Attribution gotchas

Attribution tells you which marketing touch drove a conversion. Multiple models exist; none are perfect.

Models

• Last-click (simple, biased to bottom of funnel)
• First-click (biased to top)
• Linear (equal weight)
• Data-driven (algorithmic)

CRO-specific concerns

• Same-user multi-touch: which page gets credit?
• Cross-device: hard to attribute
• Delayed conversions: attribute to session or first-touch?

Pragmatic

Use platform attribution for directional signal, test for specific optimization, holdouts for truth.

What to do with this

• Pick one attribution model for reporting, switching between models confuses stakeholders and hides trends
• Use last-click for tactical optimization, data-driven or MMM for strategic allocation
• Don't trust platform attribution as truth, it over-claims and is directional only
• Run quarterly holdout tests to validate attribution assumptions, models drift from reality over time
• Track blended MER alongside platform attribution, the gap tells you how much the models are over-claiming