Research the usefulness of counterfactual theory in explaining the fundamentals of effect modification and interaction

Use online articles or resources at SDL library.
The paper assignment (500-1000 words (1 – 2 pages)) should be submitted on time. References should be APA style. Your assignment must have a completed cover sheet.
The assignment will be scored on each of the following elements; the answer is clearly described; the assignment is well written and organized; the student makes use of appropriate references.