As we think about emailing newcomers, we know that we can only email them if they have a verified email address and if they have opted-in to receiving these emails. As a useful benchmark, we could look at:
Newcomers who have a verified email AND who responded on the welcome survey that they are interested in receiving contact from mentor.
We need to see this separately for Korean and Czech, amongst just those newcomers who were in the treatment group for the welcome survey.