HOW WRONG IS YOUR MARKETING MIX MODEL (MMM)?

Summary from the TLDR Marketing newsletter

MMM becomes more reliable when media budgets are deliberately phased, so channels move independently and spend reaches different levels. Build variation into the media plan by using tactics like weekly budget changes, dark periods, and peak spend periods instead of relying on model changes to solve weak data. In the simulation, the combined approach cut variance by 70% and bias by 47% while keeping each channel's annual budget unchanged. The tradeoff was a 3.42% loss in channel-driven revenue, so use lighter phasing when that cost is too high.