Offline attribution links marketing activity to sales that happen in physical stores, so each campaign or placement gets credit for the purchases it influenced. Online attribution follows clicks and cookies; offline attribution has to connect exposure in the physical world with a purchase at the till.
Retailers traditionally measure it with surveys and focus groups, before-and-after sales data, or tracking codes such as unique coupons. Each method answers part of the question, but none sees what happens between the ad and the shelf. Modelling attribution (attribution modelling and marketing mix modelling) estimates the contribution of each channel, but it depends on data quality, carries uncertainty and has to infer the step between exposure and purchase.
The main attribution models are first-touch, last-touch, linear and time-decay. Last-touch is the most common because it is simple, but it ignores everything that built the intent before the final touchpoint, which in retail usually means ignoring in-store media altogether. Our offline attribution guide compares them with a worked example.
Shoppermotion observes the missing step. Tags on trolleys and baskets record whether each shopper passed a placement, slowed down to look or stopped to engage, and at checkout the trip is matched with its ticket. Comparing exposed shoppers with a matched group that was not exposed gives the incremental sales and ROAS of each campaign. This is closed-loop attribution; read more in offline attribution for retail media.