Results of Journey Builder Random Split Didn't Distribute as Expected

If the Random Split didn’t distribute evenly based on the expected percentages, it’s due to the small number of Contacts.
 

If a small number of Contacts are evaluated there aren’t enough records to give a true distribution according to the probability selected. The results of the previous contacts have no effect on the next contact.


Within the Marketing Cloud May Release, Journey Builder released a new feature called the Path Optimizer that can also be considered for split testing in the Marketing Cloud. Note, the same logic applies to Path Optimizer. If you are not seeing the expected distribution, increase your sample size.

• Feature Notes

Example

If you have a random split of 80%-20%, and inject one Contact, it's more likely that it will be placed on the 80% branch. If you inject 10 Contacts, each of those individual Contacts have an 80% chance of being placed on that branch. With such a small sample size, it's possible that more than eight of the Contacts will be placed on that branch. If you were to inject 10,000 contacts, it's more likely that the distribution will be closer to the 80%/20% split.