2nd derivative r squared.

If you divide both sides of this by r squared, you get x squared over r squared plus y squared over r squared is equal to 1.

But then you have r squared minus r squared cancel out r to the third minus r to the third cancel out.

You multiply r squared times r you get r to the third.

So, the, the R squared was just the correlation squared, is the correlation between X and Y squared, that was your model R and that was your model R squared.

625 is equal to r squared.

So this right here is r squared, so if r squared is equal to 9, than r is equal to 3.

So this is r squared, this is the radius squared.

So 15 squared plus 20 squared is going to be equal to r squared.

Area is equal to pi r squared.

So if we were to divide both sides of this by r squared, we would get and this is just little algebraic manipulation x squared over r squared plus y squared over r squared is equal to 1.

If you multiply each of these terms by r, you multiply r to the first times r you get r squared.

This side squared, 3 squared, plus this side squared, plus 4 squared, is going to be equal to the absolute value of 3 minus 4i squared, the absolute value squared.

And that's going to be equal to r squared.

Remember the original formula I just showed you. x squared plus y squared is equal to r squared.

If we want to compare models, for example, we want, want to look at model A's R squared versus model B's R squared.

So this is plus r squared plus r to the third, plus all the way this is r to the n.

So the model R squared will not change at all.

If you have a circle centered at 0, its equation is x squared plus y squared is equal to r squared.

The general form of an equation, or the general equation for a circle, is x squared plus y squared is equal to r squared, where r is the radius of the circle.

Right, the value of 1 squared oh, right.

This, the r squared plus 5r, plus 6, is called the characteristic equation.

So the model R squared will take up A B C D E.

The measurement has a mean of nu and a covariance of r squared.

So the model r squared is the same as in the last segment.

You remember that if a circle is centered at 0, the standard form would be x squared plus y squared is equal to r squared.

R ...? R ...

So these T values, the P values, the R squared, those things don't change.

We learned in the last video that the equation of a circle is x squared and a circle centered at the origin. x squared plus y squared is equal to r squared.

So we know, if we want to solve for r, that this, r squared plus 5r, plus 6, that has to be 0.

It says the point minus 3, 2 lies on a circle whose equation is x plus 3 squared plus y plus 1 squared is equal to r squared.

And what's the second derivative? y prime prime is equal to derivative r is just a constant so derivative of the inside is r, times r on the outside, that's r squared, times e to the rx.

R, mom. Mom, r.

looked at the estimates in the R output And again, the model r squared doesn't change from the unstandardized solution to the standardized solution.

I'll write r to first this is going to be r squared, because if you square the numerator you just get a 1 again.

If it exists, the value and the time we saved it are in R.

I think you obviously see that y prime turns into r squared, y prime turns into r, and then y just turns into 1, essentially.

The value of that dollar would be 1 divided by 1.11 squared.

You should look at the standardized recursion coefficient or in lecture A, the model R squared.

Get some R and R?

The other thing I eluded to last lecture, and we didn't really get into simple regression is this idea when model R and model R squared.

So now, on to the model R and model R squared, for this model, the correlation between the observed scores and the predicted sores is 0.513.

r

r

R