Do you mean the Email Send (mailbox) Program?
Random Sample will only work with Choice Steps, which you cannot use in this type of Program. If you want to send emails to randomly selected groups, use an Email Blast Program and a campaign:
Choice 1: Random Sample IS 50, then send Email B
Default: Send Email A
You can also generate static lists like this.
- create campaign,
- select overall group
- Add to List with Random Sample (must have lists already)
- Run campaign
- use lists in Send Email Choice Steps.
You can also use A/B tests with the email (mailbox) programs, which gives you a wide assortment of testing options. You can test up to 10 different subject lines, different emails and sender details. You can enable Marketo to automatically choose a winner or notify you with the results from a test so you can choose the winner. Depending on how you're using the random sample, these A/B tests features are much more robust and easy to use.
The A/B testing can only test Subject line, Whole email, From address, Date/time. How about I want to test both subject line and email content? I assume that test "whole email" can achieve my goal. But isn't it still hard to fine out which combination test will be better?