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Starting the Applet and setting the conditions

Press the "Begin" button to start the applet in another window.

This applet lets you estimate the regression
line and to guess the value of Pearson's
correlation. Indicate your estimate of the regression line by drawing a
line on the scatterplot. When you release the mouse button, the mean square
error (MSE which is the average squared deviation of points from the line) is
displayed. You can draw another line and see if you can lower the MSE. To see
the best fitting line (by the criterion of least
squares) select the "Draw regression line" option. To see the
MSE for the best fitting line, select the "Show minimum MSE" option.

Five possible values of Pearson's correlation are listed. One of them is the
correlation for the data displayed in the scatterplot. Guess which one it is.
To see the correct value, click on the "Show r" button.

Click the "New Data" button to try again.