The best way for me to explain the problem might be to just give an instance of our data and the type of test/conclusion I am attempting to draw. Unfortunately as the title suggests, my understanding of econometric and statistics methods has waned.
The data consists of transactions, which occur at a restaurant. I am testing the impact of a change on a menu, removing two size options (small and large) and replacing them with one size option (call it medium.) I have about 20 test restaurants, and about 200 control restaurants, so about 10 of each control are mapped to a test for similarity in geography, etc.
That seems straight forward, however, unbeknownst to me, a test had begun to run at the same time which introduced a new flavor of a food item at our test restaurants. So, our restaurants for our testing period had both a size replacement (remove small large, introduce medium) and a flavor introduction (add flavor.) The data we collected includes a control period prior to our test with all restaurants, then a testing period, then a post testing period (which is where we noticed that the introduction of a new flavor may have corrupted our sample, having remembered that to have been the case.)
Is this something that could be solved with a 2 way ANOVA? If so where would I begin to dive in there? What other methods should I be exploring and how should I be setting these up?
I wanted this to be more of a discussion than a simple question and answer (because I doubt I would learn much from that.) But both are fine.