A checklist for defending an attribution finding
Seven things to have ready before the meeting, in the order they get asked for, including the two that most people cannot answer under pressure.
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By Joris van Huët, Founder & CEOUpdated 2 min read
The seven
| # | Have ready | Typically asked as |
|---|---|---|
| 4 | The window and why | "Why that period?" |
| 5 | The gap against platform numbers | "This is not what Meta says" |
| 6 | What would change your view | "What if you are wrong?" |
| 7 | The channels you could not measure | "What about X?" |
Five and six are the ones people fumble
Number five is asked in every meeting and answered well in almost none. The platforms will report higher figures because they credit conversions they touched under rules they set, and touches overlap between them. Bring the arithmetic: sum the platform claims for the window, divide by what the store actually took, show the ratio. That converts an awkward moment into the strongest part of your case. The method is in the claim ratio.
Number six is the credibility test. Have a specific answer: an interval that moved past a stated threshold, a holdout that came back differently, coverage falling below a floor. A vague answer here undoes the previous five.
The window question
Be able to say why you chose it in one sentence, and make the sentence about variation rather than convenience. "It contains the two spend changes we made in spring" is a good answer. "It was the last ninety days" invites the follow-up about whether another window would say something different.
If someone asks for a different window, run it. Refusing looks worse than any result.
Preparing seven in advance
Channels below the level of spend at which any method can separate an effect should be named as unmeasured rather than scored. Have that list ready, because someone will ask about their favourite small channel and the honest answer is stronger than an invented number. The arithmetic is in the measurability floor.
What to bring physically
The finance-facing framing is on pricing for the CFO conversation and the presentation structure in the attribution report a CFO will subscribe to.
Related answers
Frequently asked questions
What is the hardest question in an attribution meeting?
Two. Why your numbers differ from the ad platforms, and what would change your view. The first needs the claim ratio arithmetic prepared in advance; the second needs a specific, falsifiable answer rather than a vague one.How do I explain why my numbers differ from Meta?
Sum what every platform claims for the window and divide by what your store actually took. The excess is conversions claimed by more than one party, which is expected under platform rules and quantifies the overlap in euros.What if someone asks for a different time window?
Run it. Refusing looks worse than any result you might get, and a finding that holds across windows is considerably more persuasive than one defended by restricting which window is examined.
Go deeper: Causal attribution, explained.
Sixty-second versions of these ideas: Causality Engine on YouTube Shorts.
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Terms in this article
- Ad SpendAd Spend is the total amount invested in advertising campaigns. It is measured against Return on Ad Spend (ROAS) to evaluate campaign effectiveness.
- AttributionAttribution identifies user actions that contribute to a desired outcome and assigns value to each. It reveals which marketing touchpoints drive conversions.
- Attribution DebtAttribution debt is the gap between what your ad platforms claim drove revenue and what actually caused it, carried quarter after quarter into the budget. It is how marketing debt accrues: allocate on claimed conversions long enough and the plan itself becomes the liability.
- Attribution ReportAttribution Report shows which touchpoints or channels receive credit for a conversion. It identifies which campaigns drive desired actions.
- ConversionConversion is a specific, desired action a user takes in response to a marketing message, such as a purchase or a sign-up.
- IncrementalityIncrementality is the part of an outcome, such as orders or revenue, that a marketing activity caused: the extra results compared with what would have happened without it. It is a causal effect, not the number of conversions credited to a channel.