Rico Stuijt is the incrementality lead at online food delivery platform Just Eat Takeaway.com. In this nearly one-of-a-kind role, he leads the direction, strategy, and implementation of testing across the company’s performance marketing channels.
As you can imagine, at Just Eat Takeaway.com we think about food a lot, so think of incrementality testing like your favourite dish. With incrementality testing you make the same dish multiple times but always leave one of the ingredients out. You're trying to figure out which ingredients are adding which flavour. You could guess, but with incremental testing you don’t need to.
It's like a science experiment for marketing. We take two groups of people — one that sees our ads (the "test" group) and one that doesn't (the "control" group). Then, we compare their behaviour to see if our ads actually made a difference.
This helps answer two major questions. First, are our marketing efforts truly driving extra orders and new customers, or are we just taking credit for things that would have happened anyway? And second, what optimisations should we experiment with to further increase the impact of the channel on the business?
Through this testing I 've found the perfect ingredients for success: a chef and their recipes.
Appoint a chef for your modern measurement framework
My journey with incrementality started almost a decade ago, back when I was focused on affiliate marketing at Just Eat Takeaway.com. I noticed something odd: discount voucher publishers were getting all the credit for orders, even though customers were clearly already in our checkout process when they searched for a discount code. Traditional attribution models were giving us a distorted view of reality.
That's when I started experimenting with ways to ensure the credit for conversions was going to the right places. It was a basic form of incrementality measurement, before I even knew what it was called.
At Just Eat Takeway.com, our measurement framework includes attribution, MMM, and incrementality. Think of me as the chef of our incrementality framework. I design the recipes, establish the methodologies, and ensure we're using the right tools and techniques. This includes defining our incrementality measurement approach using a combination of geo-lift tests (where you compare regions where you do, and do not run your ads), conversion lift tests, and a central control group methodology.
I work closely with specialists and marketers across different channels to educate them about incrementality and empower them to run their own tests. It's about shifting mindsets and encouraging everyone to embrace a data-driven approach.
We run conversion lift tests on different accounts across most markets every four months, totalling 200+ tests in 2024 alone. You can imagine the amount of data that creates! I analyse this data to identify key trends, uncover hidden opportunities, and ultimately drive more effective marketing decisions to improve channel effectiveness.
Mix in a recipe designed for your goals
“Although having an incrementality chef is a great step and demonstrates the mandate from leadership to focus on incrementality, that alone is not enough,” says Jakob Biebuyck, experiments specialist for Google Northern Europe. “Next to having the mandate, there also needs to be processes in place on how experiments will lead to performance gains.”
The recipe for success is not just about how, but also who. This means you need both strategic leadership (the "chef") and a sound methodology (the "recipe").
But that’s not all. “The goal of incrementality testing isn't just to prove value, but to improve it, and that takes a slightly different setup because you don't want to do one test every six months but you need to do it very regularly,” Biebuyck continues.
He says that for the most part there will be four key ingredients, or areas of optimisation, for incrementality tests: budget, bidding, targeting, and creative. Every quarter a focus area for experimentation is decided on — a hypothesis is set, the experiment is designed, and after the experiment is over, the learnings are analysed to make sure best performance is implemented. “And then we continue on our next quest,” he concludes.
This methodology results in an iterative process, continuously optimising and building on previous learnings. You can imagine creative optimisations lead to increased performance, so you’d like to follow this experiment with another budget experiment to make sure we are growing as much as we can profitably. We see that this continuous process is what sets up the most advanced and mature advertisers for delivering optimal performance.
How incrementality (and Just Eat Takeaway.com) delivers
In the world of Just Eat Takeaway.com, customers make quick decisions based on a wide set of variables. For example: immediate needs (they're hungry), the weather (they don’t want to go out for groceries), or social situations (having a quick bite before a meeting). This variety of influencing factors means that broad marketing activations and traditional attribution models can fall short. They can't capture the contribution of each channel and so they can't accurately measure the true impact of our marketing efforts.
Incrementality, on the other hand, allows us to isolate the causal effect of our campaigns by having a control group, and understand which activities are truly driving incremental orders and new customer acquisition.
The proof is in the pudding. By embracing incrementality and the iterative test and learn methodology, we've seen an over 60% increase in channel effectiveness in just two rounds of testing. That means more orders and new customers for the same budget. We're now able to identify and invest in the channels and campaigns that truly move the needle for our business, both in the short-term and the long-term.
“Our teams at JET have gone through a tremendous mindset shift to focus on what is driving incremental performance, rather than relying purely on attribution,” says Yiğit Yazgı, Global Manager Performance Marketing Measurement. “This has created a strategic advantage for Just Eat Takeaway.com, as we are not only able to see what works, but also why it works, by systemically learning and improving with our test-and-learn agendas. We are a business that operates in a highly competitive space, so we test to answer the most important business questions at the time, and learn what actions to take. Our marketing has always been data-driven, and today it is more impactful than ever, thanks to setting the context with the effectiveness mindset.”
If you're still wondering how incrementality testing helped us achieve this, there are several factors. Firstly, the rigorous testing and analysis of our marketing activities meant we were able to identify and eliminate wasteful spending. For example, if a channel was not driving results, we reallocated budget to more effective channels.
It also allowed us to optimise campaigns for maximum impact by giving us granular insights into which campaign elements were driving the most conversions. This allowed us to fine-tune our targeting, messaging, and creatives for optimal performance.
If there's one thing I want you to take away from this, it's this. Begin your incrementality journey today, even if it's just a small step. You'll be amazed at the insights you uncover and the impact it can have on your business.
