Chi-Square Tests: Crash Course Statistics #29

Today we're going to talk about Chi-Square Tests - which allow us to measure differences in strictly categorical data like hair color, dog breed, or academic degree. We'll cover the three main Chi-Square tests: goodness of fit test, test of independence, and test of homogeneity. And explain how we can use each of these tests to make comparisons.
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[@BobSmith-pl6sm]

Idk why this is so difficult. The math isn't hard, it's just the process and logic that really messes with my brain 😭

[@PranavViswanathan]

Every AP Bio student quaking

[@carsonchiem145]

FACTS

[@kenxiong9856]

IB :)

[@pantasticlaire3966]

IB bio hère, haven’t done this in quite a bit and paper three is in two hours ish

[@Kaseus-lq7cj]

A2 stud here XD

[@Noncyclic]

YES OML

[@amansamad5172]

Bro i feel even dumber after this video wtf

[@annasimone7780]

same, bro

[@JBX07]

I didn't get it either and not getting it made me sad.

[@graceyudha]

same here

[@shaaaaaalalalaaaaaa]

Bro i guess i should just stick to biology crash course. This one flew right of my head

[@gaxperson3258]

This is CrashCourse's 1000th video.

[@mX-vx9kc]

Is it? I wonder..

[@Aa.oeti59]

An easier way to calculate the expectant frequencies is to use the equation (total of column * total of row)/ sample size. So (161 * 479) / 1000 = 77.12. The way they present it is confusing.

[@dandanthedandan7558]

6:58 I had to repeat this part cause I was taken aback by the unexpectedly large number of people who like pineapple on pizza and couldn't focus on what she was saying.

[@Psd863]

Well done Crash Course on uploading your 1000th video! Seemed statistically significany enough to point out :P Thanks for the wealth of learning material you've provided to so many people around the world. Can't wait to see where the next 1000 will take us!

[@nawakalima2410]

I followed you through the explanation and enjoyed it until the point where you determine whether to accept or reject the null hypothesis. It would be nice in future to show what you referred to when comparing the results of your chi-square test to determine whether it is above or below the critical value (i.e a chi-square table)

[@chizpa305]

Today I was precisely looking for a Chi square video explanation and I found this video (uploaded yesterday). We're entuned.

[@marrane87]

Love ur content, im a peruvian physician taking a master in epidemiology , so biostatistics are a smash in our heads, ur videos are so useful!

[@benderbendingrofriguez3300]

who else would like the League of Lemur to be a real game?

[@emeraldemperor2601]

YASSSS

[@ruijietey4014]

I wanna be a fighter lemur

[@Levy957]

My favorite statistics series

[@luiza1321]

I skipped ahead when I saw the league of lemurs bc I thought it was an ad lol

[@garagelifestyle]

bruh. why does she have to be so fast in stringing and saying statements that we have to digest to understand the concept... this is cooked. anxiety says no thanks.

[@financeataglance8840]

Another excellent video! Very well explained on a concept that is difficult for many students. The Chi Square test is used in finance too!

[@learnlearn8230]

Very well explained. thanks for an amazing contribution. Things are really well related and narrated.

[@blunteddful]

Nice. Very helpful. This is exactly the statistical model I'm working with in my thesis.

[@ImaginaryEvil]

This is really useful, and I'm definitely further forward than I was 15 minutes ago - I understand where the chi-square statistic comes from, but I don't get how to determine the P-value from that

[@EmmaToku]

How did you get the expected data?

[@sonja9120]

Thanks Adriene, you are a lifesaver!

[@tedgrove9412]

This is an amazing explanation! Well done!

[@Lime-rr6te]

this video was very helpful and easy to understand, thank you

[@XxxFoxionzxxX]

This was fantastic. Great work.

[@mesplin3]

When I read Wikipedia about statistics, there seems to be some political division between advocates of Bayes theorem and advocates of traditional statistics. Is this division an illusion?

[@y__h]

Oh you meant Bayesians vs Frequentists? It's basically kinda like Mathematicians vs Physicists, or Pi vs Tau.

[@mesplin3]

Right. There is no disagreement on the math, right? They may just the disagree on the interpretation. For example both parties would agree that chi squared distribution is appropriate for this situation, yes?

[@OlleLindestad]

Bayesians and frequentists like to use different methods, but there's also a sort of philosophical divide over how to think about hypotheses and probabilities. I recommend reading some stats blogs if you want to know more. Wikipedia's stats articles can be nigh-on impenetrable, but there are a lot of good and accessible stats bloggers on both sides of the Bayesian/frequentist divide.

[@aimeegardner9736]

I still don't understand what exactly expected data is? Is it just what people expect to happen, or is it data based on previously carried out research?

[@이신우-k4u]

Thank you so much.. Helped me understand chi sq test. So neatly organized too T^T thank you

[@Johnjo85]

League of Lemurs, nice parody of HotS and DotA. ^_^

[@TheDezz91]

Kappa

[@BantamJJ]

where can I download this lemurs games pls

[@lidabaynes600]

It a great video on statistical concept however, the presenter should talk and explain a bot slower! You are too fast to be understood Amazing Lady!

[@Edgelordess]

Leauge of Lemurs lol! XD What class do I choose if I wanna be a spell caster?

[@kenxiong9856]

wouldn't be healer

[@Optimistas777]

woudn't be a tank too

[@TalysAlankil]

I'd play the hell out of League of Lemurs

[@kyrag4295]

One thing about the cat/dog owners. We would have to make sure no cat owner also owns a dog or vice versa, otherwise chi square is not mutually exclusive - there for not valid. Otherwise, love your videos!

[@sidzilpe9391]

Yay 1000th video of the CC series

[@pawtleopard]

Can you guys make an advanced statistics?

[@MartaniPanganSehat]

Thankyou.

[@dylanhritchuk2829]

Where was this video when I took Quantitative Methods last semester 😑

[@TimberWulfIsHere]

you just do quatitative? bruh... my unit has both quantitiative and qualitative methodologies to study....

[@jeronimotamayolopera4834]

HAPPY FESTIVUS.

[@cirusMEDIA]

*Fail to Reject* may not have been the best words to use. (without an explanation )

[@ognjenjosifov126]

Thank you again ❤❤❤❤ ❤

[@AyushSingh-mv8sp]

A survey of 320 families with 5 children each revealed the following distribution: No. of boys 5 4 3 2 1 0 No. of girls 0 1 2 3 4 5 No. of families 14 56 110 88 40 12 Is the result consistent with hypothesis the male and female birth are equally probable?

[@fatihataheya2718]

ANOVA and regression next pls

[@aaronmarks9366]

My favorite statistics documentary series is PBS ANOVA

[@Heavy2deep]

Always a pleasure

[@qqq_Peace]

Brilliant video, thanks!

[@kayak0000]

Ayayay! Box and whiskers plot at the back! *heart*

[@ainmartinez8186]

BS psychology student here 😊🙋

[@bjarbj944]

Best video ever

[@kevinlu2155]

League of Lemurs...it better win game of the year awared

[@KazuichiSoda.]

Now I want to play League of Lemurs XD

[@alex_9504]

Could you do accounting or business?

[@Edgelordess]

Or crash course american politics?

[@janetgarcia6143]

ACCOUNTING YES PLEASE

[@audreyxiao6607]

Love this!

[@leoniduvarov6565]

great video

[@juliannaokike31]

We know what time it is and where we stand don't we.

[@Shermaine2009]

Can I get a link to download League of Lemurs after I’m done with my dissertation? 🥺🥺🥺

[@raiwood77]

Who does this in A Level Biology🙋🏾‍♂️

[@yuno9121]

rai francisco no one

[@iRiShKnIcKs2011]

Just finished A level biology this year, and we did do it 👆

[@yuno9121]

Shahmeer Hamid oh, I didn't know they taught it at a lvl biology. also how hard is a level biology your opinion

[@khbye2411]

Dihybrid crosses hahahaha

[@cboaitey99]

We had to do it for A level geography too 😂

[@preetidipajena6766]

Why in chi square expected frequency for every cell is greater than 5?

[@Jinx-il9jo]

Slytherin and I love pineapple on pizza

[@Voidsworn]

Hundreds of unique lemurs.

[@ViragHegyi-bs2ge]

I was with her pretty much the whole way but then right around minute 9, she completely lost me... Aaaaaaahh!! :(

[@CautionCU]

2:30 League of Lemurs!!!!

[@jestbraine4076]

D

[@mikkelmller-srensen3727]

only more confused.. this makes no sense..

[@EricaFioriGentry]

This was is helpful!!!! Thank you so much!

[@小小帳號]

Why chi-square distribution looks like that weird shape??

[@jacoboribilik3253]

There is not a reason behind its shape. It is just the way it looks like.

[@SyMpHOny893]

I listened to this whole video but I didnt hear anything after the first test... wtf

[@sudeepjoseph69]

corona ke ghayenge hoi? Mer pekashukti goki lema? Koi?

[@milkwithanime]

where can I play League of Lemurs? Asking for a friend ...

[@k1nj3]

Damn so useful

[@BRANDONYERMASH]

Zenilman AP Bio!

[@carsonchiem145]

lmao

[@hek4036]

@ 9:28 i dont get 1.6 . Shouldnt it be 3.4?

[@AmirGTR]

I really appreciate that you guys are making these videos, but I was pretty disappointed in the statistics crash course. First of all I don't recognize any of the variable names on the screen. Using broken words like "Exp" or "Obs" is confusing as hell, in fact in product design it is considered an obsolete practice. Just use designated variable names like x and n. I appreciate the real life examples but stick to one example, and expand on it. Establishing an entirely new context in your mind every 2 minutes is not easy when you're trying to pay attention to the lecture. And you really have to explain the connection for each example, not just move on and give 3 more before the first one gets through. Her pace and way of talking really throws me off. I dunno if she doesn't have enough energy and she seems to assume I know everything, or if she's being drowned in distractions. She doesn't solve any problem examples and uses too many words to explain an otherwise simple concept. And what is that annoying noise when the text is being displayed? So distracting. I really preferred your Psychology crash course much better. Sorry 🤷🏻‍♂️

[@jeffreyosiwalajr3161]

Honestly these videos do move really fast. In my opinion you have to be quite familiar with statistics to get a benefit from the videos in just one watch. They're very wordy, and fast.

[@carrymeorgg8512]

League of Lemurs made me want to play league of legends instead of studying. Guess I'll watch the video tomorrow xD

[@MW-bk2nc]

she has nice eyes

[@juliannaokike31]

No more Maggie

[@Curry_Ramen]

How did you get P as 0.3 I didn't get it

[@XxxFoxionzxxX]

EnigmaticSkygazer check the value of chi squared (3.9) and look on tables with df=3

[@CatCamryn]

Damn no McNemar’s Test huh?

[@sudeepjoseph69]

Chukte lamakshuk fama lo ki he? Ram chuckte luky tomchik ki he?

[@CatCamryn]

​@@sudeepjoseph69 What?? Idk the language you're speaking dude.

[@sudeepjoseph69]

@@CatCamryn HAHAHA. Loke gayinga! Mer chuckte ki he lo! HAHAHA

[@CatCamryn]

@@sudeepjoseph69 ah yes loke gayinga indeed.

[@owenmarks2060]

huh?

[@ScarrVett]

Haaahahahha League of Lemurs hahahahha

[@grainfrizz]

If chi-square came out this late in the series, then there might be something wrong with the curriculum I attended to in college. Chi-square was taught to us in the beginning of the course (just few days into it)

[@ianwells7309]

Yo

[@ianwells7309]

Hi

[@yuno9121]

bye

[@rosschad8448]

Who else can only think of John Green when the intro music plays?

[@dannyg1056]

Too fast. Edited to take out the pauses for thought. I need those pauses. Not stop chatter is too mind boggling. Thank you, anyways.

[@JulieBall-dg2ci]

The graphics are so distracting.

[@yuno9121]

*league of lemurs!!*

[@AVEdrums]

This came to late, had my exam on monday

[@yuno9121]

AVE drums lol what exam

[@Mist_R]

league of lemurs LMAO

[@vampayor]

All the people who said they love pineapple on pizza are probably trolling, thus making it inaccurate data.

[@juliannaokike31]

Once someone do me dirty you not coming back from that.

[@rebbekahalcazar3179]

It's so hard to follow these videos. She talks so fast and I can't follow.

[@styxnexus]

Try 0.75x playback speed.

[@sudeepjoseph69]

Melakai ur pekshamtu? Lokei yakam chupki he?

[@TadanoCandy]

why am I not surprised that the two highest houses were Hufflepuff and Ravenclaw xD I'm a Hufflepuff. I guess lots of nerds are affable or intelligent.

[@lukeleighton3872]

First.

[@arneshsharma5247]

Luke Leighton nope I was a sec earlier

[@lukeleighton3872]

Nooooooo! 😢

[@arneshsharma5247]

😂

[@nottellingnottelling3533]

Fifth

[@taiipotatoie]

League of lemurs lol

[@gurpreetbhamra9752]

Taii potatoie 🤣🤣🤣

[@lambikialubino6017]

please try to stop talking too much and give more necessary info

[@saipranavguduru9910]

2000th view

[@arneshsharma5247]

First

[@coconut7812]

You lost me every where!!! Delete

[@henrys2934]

filth

[@ice9743]

I do not believe that there would be more people that like pineapple on pizza than not no matter what survey it is. Even if it's at a pineapple pizza convention it should still be the minority. This data is false!

[@pyrophred]

51% of nerdfighters are wrong about pineapple on pizza... Also I may be a Slytherin