Conditional Probabilities, Clearly Explained!!!

Рет қаралды 188,165

Күн бұрын

One the most fundamental concepts in Probability, Statistics and Bayesian Statistics is Conditional Probability. In this StatQuest, we walk you through what Conditional Probabilities are and how to calculate them using raw data as well as unconditional probabilities. BAM!!!
For a complete index of all the StatQuest videos, check out:
statquest.org/video-index/
If you'd like to support StatQuest, please consider...
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KZfaq Membership: / @statquest
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0:00 Awesome song and introduction
1:11 Filling in a contingency table
4:45 Calculating conditional probabilities from counts
8:00 Calculating conditional probabilities from unconditional probabilities.
#StatQuest #Probability #Bayesian

Пікірлер: 368

@statquest 2 жыл бұрын

NOTE: Conditional probabilities can be written two ways: a "long" version and a "short" version. In this video I use the long version (because it's easier for me to read)... P(A and B | B) = P(A and B)/P(B) ...however, the short version is commonly used... P(A | B) = P(A and B)/P(B) Both mean the same thing, in other words: P(A and B | B) = P(A | B). The short version implies the "and B" part. Support StatQuest by buying my book The StatQuest Illustrated Guide to Machine Learning or a Study Guide or Merch!!! statquest.org/statquest-store/

@exploringdiversity572 2 жыл бұрын

Your version is much easier for non-statisticians like me :)

@statquest 2 жыл бұрын

@@exploringdiversity572 bam!

@chandrashekar316 2 ай бұрын

omg this cleared up so much confusion i had from reading my text book where they were using the shorthand

@pomegranate8593 2 жыл бұрын

I love how I need a video that seems designed for 7 year olds to understand my uni course. Great vid thanks

@statquest 2 жыл бұрын

Glad it was helpful!

@BulbasaurLeaves Жыл бұрын

I like the style. It's fun and nostalgic

@TheRedCubeYT 29 күн бұрын

this is secondary school level maths

@asrao3788 15 күн бұрын

In India due to competition for engineering entrance exam teacher majorly focus on question types rather than concept in depth. Im glad there is a place where people learn for fun not just for competition, also appreiciate teachers like you who can turn subjects into magic. Keep up the good work! From now on I'm permanent on this channel. You are the best!

@statquest 15 күн бұрын

Thank you very much!

@shinej11 2 жыл бұрын

I always thought I was incapable of learning math, but it had always intrigued me. I just discovered what was missing; a good teacher. Thank you very much.

@statquest 2 жыл бұрын

bam!

@PastryDonut Жыл бұрын

I'm in the same boat as you man, love this channel

@jacob.9664 Ай бұрын

Soda and Candy > Mechanical engineering degree. Thank you it was very helpful!

@statquest Ай бұрын

BAM! :)

@pkmath12345 2 жыл бұрын

Very nice video for sure. Conditional prob is one of the topics students feel the most difficulty when they start studying for stat! Great job!

@statquest 2 жыл бұрын

Thank you! :)

@HardikBhakhar 23 күн бұрын

Never thought that to understand conditional probabilities is this easy … thanks prof 🎯

@statquest 23 күн бұрын

bam! :)

@mikejohns1347 2 жыл бұрын

I "stumbled" upon the contingency table method many years ago when trying teach myself the basics of probability. This approach is really the only approach for developing a solid understanding of conditional probability, as well as joint and marginal probability. I've never seen anyone present it this way and I'm so glad to see it here! Just more evidence that Josh Starmer is an absolute master instructor.

@statquest 2 жыл бұрын

BAM! Thank you very much! :)

@endahfajarwati8336 2 жыл бұрын

you know, me too.

@Ash-bc8vw 2 жыл бұрын

Hey this table reminds me of confusion matrix from a ML classification problem

@turtle3341 2 жыл бұрын

this is how i wish people taught stuff, i really hope these ways of learning statistics get the recognition they deserve! please keep it up !!!!

@statquest 2 жыл бұрын

Thank you!

@azinkhodadadi7912 Жыл бұрын

I should of paid you instead of my useless lecturer at university! This is so much more useful thank you!

@statquest Жыл бұрын

Glad I could help!

@baqirhusain5652 2 жыл бұрын

You are a GOD of simple explanations

@statquest 2 жыл бұрын

Thanks!

@phuctran4679 2 жыл бұрын

Thank you Josh & the team. I'm so grateful I've found your channel. You make me truly love statistics!

@statquest 2 жыл бұрын

Glad you enjoy it!

@rejithmadhavan5735 2 жыл бұрын

Logical explanation, precision and genuineness - your way of teaching exemplifies these essential qualities. Thanks so much Josh for these great lessons. Invaluable effort!

@statquest 2 жыл бұрын

Wow, thank you!

@jacktaylor1516 2 жыл бұрын

This is one of the best explanations of absolutely anything I've ever seen and heard. Well done. Subscribed.

@statquest 2 жыл бұрын

Awesome, thank you!

@leandroimail 2 жыл бұрын

I love these classes. They are so easy to understand. Thks you for sharing with us!

@statquest 2 жыл бұрын

Thank you very much! :)

@talentlancer1358 Ай бұрын

Thank you so much! This is the best video on conditional probability on internet.

@statquest Ай бұрын

Thank you!

@colinirvine757 2 жыл бұрын

Great job Josh!!!!! This is such a clear and precisely laid out video perfect for my students.

@statquest 2 жыл бұрын

bam!

@dizetoot 2 жыл бұрын

THANK YOU! I've really been struggling to get an intuitive understanding of conditional probability and this has helped so much!

@statquest 2 жыл бұрын

Glad it helped!

@fatimajahara4871 Жыл бұрын

I love how the videos comprehend complex topics with easy-to-understand explanations. Thanks for all your effort :)

@statquest Жыл бұрын

You're very welcome!

@AndrywMarques 2 жыл бұрын

Great video! I never saw the "long version" to write conditional probabilities before but it's better to understand. Very intuitive!

@statquest 2 жыл бұрын

Yes, I like it more, too.

@Regular.Biceps Жыл бұрын

Exceptional explanation... I'm Completely in love with your teaching style

@statquest Жыл бұрын

Thank you!

@arpitkakkar2780 2 жыл бұрын

Awesome. I always come here to get my doubts clear. Love the way you teach. Lots of BAM!!!

@statquest 2 жыл бұрын

Thanks!

@Florithepenguin 2 ай бұрын

Struggled with this topic literally for years! You solved my problem within just 10 min.! 🎉

@statquest 2 ай бұрын

Bam! :)

@anthonyrinna1305 2 ай бұрын

First, I'll admit I had "Do you love orange soda?" from Keenan and Kel in the back of my mind. That said, this video has been immensely helpful, thank you!

@statquest 2 ай бұрын

@ivlivs.c3666 Жыл бұрын

Incredibly well-explained. Thank you!

@statquest Жыл бұрын

Thank you! :)

@vavy5652 Жыл бұрын

You are literally saving me from my statistics exam! Thank you so much, your explanations are brilliant and you are really making me focus with your simple and funny ways. Thank you again!

@statquest Жыл бұрын

Good luck! :)

@Oliver-cn5xx 2 жыл бұрын

Hi Josh, I am a long time fan of your channel and all of the shameless self-promotion has guilted me into buying one of your study guides (LDA). They seem great, a nice supplement to your videos. Though I think you would benefit greatly from stripping down the ordering process, I mean for online purchases almost noone asks for complete addresses, phone numbers and names anymore. I fought very hard with myself to finish it and parting with that information, and I succeeded simply because of being so grateful for the videos you provide. You'd probably sell a lot more of these if you just ask for an email. Like most. Cheers

@statquest 2 жыл бұрын

Thanks for the advice! I'll see what I can do to simplify the ordering process.

@onurkrmz9206 2 жыл бұрын

Today I discovered your channel and it is truly a gem. As a EEE student who tries to make sense of subject of probability and neural network stuff, I believe I will benefit a lot from your work and be thankful for rest of my life. Especially statistics is challenging as things get messy a lot and scary/unintuitive equations with confusing notations start to appear. I did not look at all of your videos yet, but I hope that you did statistics less scary for those like me. My best regards

@statquest 2 жыл бұрын

Awesome! Here's a page that lists all of my videos (and playlists etc): statquest.org/video-index/

@jacktrimboli2857 2 жыл бұрын

I get a dopamine rush every time this man says bam

@statquest 2 жыл бұрын

bam!

@amribrahim7850 2 жыл бұрын

Awesome explanation. Thanks to you and Triple Bam members

@statquest 2 жыл бұрын

Glad you liked it! BAM! :)

@Nakameguro97 2 жыл бұрын

Thank you SO MUCH for clarifying that AB = A and B, when A and B are events. I get confused because XY is literally multiplication when X and Y are random variables. It can be doubly confusing because both events and random variables (even though they are different types) can be passed into P(), the probability function. Function overloading is a thing in computer programming, but I’m shocked to see it in math. Also, the implied A and B in P(A | B) is a lifesaver, many times over. BTW, understanding the tables in this video is pivotal in grasping marginal distributions, Baye’s Theorem, and joint probability distributions - it feels like I’m getting the other three concepts for free!

@statquest 2 жыл бұрын

Triple bam!!! :)

@tyt03538 2 жыл бұрын

This is the best video explaining conditional probability. Hands down.

@statquest 2 жыл бұрын

Thanks!

@ShashwatAgarwal007 2 жыл бұрын

Happy Guru Purnima Sir, So blessed that this channel exists. ❤️🙏

@statquest 2 жыл бұрын

Thank you! And thank you for supporting StatQuest! BAM! :)

@tomr03status99 2 жыл бұрын

❤️❤️

@jerryquid4057 Жыл бұрын

You're incredible. You make everything seem so easy

@statquest Жыл бұрын

Wow, thank you!

@swarnachoppella388 2 жыл бұрын

Thank you! Great content always🤩

@statquest 2 жыл бұрын

My pleasure!

@buihung3704 6 ай бұрын

A 6 years old can understand this. That's genius

@statquest 6 ай бұрын

Thanks!

@yujan9103 Жыл бұрын

Well explained. Bit long but makes the concept clear as possible. A big THANK YOU Josh.

@statquest Жыл бұрын

Thanks!

@between_the_lines6173 8 ай бұрын

You're the statistics buddha! The analogies and the calming voice!

@statquest 8 ай бұрын

Thanks!

@sanjeevsingh-zz2hg Жыл бұрын

Your way of teaching ! Bam!

@statquest Жыл бұрын

Thanks!

@rishikeshpillay 2 жыл бұрын

Thanks for this explanation.....It really help me to grasp this topic....

@statquest 2 жыл бұрын

Bam!

@uvofsam 2 жыл бұрын

Bam!! , what a bam person to explain everything about statistics so bamly!!

@statquest 2 жыл бұрын

Thanks!

@NoahElRhandour 2 жыл бұрын

Bamks!

@vinodliyanage4128 2 жыл бұрын

Best explanation ever. Thank you! ❤️

@statquest 2 жыл бұрын

Thank you! :)

@user-lc4nv3qy4i 7 ай бұрын

This was amazing and fun. Thank you!

@statquest 7 ай бұрын

Glad you enjoyed it!

@dyles1832 2 жыл бұрын

The people demand a Montecarlo Simulations StatQuest!!!

@justinwhite2725 2 жыл бұрын

That would be nice.

@statquest 2 жыл бұрын

I'll keep that in mind. We may get to something like it when I cover bayesian statistics.

@tomr03status99 2 жыл бұрын

That could be nice

@gabrielasantana3809 2 жыл бұрын

And BAM! I subscribed….such a clear explanation

@statquest 2 жыл бұрын

Awesome, thank you!

@zaf3153 Жыл бұрын

Super easy ti understand! Thanks alot

@statquest Жыл бұрын

Glad it helped!

@BARAKABLESSING Жыл бұрын

This helped understand c prob. I am taking a mandatory into to stat class with no math experience and passion. Thanks

@statquest Жыл бұрын

Good luck!

@KweenFlorp 8 күн бұрын

i love you this actually helped so much

@statquest 8 күн бұрын

Thanks!

@ceseb23 2 жыл бұрын

Great video, perfect explanation, marvelous song, as always :D I would love to see a video about Generalized Linear Models( other than logistic).

@statquest 2 жыл бұрын

Thanks and I'll keep that topic in mind.

@tomr03status99 2 жыл бұрын

👍👍👍

@pratyushkashyap849 Жыл бұрын

Incredible lecture!! Bamm😀

@statquest Жыл бұрын

Thank you!

@ramprakash7872 2 жыл бұрын

Conditional probability : Decoded. BAM !!! Tbh Some of your videos ( Very few actually. For example p-value 😁) were not very clear to me ( Well that's just me ! ) in the first instance but I digested through them somehow. But with little study & focus or just give a break for a while, the 2nd or 3rd look at your video makes the concept super clear to me and I don't need to look elsewhere. Thanks for making such videos and making statistics/probability easier.

@statquest 2 жыл бұрын

I'm glad you are able to understand the concepts.

@faiazrummankhan5589 2 жыл бұрын

This channel is the bible of " Making 'Understanding Statistics' Easy !"

@statquest 2 жыл бұрын

bam! :)

@shamsulazhar 2 жыл бұрын

Finally, I understand this. BAM!!!!

@statquest 2 жыл бұрын

Bam!

@LukaszWiklendt 2 жыл бұрын

It's interesting notation that you keep the superfluous condition on the left side of the pipe. I.e. using p(c=0 and s=1 | s=1) instead of p(c=0 | s=1). Do you find students understand it better this way?

@statquest 2 жыл бұрын

Yes. To me it is much clearer.

@anashaat95 Жыл бұрын

Thanks a lot. Clearly explained as you stated.

@statquest Жыл бұрын

Thank you!

@AbcdAbcd-ol5hn 2 жыл бұрын

😭😭😭😭thanks a lot😭😭😭god bless you, u are doing a noble job, may you get all the riches, love and happiness in the world

@statquest 2 жыл бұрын

Thank you very much! :)

@dhendroid2373 2 жыл бұрын

This is how every tutorial should be!

@statquest 2 жыл бұрын

Thanks!

@surendrabarsode8959 2 жыл бұрын

Very well explained as usual!! BTW, do you have any plans for making videos on stochastic calculus topics like Brownian motion, Ito integral, martingale measures etc. If so, I am looking forward to them.

@statquest 2 жыл бұрын

I'll keep those topics in mind.

@tomr03status99 2 жыл бұрын

👍👍👍👍

@sillyfarmerbilly8872 2 жыл бұрын

"statsquatch" I love it 😂 Also I guess I never put together that you could use the probabilities to calculate conditional probabilies, super helpful

@statquest 2 жыл бұрын

BAM! :)

@durgeshkshirsagar116 2 жыл бұрын

Wow. Great explanation with nice song ❤️❤️

@statquest 2 жыл бұрын

Thanks a lot 😊!

@durgeshkshirsagar116 2 жыл бұрын

@@statquest welcome sir 🙏🏻

@sigmakings7285 8 ай бұрын

That's a great one.thank you😊

@statquest 8 ай бұрын

Glad you liked it!

@josevaldes7493 2 жыл бұрын

amazing googleplex BAM! Man you did it again. BRAVO

@statquest 2 жыл бұрын

Wow, thanks!

@shahf13 2 жыл бұрын

Great job josh you are my favorite teacher !! , can you think about making a video about Multicollinearity? bam

@statquest 2 жыл бұрын

I'll keep that in mind.

@RaceyBeats 2 жыл бұрын

So bloody good!

@statquest 2 жыл бұрын

Thanks!

@avrilduck8326 25 күн бұрын

After 4:40, I cried "that's enough" because it was relentless!!

@statquest 25 күн бұрын

bam

@qwerty11111122 2 жыл бұрын

Hi Josh! I've been working with DEseq2 a lot. Is dispersion shrinkage on your TODO list for statquest? I realize it's a little more of a niche topic for bioinformatics than broadly applicable tho

@statquest 2 жыл бұрын

I'll keep it in mind.

@kayhankashi9970 6 ай бұрын

SUPERB explanation... BAAAM !!!!!

@statquest 6 ай бұрын

Thanks!

@ahmadatta66 2 жыл бұрын

"I hate using abbreviations" And I love you for that

@statquest 2 жыл бұрын

bam!

@simonroques8579 2 жыл бұрын

Excellent video..again ! So good to be hit by the triple bam !!! 😁

@statquest 2 жыл бұрын

Hooray! :)

@sleepydev4700 2 жыл бұрын

Hundred Bam!! Great explanation as always Could you put the playlist link in the description, it will help us a lot, thanks.

@statquest 2 жыл бұрын

Which playlist are you asking about?

@Darkev77 2 жыл бұрын

This might sound like a silly question but, shouldn’t one expect that P(A | ~A) = 0, and vice-versa? However this conditional notation doesn’t encompass that

@statquest 2 жыл бұрын

Actually, it does. What you are asking is "The probability that someone loves candy AND does not love candy given that we know that they love candy". This results in the equation p(loves candy & does not love candy) / p(loves candy) = 0 / (6/14) = 0.

@Darkev77 2 жыл бұрын

@@statquest thanks a lot prof for your clarifications!

@sudhamjayanthi Жыл бұрын

thank you, uncle bam!

@statquest Жыл бұрын

My pleasure!

@joshuaperling2985 2 жыл бұрын

amazing! the best!!

@statquest 2 жыл бұрын

Thank you! :)

@kekahazra9769 3 ай бұрын

Bam! I like the way you teach.....keep up!....Bam Bam!😅

@statquest 3 ай бұрын

Thank you very much! BAM! :)

@SarahFeng92 8 ай бұрын

Your channel is amazing, I wish I had discovered it earlier! Would you ever consider making the slides available for sale? I would absolutely buy them.

@statquest 8 ай бұрын

I have some of them for sale here: statquest.org/statquest-store/

@EngRiadAlmadani 2 жыл бұрын

BAMMM!!!! Great work Can you make video about bayesian classifier because it's depending on conditional probability

@statquest 2 жыл бұрын

I've already done that. Here's the link: kzfaq.info/get/bejne/hZh8ZbinntbIdHU.html

@janiceoou 2 жыл бұрын

I was looking for sth like this recently, thanks for somehow read my mind XD (I guess some kinda probability?? BAM!

@statquest 2 жыл бұрын

BAM! :)

@yonatanaquinteror2989 2 жыл бұрын

Awesome! BAM!!!

@statquest 2 жыл бұрын

@kensarmoreto1863 Жыл бұрын

although that i calculate conditional probability during college, i cannot get the concept of it leaving a gap in my stat knowledge... i stumbled in your video and i have a basic understanding about it. im just need a more examples regarding conditional probability to fully master this concept... Thanks Josh for your videos and hoping for more topics about stats and data analysis.

@statquest Жыл бұрын

I'm glad my video was helpful! :)

@fabianarodriguez. Жыл бұрын

I GET IT NOW THANK U SO MUCH

@statquest Жыл бұрын

bam! :)

@jbetanco7733 Жыл бұрын

good job

@statquest Жыл бұрын

Thanks!

@sumonmiah8957 7 ай бұрын

Great! Which software have you used to make this video(especially animation)?

@statquest 7 ай бұрын

I give away all of my secrets in this video: kzfaq.info/get/bejne/mdh8i614kqulmJ8.html

@markobe08 2 жыл бұрын

Josh is the best

@statquest 2 жыл бұрын

Thanks!

@tomr03status99 2 жыл бұрын

Yeh!

@angelgamboa5902 2 жыл бұрын

amazing!!!!

@statquest 2 жыл бұрын

Thanks!

@piruthuviraj5903 2 жыл бұрын

Thank you so much...Now I cleared. 😁🥰🥰

@statquest 2 жыл бұрын

bam!

@micahdesign6657 2 жыл бұрын

best video ever !

@statquest 2 жыл бұрын

@shangauri 2 жыл бұрын

Good one Josh. Any plans of making videos on "Time series Models" ?

@statquest 2 жыл бұрын

One day! :)

@catherinele8417 2 жыл бұрын

Hi ! I really like yours graphics and pictures ! What tool do you use ?

@statquest 2 жыл бұрын

Keynote.

@catherinele8417 2 жыл бұрын

@@statquest thank you :)

@RajSARAF495 10 ай бұрын

Beautiful ❤

@statquest 10 ай бұрын

Thank you! :)

@graningfire1776 Ай бұрын

Quadra BAMMMM ! ITS now clearly cleared in my mind

@statquest Ай бұрын

It's not clear? What time point, minutes and seconds, was confusing?

@graningfire1776 Ай бұрын

@@statquest sorry sir , I wish to write now but due to my mistake it become not .

@sampathkumar3405 2 жыл бұрын

Josh , Please start a series for mathematics concepts for machine learning. Such as probability, linear algebra, statistics, calculus etc.. It'll great help for us.

@statquest 2 жыл бұрын

I have a bunch of statistics videos here: statquest.org/video-index/

@jackfrost8969 Ай бұрын

Excellent excellent excellent

@statquest Ай бұрын

Many many thanks!

@levine1886 2 жыл бұрын

Any chance you could post a video on when to run regular linear regression vs. time series ARIMA?

@statquest 2 жыл бұрын

I'll keep that in mind.

@sumailsumailov1572 2 жыл бұрын

So cool!

@statquest 2 жыл бұрын

bam!

@udhayveersingh2000 9 ай бұрын

@@statquest💥

@fabriciomagalhaessena2289 Жыл бұрын

Thank you so much for this video! It saves my life hahaha

@statquest Жыл бұрын

Thanks!

@CW-vl9zd 2 ай бұрын

Good video that cleared up a lot of my questions. Only thing I'm confused now tho is 9:20 let's say we are given all the probabilities. How do I know if a probability is p(not love c and loves s | loves s) or p(loves s | not love c and loves s)? Confused because we know both the numerator and denominator. Thanks

@statquest 2 ай бұрын

Well, the second one, p(loves s | not love c and loves s), really doesn't make sense to calculate at all. This is because the conditional part, "not love c and loves s" is only a subset of "loves s", and thus, the conditional part does not give us any useful information about the larger "loves s" population.

@CW-vl9zd 2 ай бұрын

@@statquest Thank you!