A "Begin" button will appear on the left when the applet is finished loading.
This may take a minute or two depending on the speed of your internet connection
and computer. Please be patient. If no begin button appears, it is probably
because your browser does not support Java 1.1. Click here for
information on how to get a browser that does.
Starting
the Applet and setting the conditions
Press the "Begin" button to
start the applet in another window.
The simulation shows a scatterplot
of data from a bivariate distribution in which the relationship between the two
variables is linear. You can change the "input" values of slope,
standard
error of the estimate, or standard
deviation of X for this data sample, and see the effects of your change.
On the right side, a blue and red bar shows the total variance in Y for
the sample. The blue portion shows the amount
of variance explained by X; the red portion shows the amount of variance
unexplained.
The simulation also shows two "output" values, Pearson's
r and the standard
deviation of Y. These vary as a function of the three input values you can
set.
You can change any of the input values and observe the effect on the
scatterplot and the output values. Or, you can use the "animate" feature to
watch what happens as the values change. If you click any of the "animate"
buttons, the relevant parameter will change in small steps updating the
scatterplot and the output values. This may not work with all
browsers.
The same data sample is used for each change your make. To see
new random data that correspond to your input values, click the "new data"
button.