Calculate correlation coefficient with Excel.

1) Enter your data in adjacent columns. Start with meaningful labels. Enter each data point in separate cell under the appropriate label. Be sure to keep related data points in adjacent cells.

2) Calculate the mean for each variable by using the Average function. Click on an empty cell at the bottom of your columns of values, Click on the fx icon. Choose the Average function. Enter the range of cells for your data, e.g. B2:B28. Click on OK.

3) Calculate the standard deviations for each variable using the STDEVP function. (Follow the steps in 2 but substitute the STDEVP function for the average function).

4) Calculate the z scores for each variable.

5) Calculate the cross products of the z scores.

6) Label a blank column.

7) In the first cell enter the equation =D2*E2. In this case D2 is the cell containing the z score for the first value of your first variable and E2 is the cell containing the z score for the first value of your second variable.

8) Copy that equation to the remaining empty cells in that column.

9) Calculate the mean of these cross products.

Preparing a scatter plot with Excel.

1) Highlight two columns of data.

2) Click on the graph wizard icon.

3) Select the scatter plot icon and click on next.

4) Make any changes you think are appropriate in the graph; be sure to label your axes appropriately.