Here's a freely available book / lecture notes doc that covers some of the ground you're interested in.
http://www.stat.rice.edu/~dobelman/courses/texts/Notes.411_6...
[1]: https://www.amazon.com/Design-Analysis-Experiments-Springer-...
[2]: https://www.amazon.com/Design-Experiments-Mike-Peralta/dp/14...
[3]: https://www.amazon.com/Design-Experiments-Approach-Bradley-J...
[4]: https://www.amazon.com/Design-Analysis-Experiments-Douglas-M...
The Scientific Method would be to propose a hypothesis, determine that the hypothesis would be supported is A was related to G, and then tell SPSS to run a crosstabulation of A and G.
Alas, the software can just as easily run a cross tabulation of all 380 possible combinations of variables. There is even a special command to do this. With p-Hacking I look through these 380 tables to find the one with the best correlation (let's say that is C and R). Then I try and guess up a theory that C being correlated to R supports.
I can't logically validate a hypothesis but only reject the opposite hypothesis.