Why timing is crucial for validating MMM through Experiments.

MMM (Marketing Mix Models) by virtue of being a larger and more complete representation of marketing reality, can be used to contextualize and sanity check experimentation.

However, this is only valid in a limited time window immediately after the model build.
At Aryma Labs, we call this window the umbra – typically the next 3 months post MMM.

But a experiment validation can still go wrong.

How?

Imagine you model a MMM for past 2 years (2024-25), Lets suppose your google ad spends have been most effective in the months Oct -Dec every year.

However, your model right now has the 3 months (Jan-March) in 2026 as the umbra.

If you were to conduct a incrementality test or Geo test to test Google ad spend effectiveness, chances are that you may not find statistical evidence for its effectiveness !!

And hence you may draw a wrong conclusion that MMM was wrong and that google spends didn’t work at all !!

It is hence important to monitor the contribution of all variables in MMM month over month or week over week. We do this for all clients and our tool ArymaEdge helps you slice and dice the contribution at any granularity.

This practice enables you to:

✅ Identify when a channel is structurally strong or weak.
✅ Choose the right windows for experimentation.
✅ Avoid false negatives in incrementality tests.

Feel free to schedule a demo or speak to us about MMM validation strategies: https://lnkd.in/gH7Bh7NJ