If you do a hypothesis to test the effectiveness of a treatment, or a marketing campaign, you want to be sure that the two groups are comparable.
You can compare some relevant quantities between the two groups. Even if these do not differ significantly, there may still be hidden differences between the two groups.
Suppose we compare costumer spending. The test group are costumers whose names start with the letter a, b, c, d, or e. The time and amount at check out are stored.
Can machine learning play a role in finding (statistically significant) differences between the groups?
Are there any references on this kind of use of machine learning?