You may find it useful to read about validity first. See:
Validity Coefficient: Definition
Validity tells you how useful your experimental results are; a validity coefficient is a gauge of how strong (or weak) that “usefulness” factor is. For example, let’s say your research shows that a student with a high G.P.A. should perform well on the SAT and in college. A validity coefficient can tell you more about the strength of that relationship between test results and your criterion variables. In general, validity coefficients range from zero to .50. The possible range of the validity coefficient is the same as other correlation coefficients (0 to 1) and so, in general, validity coefficients tend not to be that strong; this means that other tests are usually required. It’s not unusual for validity coefficients to max out at around .30. For the above example, this low correlation means that some students with GPAs may not perform well on standardized tests or in college.
How to find Validity Coefficients
The validity coefficient is just another type of correlation coefficient. Therefore, you can use any statistical software to find validity correlation. For example, you can use the Excel CORREL function to find correlation coefficients:
- Type your data into a worksheet. Your independent variables should be on one column and your dependent variables should be in a second column.
- Click the function button on the toolbar (fx).
- Type “Correl” to find the Correl function. Click on “Correl.”
- Type the cell locations of your independent variables into the array 1 box. For example, A1:A30.
- Type the cell locations of your dependent variables into the array 2 box. For example, B1:B30.
- Click “OK.”
Click one of the links below to see directions for finding validity correlations in different software programs: