Open-source Media Mix Modeling (MMM) tools are everywhere right now. Between Meta’s Robyn, Google’s Meridian, and PyMC Labs’ PyMC-MMM, it’s never been easier to get your hands on powerful modeling frameworks—a welcome unlock for MMM practitioners. But here’s the catch: the tools alone aren’t enough. To unlock real business value, you need more than just code—you need deep marketing and modeling expertise.
The most effective MMMs don’t rely on tech or talent alone. The real power lies in the combination of the two: smart tools paired with experienced partners who know how to structure the data, tune the model, validate the results, and most importantly, turn insights into actions with results. Let’s break down a few common myths about open-source MMMs, and why the right partner can make all the difference.
Myth #1: Anyone Can Run an MMM With Open-Source Tools
Reality: Your model is only as good as the expertise behind it.
Open-source models give you the framework and code but making sense of the math and how it fits your business takes real data science expertise. Building a reliable, business-ready MMM isn’t just data science work—it’s a complex cross-functional marketing analytics project. You need:
- Rigorous data engineering to clean and organize data across platforms, channels, and geographies
- Deep media and marketing expertise to understand how media actually impacts business results over time
- Strategic flexibility to make the right modeling choices based on how media works for your business
Most importantly, you need to know when your data isn’t telling the full story—undermining the true story. Open-source MMMs won’t warn you about data discrepancies or misalignment going into the model. The results may look polished, but without careful quality checks to ensure data accuracy, your results won’t be reliable.
MMM success starts with getting the foundations right—otherwise you’re building your marketing strategy on sand. It is recommended to look for partners that can facilitate integrated data and modeling.
Myth #2: The Model Does the Hard Part
Reality: The heavy lifting happens before and after the code runs.
It’s easy to generate numbers—but it’s hard to generate the right ones. Open-source packages aren’t full solutions; they’re frameworks. They don’t automatically validate your data, guide your assumptions, or warn you when something is off. You’re responsible for decisions like:
- Which modeling paradigm to use (Frequentist and/or Bayesian)
- How to discover and tune adstock and saturation curves for each channel
- What non marketing variables to include—or how to feature engineer them
- How to capture seasonality, trends, holidays, price and promo impacts
These decisions aren’t minor technicalities—they make or break your model. They require judgement, strategic context, and real-world understanding of how your specific business operates.
And then there’s the tech side of things. Open-source MMMs often need very specific environments, managing tricky software dependencies, or powerful computing to avoid long run times. The frequency of MMM reruns adds another layer to the complexity of overall MMM management. Without the right setup and know-how to troubleshoot, even free tools can end up costing you time, headaches, and mistakes.
Myth #3: Insights = Action
Reality: Models don’t drive growth—people do.
Even a well-built model falls flat if it doesn’t lead to action. And that’s often where harnessing open-source solutions stalls. Because a model can’t:
- Translate results into strategic media and budget decisions
- Align marketing, finance, and leadership teams
- Scenario-plan with confidence, not guesswork
Some open-source frameworks do offer budget allocators that can support strategic decisions—but they still need an expert in the loop. Most open-source tools stop at the MMM output. A strong partner goes further—turning insights into impact. This is where marketing technology platforms serviced alongside human expertise can be super powerful
So, Does an MMM Partner Still Matter?
Absolutely—especially if you don’t have the resources to build and use it effectively in-house. The right MMM partner will:
- Build custom modeling that reflects your unique business and media mix
- Ensure your data is clean, accurate and trustworthy
- Translate MMM results into executable strategies
- Measure how the strategies are working
- Enable you to build trust in the numbers—and marketing—across your organization
In short, they transform the open-source solutions into the exact MMM that your business needs—faster, with more clarity, and far less burden on your internal teams. Because the goal isn’t to build a model. It’s to build confidence in your next move.
Don’t know where to start? Connect with our measurement experts to figure out the right MMM solution for your business.
