What is the probability that at least two people in a group of 20 people will have the same birthday? - David Franklin

But few of us really stop to ask ourselves what new information might change our minds, especially on questions of politics and identity. We fall into the trap of confirmation bias, in which rather than updating our prior beliefs, we mould new information into a form that will confirm them.

In Dan’s case, the interest in policymaking is so central to the students’ presence at Harvard that it would be foolish to run a statistics course that did not acknowledge it. He goes as far as to build this into the purpose of the course: as we heard earlier, his purpose is “not just to maximise learning about statistics, but also to maximise learning of the skills that will be useful to have out there in the world.

I guess… it was just a shocking event. We’re not used to someone like him being President.” Here, the student reveals an availability bias in which we expect future outcomes to look like what has gone before.