Definition
Also written: MMM, media mix modelling
Marketing mix modelling uses aggregate historical data — spend, sales, seasonality, price, external factors — to estimate each channel’s contribution statistically. Because it works on aggregates rather than individual journeys, it is unaffected by cookie loss and consent restrictions.
It has become more prominent as user-level tracking degraded, and it complements incrementality testing: MMM estimates contribution broadly, experiments validate specific claims.
It needs history — typically two or more years of reasonably varied spend. A channel whose budget never changed cannot have its effect separated from the baseline.
The usual error
Where this goes wrong in practice
Commissioning one for a business without enough spend variation. The model will return coefficients, and they will not mean anything.
Related terms
Incrementality testing
Incrementality testing measures what a marketing activity actually caused, by comparing a group exposed to it against a comparable group that was not. Geographic holdouts, audience splits and time-based tests are the common designs, and the output is a causal estimate rather than an attributed share.
DefinitionMulti-touch attribution (MTA)
Multi-touch attribution distributes credit for a conversion across the marketing touchpoints that preceded it, using a rule (first touch, last touch, linear, time decay) or a data-driven model. It describes observed sequence; it does not establish that any touchpoint caused the outcome.
DefinitionConsent mode
Consent mode is Google’s mechanism for adjusting tag behaviour according to a visitor’s consent choices, sending cookieless pings when consent is denied so that conversions can be modelled rather than simply lost. Its output is estimated, and reporting distinguishes observed from modelled data.
DefinitionGA4 key events
Key events are the GA4 events a property has marked as significant — the renamed successor to "conversions" in that interface. They drive reporting and can be imported into advertising platforms, and their counts may include modelled as well as observed data.
DefinitionOffline conversion import
Offline conversion import sends outcomes that happen outside the website — a qualified lead, a booked job, closed revenue — back to the advertising platform, matched to the original click. It lets bidding optimise toward revenue rather than form fills.
DefinitionPerformance Max (PMax)
Performance Max is a Google Ads campaign type that serves across Search, Display, YouTube, Discover, Gmail and Maps from one budget, with placement, audience and creative decisions automated. It reports far less channel-level detail than the campaign types it replaced.
Definition