Is Incrementality Testing a Good Way of Validating Your Retargeting Campaigns?

How can incrementality testing help you?

Incrementality testing is a method of establishing what part of conversions is caused by the retargeting campaign and what portion is an aftereffect of the general marketing efforts of your brand. A difference between the two levels – positive or negative – is categorised as an incremental lift. Correctly performed incrementality testing is a helpful tool and can help you understand the impact of your retargeting campaign against other marketing actions.

The basics of incrementality tests

Even though incrementality testing can be performed in various ways, there are some basics that connect them all. The first step is accomplished by the client and retargeting provider when they determine the target group. Users who fit that group are divided by two, creating at the same time the test group and the control group. The users in the first group see ads delivered by the retargeting provider. On the other hand, ads displayed to the control group sees, are determined by standard retargeting and serve as a comparison.

Of course, it’s crucial to eliminate the risk of obtaining the results of incrementality testing due to randomness. That’s why testing should use a P-value, which defines the probability of variance and randomness influencing the results.

When your incrementality testing is done, you can see three types of results: no impact and negative or positive incremental lift. The first one means that there was no noteworthy difference between the groups. A negative incremental lift shows us that the test group behaved worse than the control group. The most sought-after result is a positive lift, which marks a successful retargeting.

What do you need before running an incrementality test?

Tracking the effect of your retargeting campaign is essential, but you should make sure that you’re able to perform incrementality tests in the correct way. Only then will the effort be worth it and the results reliable. How to maximise their value?

You’ll need an in-house analytics team that will be tasked with validating the results internally. Your experts should check whether the target groups were split correctly, examine conversion data, and see if the data from your retargeting partner checks out against your internal info.

The size of the retargeting campaign will influence the incrementality tests as well. A sample too small won’t be able to collect enough meaningful data for the analytics team. Another key factor is the timing of the testing. It shouldn’t be run from the start of the campaign, as retargeting needs some time to scale. Optimally, you may begin the testing after two or three months if the campaign is stable.