My grasp of probability is rudimentary (as Anesa knows), but I knew it was going to be tough to get a group of 5-8 students all to consent to have their data archived, when I was contacting 634 students divided into 110 groups. Despite a response rate of about 33% yesterday, I hadn’t managed it – but today members of one of the smaller groups have all consented. Hooray!

Of course, now I have to get their two tutors to agree – but I’m moving in the right direction.