This applet allows you to enter data in a small spread sheet. As you enter the data the descriptive statistics and the correlation are computed, and a scatterplot of the data appears. This is illustrated in the following printout, using the data on Alcohol and Tobacco consumption in Britain that we saw in Table 9.3.
The purpose of the data in Table 9.3 was to illustrate the dramatic influence that a single data point can have. After you enter the data, modify the values of the last case (Northern Ireland) to bring them in line with the other observations, and see what affect that has on the correlation.
To enter the data, be sure that the cursor is blinking in the box to the upper left. Then enter your value and press Enter. The cursor will move down one row, and you can enter the next value. To begin entering values of Y, click once or twice on the box you want to enter, and then type the number followed by a return. To change a value, double click on the box, then select the entry in the box in the upper left and enter the new value.
Comments to: Gary.McClelland@Colorado.edu
Return to index