R-squared or coefficient of determination | Regression | Probability and Statistics | Khan Academy

R-Squared or Coefficient of Determination

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[alleyygal]

I think I've fallen in love with Khan. We've been through everything together; Statistics, Chemistry, you name it.

[oscarbergman]

Khan "Let me do this in an other color" Academy

[Musicthatmanifests]

and after all of the money that I spent on education... I just learned more without any pants on at home.

[NM-vwxq]

Thank you Sal! This was the best explanation of the R squared error I've seen ... makes a LOT more sense than just machine learning courses saying "its a percentage of how much it explains the variability of the data". This shows why that is, brilliant. Such a simple concept when broken down and explained visually step-by-step. You and 3B1B (also a former Khan Academy educator) are amongst the best instructors on YT.

[benjamcg]

1:03 What defines the error?
1:20 What defines total square error?
1:37 How y = (mx+b) relates to the error. 
2:55 "What % of the variation in y describes the variation in x?
6:30 What defines the squared error of the mean of y? (end)
6:59 What is not described by the variation in x?
12:38 What is the coefficient of determination, aka R²? (end)
10:23 What does R² say about the regression line?

[mevlutsoylu]

This video "literally" saved my butt. Thank you very much.

[angelbythewings]

Sal makes no presumptions about students coming to watch his lectures, and that's what has been helping me out. I have never met an educator better than him in my entire life, PERIOD

[georgedestino]

9:58 r squared is the Coefficient of determination

[coconutjoy]

Best explanation ever, imagine how many students around the world you have enriched!

[RajvimalCrystal]

Khan you are prodigy!!! only prodigy can teach as clear as crystal

[chocolatebubbles]

thank god for him because my own math teacher has absolutely no idea what he's teaching. he's not a statistician, it's his first year teaching stats, so i don't blame him.. but i'd be lost without sal & his vids. thanks again!

[jerilphilip]

Sal the saviour of pilgrims seeking conceptual clarity, as always.

[totalinsight]

Wonderful Mr. Khan. You have made this problematic concept seem so simple and 'intuitive'. Keep up this GOOD WORK.

[fridaylovebird]

Note potential confusion: "SE" in this video is the (sum of the) Squared Errors. However, usually "s.e." is standard error. Since, technically, we NEVER observe errors (because they are a function of the true regression line--we can estimate residuals, though), what is called "SE" here is actually the Sum of the Squared Residuals (SSR in some texts). I am torn whether to recommend this video to my stats students because of this likely confusion.

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Mr khan, youve been with me since i was at secondary school . And now im trying to understand how to do my papers and statistics, suprised to still see there is so much i can learn from you . Thank you for all of ur lectures.

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I wish everyone else would like and comment after enjoying a video, these likes and comments motivate us when we are in panic to quickly click into the video and cram before exam

[anesdj]

There is no easier way to explain regression as simple as that. thanks

[xgutierrezc]

I loved the explanation. Came here trying to understand the r2_score function in Python.

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I am glad I watched this, I am glad...glad..I am glad I watched this.