...
- The invitation should be from a person or organization they know (and preferably have a relationship with), as discussed in “Who should send the email?” earlier.
- The basic pitch should be clear at a glance.
If this is a web ad, the ad text needs to convey the basic proposition. If this is an email invitation, the subject line must perform this duty. - The person’s most immediate questions must be answered by skimming the invitation.
Not only do you need to answer basic questions (How long will this take? What do I get in return?), but you need to do it in a way that a busy, only slightly interested person will absorb. - It should sound like something they're familar with, so call it a "survey".
As we mentioned in Using web ads earlier in this chapter, the term "tree test" is unfamiliar, so use the much more familiar "survey". - There must be a clear way to start the study.
This seems obvious, but we’ve seen lots of invitations that included so many other links (to more information, terms and conditions, privacy statements, etc.) that it took some effort to figure out which link was for the study itself.
...