Scenario

You are analyzing two experiments that ran at the same time on the same product surface. Experiment A changed the page layout and Experiment B changed the CTA copy. Users were independently randomized 50/50 into each experiment, creating four cells: A0B0 with 50,000 users and 4,500 conversions, A1B0 with 50,000 users and 4,900 conversions, A0B1 with 50,000 users and 4,700 conversions, and A1B1 with 50,000 users and 5,400 conversions. Use a 5% significance level.

Question

How would you determine whether each experiment has a real effect when both are running simultaneously, and whether there is evidence of interaction between them?