1. Carry out the summation of the scores of both groups.
2.Calculate the mean of the scores of both groups.
3.Square each of the scores of the subjects of both groups (Group 12 and Group 22).
4.Based on the squared scores, make the sum of the scores of both groups (Group 12 and Group 22).
5.Then the equation of the Sum of Squares must be applied see formula
For this formula, use the SUMMARY OF THE SQUARE SCORES and the SUMMARY OF THE SIMPLE SCORES.
The procedure is carried out first with Group 1 and then with Group 2.
6.After obtaining the results of the SUMMARY OF THE SCORES TO THE SQUARE OF GROUP 1 and GROUP 2, we proceed to apply equation 1.
7.Finally, formula 3 is applied in this way, the elements are complete to identify the associated probability of the hypothesis contrast.
8. Then we are located in the table t, with the degrees of freedom and the value of t, with these two data we can locate what is the associated probability for the value of t obtained, and compare with the alpha of 0.05 (See SPSS Comparison ). Although it is also possible to compare the value of t obtained with the value of critical t, which appears in the table based on the alpha used in Psychology, which is 0.05 of this if the value of t obtained> critical t, is rejects the null hypothesis and if the value of t obtained