Can I measure incrementality on Facebook?
Yes, Incrementality of incremental contribution of Facebook advertising towards sales or other business outcomes can be measured. The approaches used for this purpose are called advanced marketing measurement techniques.
The most commonly used advanced marketing measurement technique for measuring incrementality on Facebook is called Design of Experiments (DoE).
DoE, when expertly designed, has the ability to deliver on the promise of incrementality measurement at the campaign, audience and ad set level in a way that MMM cannot due to practical limits on data granularity and degrees of freedom and MTA cannot due to the aforementioned limitations on user level impression data. DoEs carefully select a subset of users to serve as the control group, showing them a PSA advertisement usually for a charity of the marketers choice in order to determine the true incrementality of Facebook impressions. A carefully designed Facebook DoE can go into much more detail than simply channel level incrementality and instead can execute always-on simultaneous experimentation at the campaign, audience and ad set level with the only limitations being the number of days required to achieve statistical significance which is driven by reach at campaign/audience/adset level. For most mid-market advertisers as scale this statistical significance is achieved in a matter of weeks, and can be meaningfully updated afterwards on a weekly basis and be used to inform tactical campaign optimization at the weekly level.