Alembic takes a holistic approach to attribution. We see all traffic, and the impact derived from the traffic on marketing efforts and ROI. Think of this as "reverse attribution." Alembic derives the attribution cohorts from the impact of the event surge, to the surge ripples, and back to the surge source. Alembic builds cohorts based on anonymized aggregates. This approach allows us to be a leading indicator, rather than a lagging indicator.