Professor Ben Polak: Okay, so last time we looked at and played this game.
You had to choose grades, so you had to choose Alpha and Beta, and this table told us what outcome would arise.
In particular, what grade you would get and what grade your pair would get.
So, for example, if you had chosen Beta and your pair had chosen Alpha, then you would get a C and your pair would get an A. One of the first things we pointed out, is that this is not quite a game yet.
It's missing something.
This has outcomes in it, it's an outcome matrix, but it isn't a game, because for a game we need to know payoffs.
Then we looked at some possible payoffs, and now it is a game.
So this is a game, just to give you some more jargon, this is a normal-form game.
And here we've assumed the payoffs are those that arise if players only care about their own grades, which I think was true for a lot of you.
It wasn't true for the gentleman who's sitting there now, but it was true for a lot of people.
