Marketing Attribution

Marketing attribution is the practice of assigning credit for a conversion to the marketing touchpoints that influenced it — the ads, channels, and interactions a customer encountered on the way to converting. It answers 'what actually drove this sale?' so budget can flow to what works. Because customers usually touch multiple channels before converting, attribution models decide how to divide the credit.

Common models include last-click (all credit to the final touch), first-click (all to the first), linear (credit split evenly), time-decay (more credit to touches nearer the conversion), position-based/U-shaped (most to first and last), and data-driven attribution (an algorithm assigns credit based on observed impact). Each tells a different story about which channels deserve budget.

Because customer journeys are long, cross-device, and partly invisible — privacy changes, cookie loss, walled gardens, and offline touches mean you never see the full path. Different models credit channels very differently, so the 'best' channel changes with the model you pick. Correlation isn't causation, and last-click in particular over-credits closing channels while ignoring the awareness that created the demand.

Match it to your goal and journey. Last-click is simple but biased toward bottom-funnel; first-click favors awareness; multi-touch (linear, time-decay, position-based) better reflects multi-step journeys; data-driven is most sophisticated where you have the volume and tooling. Many teams triangulate — using a multi-touch model alongside incrementality testing and media-mix modeling rather than trusting any single attributed number.

Attribution divides credit for conversions that happened across the touchpoints involved. Incrementality measures whether a channel caused conversions that wouldn't have happened anyway — the true lift over a baseline, usually via holdout experiments. Attribution can over-credit channels that capture demand they didn't create (e.g. branded search); incrementality tests whether the spend actually added conversions. The strongest measurement uses both.