Evidence provenance
In practice, for a UK buyer
The paragraph above is the neutral answer. This is the part a vendor glossary leaves out.
The mechanism that keeps four measurement verbs from collapsing into one flattering number. AdBuyMCP uses four labels: provider-reported, observed, modelled and powered causal, and only the last supports the word caused. The governing rule is blunt — no provenance label may advance on the strength of sandbox or API-shaped data — which is why no sandbox campaign can ever reach a causal grade, and none has.
What this one connects to
Most confusion in media buying comes from two adjacent terms being used interchangeably, so these are the neighbours worth reading next.
Attribution
Assigning credit for an outcome to the advertising touchpoints that preceded it, according to a rule the advertiser chose. A description of correlation in a conversion path, not a demonstration that the advertising caused anything.
Incrementality
The share of an outcome that happened because of the advertising, measured against what would have happened anyway. Measured by comparing an exposed group with a comparable unexposed one, not by counting conversions that followed an advert.
Marketing mix modelling (MMM)
A statistical method that estimates each channel's contribution to an outcome by regressing historical sales against historical spend and external factors. Works without personal data and covers channels that cannot be tracked individually.
Modelled
A number produced by a formula or an estimate rather than counted directly from observed events, and therefore carrying assumptions with it. Deduplicated reach and frequency across channels are the common examples, since no single seller can observe the others.
More on measurement and evidence
What you can prove afterwards, and the difference between a number that means something and a number that does not.
45 minutes. Bring a real brief and we compile it live. You describe one audience and watch it compile into seven targeting specifications, each with the score for how much of the definition survived.
Talk it through