What is attribution modeling?

Attribution modeling determines which marketing touchpoints get credit for conversions. A prospect might see a LinkedIn ad, read a blog post, receive an email, and then request a demo — which channel caused the conversion? Models: Last-click (100% credit to final touchpoint — simple but misleading), First-click (100% to discovery — ignores nurture), Linear (equal credit to all touchpoints — democratic but undifferentiated), Time-decay (more credit to recent touchpoints — reasonable default), Position-based (40% first, 40% last, 20% middle — popular compromise), Data-driven (ML-based, available in GA4 with enough data). For most B2B companies with fewer than 10,000 conversions per month, position-based or time-decay is the practical choice. Data-driven requires high volume to be statistically meaningful. The honest truth: perfect attribution is impossible. Focus on directional accuracy — knowing that content marketing drives 3× more qualified leads than paid ads is more useful than knowing the exact ROAS of blog post #47.