In Sitecore Personalize, why is a control group is not being created automatically when I create a variant?

Question

When setting up an AB test in Sitecore Personalize, I can create a variant but there is no automatic control group getting created.

Answer 1

If a control group is not being automatically created when you create a variant, this means you have setup an experience instead of an experiment. If you want to run an AB test with a control group you should set up an experiment.

Experiments are for running AB tests, in which a variant is compared against a control group. Experiences are for always on personalisation or operational use cases.

In practical terms, when an experiment is created:

• a control group is automatically created by the platform
• the sample size can be calculated in the details tab, this sample size is used to determine when the experiment is complete and the performance results can be interpreted.

When an experience is created:

• there is no control group automatically created
• there is no sample size to be calculated as there is no test running