Matt's talk was titled "Clutching at Random Straws" and dealt with our innate tendency to detect patterns where none exist. His subjects included — amongst other delights — the deeply significant alignment of the ancient Woolworth civilisation, the explicable causal links between human birth-rate and preponderance of mobile-phone masts, and the likelihood of there being two or more people with the same birthday in any given group of people — such as those attending a Skeptics-in-the-Pub night.
The Q&A session was equally lively, and included Matt expounding his views on environmentalism and organic farming, as well as giving a quick rundown of the pros and cons of the Alternative Vote and First Past The Post voting systems (as follows, paraphrased):
Matt Parker is in the business of communicating mathematics, and we need more of his clear and direct style. He's available to lecture in schools and other places, as well as having a presence on the interwebs — as, for example, below:
If you're first past the post, it means you got the most votes. So let's say you've got four people who are running for an election — the person who gets the most votes might have 26% of the votes, and everyone else got just under 25. In which case they would get in on just 26% of people voting for them. So in fact 74% of people may adamantly not want them. And so that's kind of the thrust of this — you need a bigger vote than anyone else, but you don't need a bigger vote than everyone who's against you. And proportional voting is that if you vote for one of your guys, and it seems like they're not going to get in, you get to have a second choice, so your vote goes to the second choice, and if they're not going to get in, it goes to the third choice. You get to the final two people, and the person who is ranked higher more than the other person, gets in.
Say one guy was ranked above the other 52% of the time, and the other guy was ranked higher 48% of the time, that means 52% would rather have one than the other — more people for than against, rather than just more people for one than for the other. In an apolitical sense, I think AV is the fairer way to decide which candidate has the fewest people against them.