Scatter Slider : Correlation & Line of Best Fit mod
This applet was shared by tlindy and was slightly modified by JimD.
Move the scatter slider back and forth between "Strong Negative" and "Strong Positive" correlations.
Note that with a perfect negative correlation (r= -1.00), all of the points fall on the best-fitting line (r^2= 1.00).
Note that with a perfect positive correlation (r= +1.00), all of the points fall on the best-fitting line (r^2= 1.00).
Note that the "MnXMnY" point (Mean of the Xs, Mean of the Ys) always falls on the best-fitting line.
When r= 0, the best-fitting line provides no useful prediction (r^2= 0). The best one can do is to always predict (Mean of the Xs, Mean of the Ys).