came up 0.9% above the mean. Comparing the actual numbers of 15 and 1 that's 639 to 247. Out of 10750 that seems like a big difference to me. Is this enough samples to say that the die is an unfair die? Throughout the process I watched the distribution. It stayed pretty consistent once I got to around 1000 rolls. Counting the 1 as the bottom and 20 as the top, the 9 and 15 are on the middle row directly above the halfway point and are almost opposite each other. The full data 1 247 -2.7% 2 510 -0.3% 3 603 0.6% 4 503 -0.3% 5 587 0.5% 6 559 0.2% 7 547 0.1% 8 513 -0.2% 9 636 0.9% 10 512 -0.2% 11 551 0.1% 12 577 0.4% 13 578 0.4% 14 500 -0.3% 15 639 0.9% 16 482 -0.5% 17 627 0.8% 18 548 0.1% 19 599 0.6% 20 432 -1.0%

@OlleLindestad 6 жыл бұрын

Firstly, I'm curious: when and why did you roll a die 10750 times? How long did that take you? Was it a physical die or a digital random number generator? Secondly, I couldn't resist running some chi-square tests. An overall test of your whole dataset (where the expected frequency of each number is 10750/20=538) generated a whopping chi-square value of 271. That's a measure of how far the observed distribution is from the expected uniform distribution, and with 19 degrees of freedom, we get a p-value of, uh... about one to the minus 46. This suggests that it would be *extremely* unlikely for a fair die to give such a wonky distribution of values. I was curious to what degree this result was affected by the very low number of 1s, so I tested a couple of number frequencies individually against the combined frequency of the other numbers. Turns out, even getting this many nines (observed 636:10114; expected 538:10212) seems very unlikely (chisq=19; df=1; p

@BryanLeeWilliams 6 жыл бұрын

I was going to roll 10,000 but I was bored and rolled some more. I rolled it off and on for several days while I watched KZfaq and Netflix. I wanted to see how fair it was because I bought some new dice, had watched some Matt Parker videos about dice, and thought it would be fun to try out the 20-sided one. (Yep, I don't have much to do; I'm disabled and sit around a lot) Thanks for doing the statistics. It's been over 20 years since I took statistics in college, and my memory is horrible; I didn't know where to start.

@F3V3RDR34M 6 жыл бұрын

@ayushsharma9270 6 жыл бұрын

CrashCourse mathematics required.

@rileyclifton3858 6 жыл бұрын

Hey Y'all

@emeraldemperor2601 4 жыл бұрын

I just realized that the shelf behind her is shaped like a bell curve... XD

@potatofieldsforever4089 6 жыл бұрын

The normal distribution is also called the gaussian distribution

@praveenpingali4062 6 жыл бұрын

Notice the bamboo shoots like a normal distribution

@cristian0523 5 жыл бұрын

I expected to hear the concept of kurtosis

@ahmedhamdy9160 6 жыл бұрын

where is the Arabic sub. for the rest of the corse ?! ):

@yiyiyao7165 4 жыл бұрын

where can i get one of these gaussian plushies on the table

@josealonso7478 4 жыл бұрын

She is so pretty.

@garyhe6267 5 жыл бұрын

5:14 "age at death during the middle ages is left-skewed... cause lots of people died young..." Is "left-skewed" a slip of the tongue? Since more people died young, the median should be to the left of mean, assuming ages lie on the x-axis from 0 to 100, which gives the right-skewed distribution.

@poptimist5566 6 жыл бұрын

Is there going to be a crash course maths? I feel it's weirdly missing, given the large amount of science and other things that rely on a good basic understanding of it and the connected subjects such as discrete maths and algorithmic maths Not sure if this is the best place to ask this though...

@timeaesnyx 6 жыл бұрын

William Walls crash course is produced by pbs. Pbs has another channel called infinite series that deals with math.

@JJ-vh8ex Жыл бұрын

Wouldn't age of death in the middle ages be right skewed? Wouldn't all of the older ages be on the right, and therefor the tail be on the right..?

@Alverant 6 жыл бұрын

That bimodal distribution with the Boston Marathon had two peaks, one for men one for women. It was even labeled on the graph. Oops. Props for the gamers' dice though!

@lucasng4712 6 жыл бұрын

That was not the point

@jayabhadrajayaraju9625 5 жыл бұрын

She reminds me of rudy macunso

@XrollhaX 6 жыл бұрын

That’s harder then the physics one.

@DuranmanX 6 жыл бұрын

Proud to say I could name most Pokemon and countries in the world

@Psychkota Жыл бұрын

I decided I must come here because after 6 hours I have completed a single statistics question.

@jesstheevilone 6 жыл бұрын

Today I learned that male marathon runners = professionals and female marathon runners = amateurs

@joshuamorris8635 4 жыл бұрын

Decent overview, but perhaps too simple.

@DrRonontheInternet 6 жыл бұрын

DFTBA... Q (lol)!

@kobaltsar 6 жыл бұрын

No one is gonna be getting 100% on that name all countries test, hell I've been trying to get there for 2 years and I can only hit about 180/195

@ThePstjtt 6 жыл бұрын

@voltairesarmy6702 6 жыл бұрын

I'm Wondering that too.

@ZamanSiddiqui 6 жыл бұрын

ThePstjtt Don't Forget To Be Asking Questions.

@user-pl1xk5jf4c 6 жыл бұрын

It could have something to do with Lgbtq but I have no clue

@KenKopin 6 жыл бұрын

This is just a guess, but since Q refers to the proportion of population elements that do not have a particular attribute (in this case, Awesomness?) Then DFTBAQ reads Don't Forget To Be Awesome, All of you people who are currently NOT AWESOME. :) Presumably the Already Awesome people didn't forget, and thus don't need the reminder.

@maniam5460 6 жыл бұрын

Ken Kopin that would be way cooler than just Don’t forget to be asking questions which is what she said in the last video

@anamikebour3959 4 жыл бұрын

Someone please explain to me how height is infinite??

@pks171 4 жыл бұрын

It just means that it's continuous. People can be 176cm, 176.1cm, 176.11cm, 176.2cm, 176.223cm, 180cm, 180.5cm, 180.6cm etc. There's just so many values height can take that it's infinite.

@Shubang101 6 жыл бұрын

Crash course anthropology?

@tjdriver7098 6 жыл бұрын

WHOOOHOOO FIRST VIDEO I AM EARLY ON OMG YAY I'm THE 7TH COMMENTER AND 29th LIKER GUYSSS I DID IT

@tyrmyrmidon2846 6 жыл бұрын

No lolly-gagging

@mostafaragab1477 6 жыл бұрын

ترجمه عربى لو سمحتوا

@fatthar4804 6 жыл бұрын

Just ask the bank

@conradmaclean4073 5 жыл бұрын

What does she mean it 'generates random numbers'??? and what does she mean it 'generates the number of leaves on a tree?' does she mean the machine counts the leaves or theoretically generates the leaves? I'm in post grad and this makes no sense

@yakushiji5393 5 жыл бұрын

DFTBAQ

@Destinywin11 5 жыл бұрын

I think this lady in the video looks like Lexi Walker.

@fupopanda 5 жыл бұрын

Good for refreshing your knowledge. But I can imagine this is terrible video for learning the first time.

@rkpetry 6 жыл бұрын

...2 min. vs 4 min. (bimodality) sounds more like frequency-doubling-a nonlinear process with harmonics... there's often more important, extractable, shaping information, analysts ignore as massaging-too-much after tainting by predecisory mode-information-politics...

@arjanweise3848 4 жыл бұрын

The marathon statistics say, male and female, not professional and amateur.

@premiumwaffle516 6 жыл бұрын

Why am I waching this. lol

@EriqireM 6 жыл бұрын

because it is well made.

@kxngpark 6 жыл бұрын

watching informative things without meaning to is how you acquire knowledge that one day you'll say "i have no idea how i know that" about idk if that sentence made sense.