Example: Correlation coefficient intuition | Mathematics I | High School Math | Khan Academy

Sal explains the intuition behind correlation coefficients and does a problem where he matches correlation coefficients to scatter plots.

High School Math on Khan Academy: Did you realize that the word "algebra" comes from Arabic (just like "algorithm" and "al jazeera" and "Aladdin")? And what is so great about algebra anyway? This tutorial doesn't explore algebra so much as it introduces the history and ideas that underpin it.

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[fettishferrubbish]

Oh how funny! Yesterday, I was in a physics lab that explored frictional force. And to find the kinetic friction coefficient for a block covered in felt sliding along an aluminum surface, we measured the frictional force of the block by some kind of friction sensor and created a graph where frictional force was the Y and the Normal force acting on the block was the X. With these data points...we created a best fit line...and the slope of that line was the kinetic friction coefficient. Anyways...one of the things we had to check for is what the correlation coefficient was. We managed to get correlation coefficient of .98. which meant that our data points created a line that was straight enough. Our experiment was a success!

[writerah]

Khan Academy,
I absolutely love what you stand for..free education.. Thank you. I have one constructive criticism..if I had a dime for every time you say something like..." We're not going to go into that right now, " or " That's beyond the scope of that right now." or " Well, that's a whole other subject that we can't cover now." I'd be a millionaire.

[omwfg]

In the last example the choices should be swapped between B to D. obviously fit matter but calculating r has to do with the ratio of x and y values. As you can see, the ratio depicted by line in graph D is more towards 1 to 1 than the ratio depicted by the line in graph B.

[xchamaquex]

Very help full when needing an example

[krisswift]

Awesome explanation!! My only confusion was that as you were crossing out your "r = 0.02" & "r = -0.72", it looked like you meant to imply that those have a positive correlation. Yes a bit nit-picky but I thought it was worth it to bring it up. Thanks again!

[mahirbehl]

I have a precalc midterm tomorrow. Now i know what residuals are. THANKS

[FROGGKINGG]

Sal sounds like a modded minecraft youtuber lol

[khudahafiz]

sir ...how to find correlation between two values .. I mean the values of r ... can you tell about the formula..plz

[deepapreetheesh]

If correlation between x and y is r then correlation between x^2 and y^2 is ???

[minjaeeeeee]

I believe the scatterplot B is 0.65 and scatterplot D is 0.84. R is the average slope right?

[yrebrac]

my subwoofer tells me there is no low cut on this video :) still, great video

[IQ]

hi, what software or device do you use??

[jaeyounglee]

Im in algebra 1 and I learned this...
and im in 7th grade...

[akairov]

hello! I think in Graph B r=0, 65 and in Graph D r=1