Backpropagation calculus | Chapter 4, Deep learning

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Written/interactive form of this series: www.3blue1brown.com/topics/ne...
This one is a bit more symbol-heavy, and that's actually the point. The goal here is to represent in somewhat more formal terms the intuition for how backpropagation works in part 3 of the series, hopefully providing some connection between that video and other texts/code that you come across later.
For more on backpropagation:
neuralnetworksanddeeplearning....
github.com/mnielsen/neural-ne...
colah.github.io/posts/2015-08-...
Music by Vincent Rubinetti:
vincerubinetti.bandcamp.com/a...
Thanks to these viewers for their contributions to translations
Hebrew: Omer Tuchfeld
------------------
Video timeline
0:00 - Introduction
0:38 - The Chain Rule in networks
3:56 - Computing relevant derivatives
4:45 - What do the derivatives mean?
5:39 - Sensitivity to weights/biases
6:42 - Layers with additional neurons
9:13 - Recap
------------------
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Пікірлер: 2 000

  • @3blue1brown
    @3blue1brown6 жыл бұрын

    Two things worth adding here: 1) In other resources and in implementations, you'd typically see these formulas in some more compact vectorized form, which carries with it the extra mental burden to parse the Hadamard product and to think through why the transpose of the weight matrix is used, but the underlying substance is all the same. 2) Backpropagation is really one instance of a more general technique called "reverse mode differentiation" to compute derivatives of functions represented in some kind of directed graph form.

  • @iamunknownperiod3355

    @iamunknownperiod3355

    6 жыл бұрын

    You should probably change the thumbnail. The snapshot of the variables with indices (which I didn't know were indices at the time) and subscripts almost deterred me from watching this although it really wasn't that complicated.

  • @TalathRhunen

    @TalathRhunen

    6 жыл бұрын

    I will probably be a TA for a lecture course on Deep Neural Networks again next semester and I will recommend this series to the students (we did it in a very math-heavy way this year and it was a bit too much for some of them, even though its a lecture for master students)

  • @sebaitor

    @sebaitor

    6 жыл бұрын

    I was hoping you'd explain in either of these 2 vids on backprop why the hadamard product and transposing are used, what a waste :(

  • @polychats5990

    @polychats5990

    6 жыл бұрын

    Amazing video, I think you did a really good job of making it as easy to understand as possible while also not simplifying things too much.

  • @bgoggin88

    @bgoggin88

    6 жыл бұрын

    Sirius Black what you could do is download the r package "deepnet" and poke around at the source code. Its written in base r so you can follow it around. This is how I learned, and IMHO the best way to learn.

  • @thomasclark8922
    @thomasclark8922 Жыл бұрын

    This series was my first introduction to Machine Learning 3 years ago. I now work full-time as an AIML Scientist, my life is forever changed. Thank you.

  • @envadeh

    @envadeh

    Жыл бұрын

    how hard was it? I am tryna code my own neural network from scratch, there's so little resources for that it seems. and how do I even make myself unique?

  • @thomasclark8922

    @thomasclark8922

    Жыл бұрын

    ​@@envadeh Learn everything, use the feynman technique; if you can't explain how a machine learns to someone who knows nothing about it, keep filling in the gaps. Formal education is great, but honestly more of a waste of time than not. Teach yourself, learn how to learn, and then keep learning. I audited Andrew Ng's Deep Learning Specialization from Coursera, had some formal education, and self taught myself everything I could get my hands on, from theory to application, the underlying math to the practical programming. Understand the importance of data, DATA IS KING. Watch Interviews with industry leaders, understand the big turning points and continued development within the last two decades of AIML (you'll figure out what they are with time). It takes 10,000 hours to become an expert, I'm about 4,500 in, but all it took was a little bit of work every single day. Make learning a habit. Trust yourself, believe in your ability to become who you want to be. "It doesn't matter if your read two research papers in a week, what matters is if you read two research papers a week for a year, now you've read 100 papers" - Andrew Ng (Don't 'read' research papers, watch synopsis! Smarter not harder! There's so much free information, you could probably use a GPT model to teach you what you don't know!) Goodluck, and I believe in you! :)

  • @nczioox1116

    @nczioox1116

    Жыл бұрын

    Did you need a CS or math degree to get into the field?

  • @thomasclark8922

    @thomasclark8922

    Жыл бұрын

    @@nczioox1116 "Need" is a strong word, it just depends on what kind of work you want to do/who your employer is; people used to go to college because that was the only place you could learn these difficult subjects, but now it's just an archaic way of putting you in debt since you can learn these things online for free UNLESS you want to work for an employer where you need the degree to be recognized. If you are self-motivated and can teach yourself these subjects, seriously consider your options before assuming that spending 4 years of your life and 100k+ is necessary. I have an Electrical Engineering degree, but out of the 40+ classes I had to take for it, only 2 had any sort of impact on my daily job now. It all depends on the context. Goodluck, and I believe in you! :)

  • @nczioox1116

    @nczioox1116

    Жыл бұрын

    @@thomasclark8922 Thank you! I have a mechanical engineering degree. I'm in the process of self teaching myself machine learning concepts and doing some projects. Lots of job postings I've seen in the field seem to require a bachelors or masters in CS, math, or neuroscience. Of course these seem to be for larger companies so maybe smaller companies might take a more holistic approach

  • @kslm2687
    @kslm26876 жыл бұрын

    “The definition of genius is taking the complex and making it simple.” - Albert Einstein You are genius.

  • @jean-francoiskener6036

    @jean-francoiskener6036

    4 жыл бұрын

    I thought he said "You don't understand something well until you can explain it in a simple way"

  • @fractal5764

    @fractal5764

    4 жыл бұрын

    That's not the definition of genius

  • @ericayllon7497

    @ericayllon7497

    4 жыл бұрын

    @@jean-francoiskener6036 yes, it is a quote that appeared in this youtube channel

  • @Djorgal

    @Djorgal

    4 жыл бұрын

    "More quotes are attributed to me than I could possibly have said during my entire life." - Albert Einstein

  • @shawnjames3242

    @shawnjames3242

    4 жыл бұрын

    @@Djorgal Did he actually say that? \

  • @cineblazer
    @cineblazer2 жыл бұрын

    Dear Grant, A year ago, I decided I wanted to learn Machine Learning and how to use it to make cool stuff. I was struggling with some of the concepts, so I went to KZread and re-discovered this series on your channel. Out of all the courses I've tried and all the hours of other content I've sat through, your videos stand out like a ray of sunshine. I just got my first full-time job as a Machine Learning Engineer, and I can confidently say it would never have happened without this series. Your channel may have affected the course of my life more than almost any other. Thanks for all your hard work!

  • @maruferieldelcarmen9573

    @maruferieldelcarmen9573

    2 жыл бұрын

    You could say that this channel had the largest nudge to your activation value

  • @cineblazer

    @cineblazer

    2 жыл бұрын

    @@maruferieldelcarmen9573 The partial derivative of Grant's videos with respect to my career is off the charts!

  • @souls.7033

    @souls.7033

    2 жыл бұрын

    @@maruferieldelcarmen9573 get out 😂

  • @souls.7033

    @souls.7033

    2 жыл бұрын

    @@cineblazer also i just saw your comment 11months ago, it's amazing to see your development! keep it up!!!

  • @khai7151

    @khai7151

    2 жыл бұрын

    Congrats on your job. I was wondering, when you finished Andrew Ng’s ML course, what additional steps and how long did you have to take to become a full fledge ML engineer? Thanks in advance

  • @noahkupinsky1418
    @noahkupinsky14184 жыл бұрын

    Hey for all of you getting discouraged because you don’t understand this - that was me last year. I went and taught myself derivatives and came back to try again and suddenly I understand everything. It’s such an amazing feeling to see that kind of work pay off. Don’t give up kiddos

  • @kg3217

    @kg3217

    2 жыл бұрын

    Thanks for the nice words 🙂

  • @angelbythewings

    @angelbythewings

    2 жыл бұрын

    studied this 3 years ago in college and it all makes sense to me now

  • @xbutterguy4x

    @xbutterguy4x

    2 жыл бұрын

    Yup. I tried to watch this series a year ago and make my own neural network which turned out to be disappointing. A semester into college and some passion for calculus is all it took for me to mostly understand this series!

  • @sukhresswarun

    @sukhresswarun

    2 жыл бұрын

    Same here man I seen this video a year ago But now only i understand fully Keep commenting

  • @oskarwallberg4566

    @oskarwallberg4566

    2 жыл бұрын

    I would say it’s recommended to have read calculus 2 (for partial derivatives and the Jacobian) and linear algebra (for matrix and vector multiplication). Otherwise, just looking up mentioned things is also fine. But it might take time to build up intuition for the math.

  • @hiqwertyhi
    @hiqwertyhi6 жыл бұрын

    It's not that no-one else makes top-notch math/cs videos, it's that this guy makes it CLICK.

  • @ravenn2631

    @ravenn2631

    5 жыл бұрын

    hiqwertyhi It rivals even the website BetterExplained. People like this teach me how to teach.

  • @vgdevi5167

    @vgdevi5167

    Жыл бұрын

    Hello, I'm impressed by the way he explained this topic too, but I'm looking for more such great quality resources, youtube channels, books on deep learning, and also math and comp science in general, what do you recommend?

  • @PhilippeCarphin
    @PhilippeCarphin6 жыл бұрын

    This series is insanely good. As a teacher, I feel like Salieri watching Mozart play and being like "It's so beautiful, how is he so good!"

  • @stanislawgalas

    @stanislawgalas

    5 жыл бұрын

    As a former mathematician I feel the same way :).

  • @hansdieter9911

    @hansdieter9911

    4 жыл бұрын

    I like this analogy.

  • @sashwatdas5482

    @sashwatdas5482

    4 жыл бұрын

    This is the first time I have ever liked a comment bc I could not agree more.

  • @seppl5372

    @seppl5372

    3 жыл бұрын

    @Stanisław Galas I don't get why we want the devirative of c in respect to w^L. can you explain pls? It isn't a division right?

  • @alonsorobots

    @alonsorobots

    3 жыл бұрын

    Too many notes, I do not understand!!

  • @Mrrajender2801
    @Mrrajender28014 жыл бұрын

    Many guys claim to know. Some guys actually know. But only one guy actually knows and can explain to his grandma as well with very beautiful animations. You are that ONE !!!

  • @Seff2

    @Seff2

    3 жыл бұрын

    I think my grandma would understand ;D Maybe on a very very high abstract level.

  • @puppergump4117

    @puppergump4117

    2 жыл бұрын

    @@Seff2 Python grandma

  • @hutc22222222
    @hutc22222222 Жыл бұрын

    Your work of making high levels of math accessible to anyone wishing to learn a variety of new topics is not obvious to me. You succeed to explain everything so clearly, making me want to start learning maths again, reminding me of and introducing me to beautiful aspects of math, and you deserve more than a 'thank you' :)

  • @suharsh96
    @suharsh966 жыл бұрын

    This is the longest 10 minute video I have ever watched. Literally took me half an hour, but the feeling of the idea behind this completely settling in , makes it totally worth it!

  • @phil.4688

    @phil.4688

    4 жыл бұрын

    I think it's easier if you take the time to re-write all of it yourself, on a scratchpad, work through writing the formulas etc. Then you can play with these objects in your mind more fluently. It takes a longer time initially but I feel you get more out of it. And that's a good way to begin "translating" into vector algebra by taking "simple" papers on DL (haven't go there myself yet).

  • @anjelpatel36

    @anjelpatel36

    4 жыл бұрын

    @@phil.4688 This, is so important. The math really doesnt click unless you write down where each derivative comes from. And the fact that you need more than one partial derivatives for each layer.

  • @danielcampelo2

    @danielcampelo2

    4 жыл бұрын

    @@phil.4688 Exactly what i had to do. Was getting the concepts, but only really understood once i started taking notes, and perform the calculations by myself (took even more time as had to re-learn derivatives...). The most interesting is that, now that i understood it, i'm even more appreciative the way it's explained in the video.

  • @arnavrawat9864

    @arnavrawat9864

    3 жыл бұрын

    Some memorisation is required. The way to understanding is easily recalling the different pieces and how they fit together.

  • @kevinsommerfield6341

    @kevinsommerfield6341

    3 жыл бұрын

    I hear you. I rewatched videos 1 and 2 in this series earlier, and will be rewatching videos 3 and 4 later.

  • @SaifUlIslam-db1nu
    @SaifUlIslam-db1nu5 жыл бұрын

    It has taken me about 3-4 days worth time to understand all of these 4 lectures, lectures which are in total, no longer than 1 hour and 30 minutes. And I feel proud.

  • @debajyotimajumder2656

    @debajyotimajumder2656

    4 жыл бұрын

    you should get the t-shirt-merch from 3b1b's description site, the shirt says "pause and ponder"

  • @danielcampelo2

    @danielcampelo2

    4 жыл бұрын

    Same here. Took my time to hear all explanations. This last video is by far more complex than the previous ones, yet still very well explained.

  • @polycreativity

    @polycreativity

    3 жыл бұрын

    I'm attempting to implement it from scratch in C# with no matrix math library or anything so I can get a feel for the nuts and bolts. This is the boss level!

  • @polycreativity

    @polycreativity

    3 жыл бұрын

    @@berkebayraktar3556 Yeah, I'd love to once I can get it to train properly! So finicky.

  • @vibaj16

    @vibaj16

    3 жыл бұрын

    Daniel McKinnon me too! I’m working on the back propagation, this math is hard

  • @yashjindal9822
    @yashjindal9822 Жыл бұрын

    I just started out with my ML career. This entire series made me feel as if I knew it all along. Thank you Grant I will return to this comment to share my professional progress😊

  • @Mayank-lf2ym

    @Mayank-lf2ym

    6 ай бұрын

    Now it's time to return to tell your progress

  • @azibekk

    @azibekk

    3 ай бұрын

    Any update?

  • @rmmaccount

    @rmmaccount

    2 ай бұрын

    we are waiting

  • @SaintKhaled
    @SaintKhaled Жыл бұрын

    The quality of this education is top-tier. I absolutely am speechless that you make it freely accessible. Thank you so much!

  • @shofada
    @shofada6 жыл бұрын

    This is how 21st teaching should look like. It feels like your work should be made a "human right". Thank you.

  • @fakecubed

    @fakecubed

    3 ай бұрын

    No human has the right to another human's labor. That's called slavery.

  • @snf303
    @snf3032 жыл бұрын

    At time when I just finished my university - I could not imagine that at one chilly Sunday evening, in almost 15 years after the graduation, I will sit with a bottle of beer, watch math videos, and have so much fun! Thank you!

  • @thiyagutenysen8058
    @thiyagutenysen80584 жыл бұрын

    I came here after Andrew Ng's week 5 in coursera and you blew my mind

  • @whereismymind1841

    @whereismymind1841

    4 жыл бұрын

    Oh my god, me too

  • @tuxfighter

    @tuxfighter

    4 жыл бұрын

    here too :D

  • @DMDRPBHU

    @DMDRPBHU

    4 жыл бұрын

    yeah bcz of corona..bw i am doing it for free

  • @bryancheong924

    @bryancheong924

    4 жыл бұрын

    same bro

  • @masrursakib6528

    @masrursakib6528

    4 жыл бұрын

    Same bruh

  • @vectozavr
    @vectozavr6 жыл бұрын

    That is the reason for learning the math! To understand such a beautiful things! That is awesome! Thank's a lot!!!

  • @anthead7405

    @anthead7405

    3 жыл бұрын

    Math on his own is also the reason for learning math.

  • @vvii3250

    @vvii3250

    3 жыл бұрын

    Интересно повстречать тебя тут. :)

  • @owaisfarooqui6485

    @owaisfarooqui6485

    3 жыл бұрын

    and when I asked my math teacher, that person told me you need this to pass the test. that didn't make a lot of sense back then

  • @krenciak

    @krenciak

    3 жыл бұрын

    @@vvii3250 Ага, чувствую себя как в своеобразном мини-клубе, где собралась небольшая компашка и тусуется))

  • @bocik2854

    @bocik2854

    3 жыл бұрын

    @@krenciak Ыыыыыы

  • @antoniobernardo9884
    @antoniobernardo98846 жыл бұрын

    this is easily the best channel in youtube today! once I get a job i will more than glad to support you!

  • @utsavprabhakar5072

    @utsavprabhakar5072

    6 жыл бұрын

    Exactly what i was thinking!

  • @chinmayrath8494

    @chinmayrath8494

    4 жыл бұрын

    It has been two years. Have you supported yet??

  • @pranaysingh3702

    @pranaysingh3702

    4 жыл бұрын

    Did you get a job ?

  • @fitokay

    @fitokay

    4 жыл бұрын

    Two years ago, could you get AI job?

  • @hozelda

    @hozelda

    4 жыл бұрын

    @@fitokay I think AI won and got his job.

  • @vladimirfokow6420
    @vladimirfokow64202 жыл бұрын

    Thank you a lot for this series! It has really helped me get into this topic, and changed my life. Your intuitions have been immensely helpful in my efforts to understand backpropagation. I just can't overestimate, how great your channel is!

  • @vgdevi5167

    @vgdevi5167

    Жыл бұрын

    Hello, I'm greatly impressed by the way he explained this topic too, but I'm looking for more such great quality resources, youtube channels, books on deep learning, and also math and comp science in general, what do you recommend?

  • @alexdebate7081
    @alexdebate708110 ай бұрын

    Grant, I've come back to this series many times over the last five years. Every time I do, I pick up more and more pieces of the puzzle. I think I've finally got it now, but we shall see! Thank you!

  • @borg286
    @borg2866 жыл бұрын

    The point where you addressed the concern that the example you were using was too simple, having only 1 edge, was spot on as you were leading me down this merry garden path. I appreciate how much you watch your own videos and predict where the watcher would mentally say, "but what about..."

  • @altaypbank9036

    @altaypbank9036

    3 жыл бұрын

    0;090505452 0145

  • @sergiokorochinsky49
    @sergiokorochinsky496 жыл бұрын

    I just unsubscribed to this channel, so I can have the pleasure of subscribing again.

  • @pranavnigam11

    @pranavnigam11

    3 жыл бұрын

    I just unliked your comment... So I can have the pleasure of liking it again

  • @ifusubtomepewdiepiewillgiv1569

    @ifusubtomepewdiepiewillgiv1569

    3 жыл бұрын

    i just liked and then unliked ur comment bc i realized it was at 69

  • @etsagcoenagpur1200

    @etsagcoenagpur1200

    3 жыл бұрын

    @@ifusubtomepewdiepiewillgiv1569 nice

  • @neillunavat

    @neillunavat

    3 жыл бұрын

    "Not gonna lie, you got me in the first half"

  • @neillunavat

    @neillunavat

    3 жыл бұрын

    @@ifusubtomepewdiepiewillgiv1569 .

  • @vedant7090
    @vedant70903 жыл бұрын

    Man u deserve a Nobel Prize for teaching Machine Learning with this simplicity.

  • @cineblazer
    @cineblazer3 жыл бұрын

    I'm taking Machine Learning by Andrew Ng on Coursera right now, and just got stuck on backpropagation. Thank you thank you thank you thank you Grant, you have no idea how incredibly helpful your videos are and how much your channel has inspired me through the years.

  • @rembautimes8808

    @rembautimes8808

    2 жыл бұрын

    I was in the same position 2 years back . This video does clarify the topic - tremendously

  • @mrflyswat

    @mrflyswat

    2 жыл бұрын

    Here I am. Same situation. Andrew Ng course and backpropagation is rough. This video in particular really helped to clear things up. Breaking it down to a single neuron is enormously helpful.

  • @barditheweird6062

    @barditheweird6062

    2 жыл бұрын

    Same here!) I was somewhat disappointed when Andrew Ng course just through the formulas at me, so I tried to derive backpropagation myself and got stuck in all the little details. Thankfully, 3b1b rode in like a knight in shining armor and now I am really damn happy))))

  • @mo_l9993

    @mo_l9993

    2 жыл бұрын

    I think the wheel gets repeated with every new comer !

  • @vgdevi5167

    @vgdevi5167

    Жыл бұрын

    Hello, I'm impressed by the way he explained this topic too, but I'm looking for more such great quality resources, youtube channels, books on deep learning, and also math and comp science in general, what do you recommend?

  • @Ensorcle
    @Ensorcle6 жыл бұрын

    I cannot tell you how much I appreciate these videos. I don't have a strong math background (english undergrad) but I'm teaching myself data science. It REALLY helps to have the equations explained rather than just presented and to tie the components of the equation back to intuitions. Thank you thank you thank you.

  • @bradleydennis210
    @bradleydennis2104 жыл бұрын

    I just finished up calc iii this semester and I have never felt happier with myself for being able to apply my new knowledge than this episode. I also don't think I have ever been more excited to hear calc iii topics being brought up in a field I am trying to teach myself currently. Thank you for making such a simple to understand series!

  • @Kevin-cy2dr
    @Kevin-cy2dr4 жыл бұрын

    Honestly this channel doesn't deserve a dislike button. It took me days to figure out one video(at the beginning),but the concepts remain still in my head. This channel taught us that maths is not just changing numbers, but its conceptual and intuitive just like science. Grant if you are ever read this, please know that you are one of the very few people that change the world. I just dont have words for you man, great job is an understatement for you. I promise once i earn enough i will contribute to your channel

  • @mooglefan
    @mooglefan4 жыл бұрын

    I've worked with AI for 2 years now. I have never seen anyone explain this as succinctly and aptly as you have. This video is legitimate gold. Going to show this to anyone who needs an explanation in future!

  • @jaysoaring6318
    @jaysoaring63186 жыл бұрын

    If there is an award for educational video series on advanced scientific matters. Please give this award to 3b1b. Love it!

  • @thfreakinacage
    @thfreakinacage6 жыл бұрын

    My god! A basic machine learning video series that actually makes sense to completely beginners! Subscribed, and waiting in great anticipation for the next one! :D

  • @LimitedWard
    @LimitedWard4 жыл бұрын

    Absolutely brilliant explanation! I took a course on deep learning in college, but ended up auditing it in the end because I couldn't grasp the concepts well enough to pass the tests. You just took the entire first unit of the course, which took several weeks, and condensed it into 4 easily digestible videos that anyone can understand!

  • @ashkankiafard4493
    @ashkankiafard44932 жыл бұрын

    The fact that I can understand what you're talking about shows that your teaching is flawless!

  • @samuelreed5481
    @samuelreed54815 жыл бұрын

    These videos are unbelievably well produced. Thank you so much for your effort. You've made this topic incredibly clear and I cannot understate how much I appreciate the amount of effort you put into these. You have incredible talent as a teacher.

  • @Erioch
    @Erioch6 жыл бұрын

    Honestly, this is one of the best (If not the best) channel on Mathematics/Science education I have seen. Intuitive but not oversimplified. Thank you so much that for offering your spectacular work and you help so many people understand these concepts.

  • @jamesjin1668
    @jamesjin16683 жыл бұрын

    All of the animation you used are so simple yet at the same time so illuminating. I bet people would appreciate your videos even more when at the end of the video you zoom out to show all of your visual aid in a nicely summarized flow chart / spatial diagram.

  • @nomasan
    @nomasan27 күн бұрын

    Rewatching this over and over and over again... that really does help with understanding it. It builds connections in the brain

  • @Redrumy0
    @Redrumy05 жыл бұрын

    Literally the only youtube channel, that makes studying 2 hours of math, go by in a blink of an eye

  • @sainandandesetti3268
    @sainandandesetti32684 жыл бұрын

    Stunningly beautiful... The best part of the series (for me, obviously) is that the beauty of this series does NOT make it very easy to understand. No. Each video may need multiple views. But these videos are so beautifully made that you'd want to watch them again and again, not with the frustration of getting your head over a concept but with the thrill of unravelling a mystery... So for creating such excitement in me, thank you.

  • @michaelarmstrong2251
    @michaelarmstrong225110 ай бұрын

    Just watch this series of videos. I'm a mechanical engineer with no prior experience of machine learning - now I feel like I understand quite a few concepts that were hard to wrap my head around when learning from other sources. Absolutely awesome videos - well done!

  • @n9537
    @n95374 жыл бұрын

    This 10 min video is pure gold. Lays down the math in an easy to understand, intuitive manner.

  • @giron716
    @giron7166 жыл бұрын

    I seriously have a hard time explaining how much I appreciate this video. I am far and away a symbolic thinker, as opposed to a geometric one, and while I love all of your videos and how intuitive you make the concepts, it's sometimes hard for me to think about the geometry. I am much more comfortable working with symbols and that's why I treasure videos like this. Thank you :)

  • @samarthsingla1082
    @samarthsingla10825 жыл бұрын

    The amount of help you are providing is nothing short of amazing.

  • @gibemass6578
    @gibemass65785 жыл бұрын

    You are some sort of sorcerer. The chain rule was finally elucidated for me in about 20 seconds. So concise and intuitive indeed. That was one thing, for whatever reason, I couldn't get my head around as a younger student. Big props man. Love this channel.

  • @rohitdatla724
    @rohitdatla7244 жыл бұрын

    u r not just teaching NN concept but how to think, break down and understand any complex problem and digest, U R AWESOME!!!!!

  • @micahsheller101
    @micahsheller1016 жыл бұрын

    Beautiful work! Reminds me of my late father who was a math professor: he had the same gentle, happy style, and believed heartily in making math a safe place for everyone to learn and have fun. Gonna make me tear up :)

  • @kangChihLun
    @kangChihLun6 жыл бұрын

    This is the best and clearest explanation in all BP course I could find ! 沒有之一!

  • @songlinyang8614

    @songlinyang8614

    5 жыл бұрын

    没有之一,haha

  • @OGLOCK69

    @OGLOCK69

    5 жыл бұрын

    Are you going to use this knowledge to help develop the social credit system?

  • @dysonsun3306

    @dysonsun3306

    5 жыл бұрын

    kang Chih Lun 哈哈哈哈哈

  • @shengchuangfeng227

    @shengchuangfeng227

    5 жыл бұрын

    Good! 沒有之一!

  • @user-jf5bw7mf9y

    @user-jf5bw7mf9y

    5 жыл бұрын

    you are right! 没有之一,哈哈哈

  • @bean217
    @bean2172 жыл бұрын

    I am currently going through Michael Nielson's "Neural Networks and Deep Learning" book. This video helps to clear up and visualize the chapter on back propagation a lot. Thank you for making this video series.

  • @PatryczakPL
    @PatryczakPL Жыл бұрын

    I really can't believe how well and simply this is explained here by you, I still keep coming back to this exact video even after few years of being in AI to refresh the fundamentals and to this day this is the best resource for this.

  • @elizfikret7489
    @elizfikret7489 Жыл бұрын

    Thank you so much! I have understood more math from this channel than from all teachers I have had in high school or university in total.

  • @vgdevi5167

    @vgdevi5167

    Жыл бұрын

    Hello, I'm impressed by the way he explained this topic too, but I'm looking for more such great quality resources, youtube channels, books on deep learning, and also math and comp science in general, what do you recommend?

  • @AnshulKanakia
    @AnshulKanakia6 жыл бұрын

    I can't tell you how long I've been trying to visualize all this in my head to get a solid mental picture of backpropagation... Well, I guess I can - it was the duration of a flight from Frankfurt to Seattle (about 9 hours) and it involved one terribly lit backside of an airplane menu and a shitty pencil. I am so grateful for the work you put into animating this algorithm. It has literally brought tears to my eyes and a smile on my face. Thank you.

  • @homieboi5352
    @homieboi53522 ай бұрын

    I’m gonna need to rewatch this a few times to grasp it all, but wow, what a thorough explanation of back propagation! I adore how you referenced the entire equation earlier in the series and it made no sense, but now you’ve broken it down entirely. Phenomenal work!

  • @bigbluetunafish4997
    @bigbluetunafish49978 ай бұрын

    Finally I finished these 4 chapters of neural networks, and some of your linear algebra and calculus stuff. I feel much better that now I have deeper understanding of how neural network works and have built up that base for further exploration of machine learning. Thanks very much for your effort creating all these great videos together.

  • @sjgmc
    @sjgmc6 жыл бұрын

    As an hobbyist programmer, i can't thank you enough! Once i finish my studies i will donate to you. :)

  • @zilongzhao3274
    @zilongzhao32743 жыл бұрын

    your video should be shown in every university's lesson, the animation makes the calculation just so easy to understand.

  • @vivekpujaravp
    @vivekpujaravp Жыл бұрын

    Your insight and eloquence are exquisite. You are quite possibly the greatest educator to ever exist. Thank you for everything, please keep making more. I will continue studying and appreciating your brilliant work.

  • @Arthur-fz5dw
    @Arthur-fz5dw3 жыл бұрын

    This NN series was amazing, thank you so much! I've watched a lot of these kinds of videos, read several online articles, and am following a popular online course. This series is the best resource by far, so helpful.

  • @Jabrils
    @Jabrils6 жыл бұрын

    youre a deity Grant

  • @Jabrils

    @Jabrils

    6 жыл бұрын

    Haha, why hello Bill. Nice to find you on 3B1B's channel :D

  • @bevel1702

    @bevel1702

    5 жыл бұрын

    wut

  • @anjelpatel36

    @anjelpatel36

    4 жыл бұрын

    wut

  • @gumbo64

    @gumbo64

    3 жыл бұрын

    wut

  • @idr7789

    @idr7789

    3 жыл бұрын

    wut

  • @saptarshimitra1267
    @saptarshimitra12676 жыл бұрын

    Amazing man..... I say 3gold1platinum

  • @General12th

    @General12th

    6 жыл бұрын

    More like 3plutonium1antimatter

  • @TwentySeventhLetter

    @TwentySeventhLetter

    6 жыл бұрын

    Yeah, cause he nukes the brains of laymen like myself.

  • @General12th

    @General12th

    5 жыл бұрын

    @@ishwarkarthik327 It's not.

  • @austinellis-mohr2189
    @austinellis-mohr21894 жыл бұрын

    I am continually impressed by your videos. Your essence of linear algebra lit up my imagination which such a geometric interpretation of the subject, and I have used your general methods many times in teaching others (both calculus and linear algebra). This is, in my opinion, the most beautiful series yet as it concisely describes a sort of mystified topic. The analogies you draw and even the notation you use is clear, informative, and friendly. I just want to say thank you and let you know that even outside of people watching your videos, your imagination and passion for teaching affects a lot of people’s learning in a variety of subjects. Again, just thank you and keep being a great teacher for literally millions.

  • @omerfarukozturk9720
    @omerfarukozturk97202 жыл бұрын

    literally thank you. I learned the information that I could not learn at school for 5 weeks in a 10-minute video. The animations of the video are absolutely magnificent. Thank you thank you thank you

  • @kirilllosik7054
    @kirilllosik7054 Жыл бұрын

    Thanks a lot for creating such a fantastic content! Anticipating to see more videos about AI, ML, Deep Learning!

  • @ehsanmon
    @ehsanmon6 жыл бұрын

    Thank you so much, Grant. I finally learned back prop, and I have become a patron. I wish I could do more.

  • @atiehhisham
    @atiehhishamАй бұрын

    This series explained all of this to me 100x better than the courses I paid for. You are a genius, keep up the great work !

  • @amulya1284
    @amulya1284 Жыл бұрын

    never in my life have I come across a calculus video explained so beautifully! in awe with this intuition

  • @MeriaDuck
    @MeriaDuck6 жыл бұрын

    After seeing a few pieces of books, descriptions on the internet about back propagation, with this video I finally reached some kind of enlightenment (especially at about 4:50 into this video). Thank you so much for that! Just as a hobby, I was trying to implement a neural network from scratch in java: plain objects for neurons, connections and layers. I wanted to really visualize how a neural network WORKS. (Visualize either as computer code, but maybe I even want to create some visual for it...) This will certainly help me on my way!

  • @nairanvac79
    @nairanvac795 жыл бұрын

    Thank you for starting your indices at 0.

  • @dteja92
    @dteja925 жыл бұрын

    God Bless You man! I have tried watching many videos about backpropagation but this series made my conceptual understanding and intuition super clear. Thanks a lot. You have no idea how happy I am right now to have understood the concept of backpropagation.

  • @13thxenos
    @13thxenos6 жыл бұрын

    Nicely done video. I knew I learned backpropagation before, but it was hard, and I didn't use it manually ( I used frameworks like TensorFlow which uses computational graphs and backpropagate automatically) so I've forgotten how it actually worked. But this video is a great resource for newcomers to ANNs and people like me that have forgotten the theory behind it all. Thank you.

  • @kimtheass1
    @kimtheass16 жыл бұрын

    You videos have such informative and well explained content with an amazingly calm and including tone! I'm a fan

  • @youngsoochoy5592
    @youngsoochoy55924 жыл бұрын

    This is the best mathematical explanation about the backpropagation of neural network. I've watched other coursera courses twice, but nothing can be compared to this well-visualized and easy to understand explanation.

  • @Mizar88
    @Mizar883 жыл бұрын

    I am speechless. This channel undoubtedly contains the best pedagogical scientific material on KZread, and possibly in the world. Thanks for making these videos, your skills and passion are unreachable!

  • @prashamsht
    @prashamsht5 жыл бұрын

    One of the best lectures I have ever heard. Great explanation of NN, cost functions, activation functions etc. Now I understand NN far far better...(P.S. I saw previous videos Part 1, 2,3 as well)

  • @notbobbobby
    @notbobbobby6 жыл бұрын

    Right now, I am so thankful for having taken vector calculus and several numerical approximation courses. This was an AWESOME video to watch. Thanks! :)

  • @steelcitysi
    @steelcitysi4 жыл бұрын

    This was the best animated description I've come across. I hope you can continue on this topic more. Especially interested in the jump to CNNs, and the intuition for the effects of changing the number of layers and number of nodes in the hidden layers.

  • @joecjaffe
    @joecjaffe Жыл бұрын

    LOVED these four introductory videos. My brain was so exhausted processing them--lots of pausing--but I feel like I get something conceptually that I knew near nothing about a couple days ago. Great foundation to scaffold the programming and math onto. Thank you! will definitely be watching more of your videos. Looking forward

  • @tcc1234
    @tcc12345 жыл бұрын

    I saw a 6.5 minute ad (related to AI) in order to support you. Keep up!

  • @sacation6057
    @sacation60575 жыл бұрын

    Awesome series! Even though i already had quite a intuitive feeling about the concepts of Deep learning, your videos just always make complex subjects click in my mind, it sort of forms the right connections between the neurons in my mind i suppose so ;) Even without any advanced math knowledge i was able to follow your math, so thanks for choosing to keep your examples as simple as possible! I'm gonna make my own network from scratch in code some time, to see if i truly understand it throughly.

  • @kazenokize2
    @kazenokize23 жыл бұрын

    I just watched this video going back and forth several times and I am at a point where I am not sure if it made sense or not, but I still feel like it helped. Thank you so much for this series!

  • @hunteranderson5573
    @hunteranderson557311 ай бұрын

    This is hands down the best resource I have seen on the calculus of backprop. I have called back on my knowledge gained from this video many times, it has been invaluable in my understanding of the current machine learning landscape. Excellent work with the notation too. Incredibly valuable video put together perfectly, good work 3b1b!

  • @matthewhaythornthwaite754
    @matthewhaythornthwaite7543 жыл бұрын

    If anyone is interested, I worked through the chain rule for the differential of the cost function w.r.t the weight in the second layer down. Two additional terms are added to make everything cancel as they should. It shows how as you progress down the layers, more partial differentials are added to the equation from all the variables above, making it more unstable and hence more susceptible to the exploding or vanishing gradient problem. dC/dw(L-1) = dz(L-1)/dw(L-1) * da(L-1)/dz(L-1) * dz(L)/da(L-1) * da(L)/dz(L) * dC/da(L)

  • @galileofrank5779

    @galileofrank5779

    3 жыл бұрын

    what's the vanishing gradient problem?

  • @MrJmayz

    @MrJmayz

    3 жыл бұрын

    i'm looking for this in the video. appreciate if you could share your work

  • @patelnirmal4726
    @patelnirmal47266 жыл бұрын

    Awesome channel

  • @martinmartin6300
    @martinmartin63004 жыл бұрын

    Great explanation! I like how you really focus on giving why the formulas actually help and to make this stuff as intuitive as possible. This is the best inteoduction on backpropagation that I have seen so far!

  • @catchingphotons
    @catchingphotons3 жыл бұрын

    Unarguably one of the best "tutorial" videos of all times! The carefully taken logical steps of understanding, the animations, the visualizations, the tempo, the examples... boggles my mind! This is a masterpiece! Greetings -Chris

  • @aravindkannan9490
    @aravindkannan94906 жыл бұрын

    This is by far the best video I have ever seen in Neural Networks. Thanks for this! :)

  • @tisajokt7676

    @tisajokt7676

    6 жыл бұрын

    I also suggest the video series on neural networks by Welch Labs, or if you've seen it already, I'd be interested to hear your comparison between it and 3Blue1Brown's series.

  • @aravindkannan9490

    @aravindkannan9490

    6 жыл бұрын

    Just completed their playlist! equally good :) I like the application-oriented explaination However, I would still recommend 3B1B for an absolute beginner because of the in-depth explanation and for the help in visualizing the math behind it

  • @annemarieenpieterbresters-3876
    @annemarieenpieterbresters-38766 жыл бұрын

    this must have taken so much time, I was able to just understand it now (after using my whole evening yesterday)

  • @vil9386
    @vil9386 Жыл бұрын

    How easy it is to understand this through your lectures in just 10minutes. THANK YOU.

  • @JinruWu
    @JinruWu8 ай бұрын

    This is back propagation so brilliantly explained, I can now feel how efficient this way of calculation is and how it enabled computation not in the past possible. Teaching a Deep Learning course next week and have been scratching my head understanding this concept - now I'm confident I will be able to explain to my students with clarity. Thank you so much! You have touched my life as well as theirs :)

  • @GaborGyebnar
    @GaborGyebnar6 жыл бұрын

    Awesome material. :) Please make a video about convolutional neural networks, too.

  • @antopolskiy
    @antopolskiy6 жыл бұрын

    this is sooooo useful. thank you so much for breaking it down so great. I feel like I have a full picture in my head now.

  • @aaradhyadixit9564
    @aaradhyadixit9564 Жыл бұрын

    one of these best videos out there that explains the basics of neural networks, gradient descent, backpropagation in such easy language and intuitively. Great work!!

  • @ciherrera
    @ciherrera5 жыл бұрын

    Wow, this took a long time to get my head around fully, but I was finally able to understand it enough to implement my own version of backpropagation from scratch thanks to this video! Neural networks are something I've wanted to get into for a while and I'm really grateful for these wonderful in-depth explanations!

  • @thomasschwarz1973
    @thomasschwarz1973 Жыл бұрын

    This is truly awesome, as pedegogy and as math and as programming and as machine learning. Thank you! ...one comment about layers, key in your presentation is the one-neuron-per-layer, four layers. And key in the whole idea of the greater description of the ratio of cost-to-weight/cost-to-bias analysis, is your L notation (layer) and L - 1 notation. Problem, your right most neuron is output layer or "y" in your notation. So one clean up in the desction is to make some decisions: the right most layer is Y the output (no L value), because C[0]/A[L] equals 2(A[L] - y). So the right most three neurons, from right to left, should be Y (output), then L then L minus one, then all the math works. Yes?

  • @AbhishekKumar-bo1yi
    @AbhishekKumar-bo1yi6 жыл бұрын

    I always feel, if u have a mentor who can break complex things into simple stuff so beautifully, even a dumb guy can grasp the concept. Keep doing the good stuff. Admirer++

  • @aditiparetkar2862
    @aditiparetkar28622 жыл бұрын

    One of the best series on Deep Learning .. watched all four videos and all were totally worth it. Thankyou for all the time and effort that goes into making these videos

  • @T.RiceBae
    @T.RiceBae Жыл бұрын

    Nothing more but a deep thank to you for making such amazing video. I truly cannot express how much this whole series had clarified this topic for me. Again, thank you very much.

  • @Abstruct
    @Abstruct6 жыл бұрын

    This stuff is an amazing supplication to Andrew Ng's courses, it gives a lot more intuition and visual understandings of the formulas.

  • @claytonharting9899

    @claytonharting9899

    6 жыл бұрын

    It certainly is a huge help for backprop. Just the tree visual is a huge help. Btw, what do you think of 3b1b’s use of a bias value vs Ng’s use of a weighted bias node? I think 3b1b’s may be more clear, but the node version is more computationally efficient.

  • @Viplexify

    @Viplexify

    6 жыл бұрын

    ... in which Ng mentioned that he still doesn't fully understands backprop. I wondered if it was true or just a consolation for beginners.

  • @ab452

    @ab452

    6 жыл бұрын

    Consolation, it is just to sooth your frustration. But he can also be referring that you can understand how to compute it for a simple case ,but it in a large instance you simple lose track of it. Without a computer is would be a hopeless task.

  • @tanmaybhayani

    @tanmaybhayani

    4 жыл бұрын

    andrew should link this series in his course, cos this is just beautiful!

  • @hayden.A0

    @hayden.A0

    4 жыл бұрын

    I'm actually here in between Andrew Ng's course on machine learning. there were a few concepts I didn't completely understand but they are quite clear now.

  • @alexandrugheorghe5610
    @alexandrugheorghe56106 жыл бұрын

    Excellent lesson! Thank you very much.

  • @kamilchosta5526
    @kamilchosta55262 жыл бұрын

    You bring clarity on such potentially complex ideas as Prometheus brought all the light to everyone in the mythology. We are forever grateful for your efforts! You are a math artist and this videos are a masterpieces conveying intuitive understanding of such complex ideas to many people.

  • @fossar_
    @fossar_2 жыл бұрын

    Had this recommended to me by KZread for weeks now and glad I've finally have time to sit down and watch the miniseries. Excellent videos.

  • @lagduck2209
    @lagduck22096 жыл бұрын

    *looking at thumbnail oh sh~, Im never going to understand that complex stuff. probably should watch it anyway *ten minutes later whoa! that's actually quite clear now!

  • @kairostimeYT

    @kairostimeYT

    6 жыл бұрын

    same for me.

  • @alex-gb9iy

    @alex-gb9iy

    6 жыл бұрын

    Тоже учишь нейросети?

  • @lagduck2209

    @lagduck2209

    6 жыл бұрын

    просто люблю математику и познавательные видео на эту тему) особенно нейросети

  • @sage5296

    @sage5296

    6 жыл бұрын

    I think that’s kinda the point of much of this channel lol. Same experience though! It’s amazing how a KZread video can do so much teaching in like 10 minutes

  • @tommysawyer9680

    @tommysawyer9680

    6 жыл бұрын

    I had the same reaction. Beautifully broken down into calculus us mere mortals can understand!