Module Nine    Part II: Experimental and Quasi-Experimental Research  

Continuation from Correlation -- Step 1  

Correlation -- Step 2 

The second step is to calculate the sums and means for each of the variables. Remember the mean is the sum divided by the number of scores. In this example, we have five scores. 
   

Table 2

 

Correlation -- Step 3 

The third step is to subtract the mean from the score. Always put the score first, then take the mean away from it. Be careful to keep your signs (+ or -). Do this for each score on both variables. If you are careful with your signs and sum this column, you will always get A0". This helps in checking your math.

Table 3