Geo Experiments: The Complete Guide to Measuring Marketing Incrementality
Your ad platform says the campaign delivered a 4.2 ROAS. Your finance team looks at total revenue and sees no change. Both of them are reading real numbers. Only one of them is measuring what the campaign actually caused. This gap is the single most expensive measurement problem in marketing, and it exists because attribution answers the wrong question. Attribution asks which touchpoint preceded the conversion. The question you actually care about is what would have happened if we hadn't run this at all. Those are different questions, and no amount of clean tracking will turn the first into the second. Geo experiments are the most practical way to answer the second question at scale. This guide covers what they are, when they earn their keep, how to design and analyze one properly, and where they fall short.
