If you scale Meta and Performance Max in lockstep, even a well-built MMM can't tell them apart. Here's why channel correlation kills measurement accuracy - and what to do about it.
Earned media that isn't flagged as a control variable in your MMM gets attributed to whatever paid channels were running at the same time. Here's how invisible signals corrupt your model.
When measurement vendors work in isolation from the media agency, critical account context goes missing and the recommendations suffer for it. The best MMM setups are a three-way collaboration.