Mathematical process for linking marketing activities to outcomes such as online or offline product purchases. Attribution modelling typically analyses the degree to which different blends of media exposure across different channels generate different bottom line results in order to establish causality and properly credit each media channel for its impact on the final outcome. For example, users exposed to $100K of display media only may generate 1,000 conversions that can be directly attributed to the display campaign, but also generate a measurable lift in searches and in offline sales that lead to further impact.