Depending on where you live the Sony PlayStation4 is either available or will be soon. Microsoft's Xbox One will follow shortly. Reviewers argue over which is best in terms of graphics, controller and the like, but the general consensus seems to be that they are pretty similar. They are not, however, similar in price! The PlayStation4 is around $100 cheaper than the Xbox. Of course, making like for like comparisons on price is difficult because Microsoft are offering things Sony are not and vice-versa. But, even so it is interesting to explore why Sony might want to come in with a lower price. Let's start by supposing Sony has a monopoly - they are the only games console maker. Sony has to set a price to sell the console and a price to sell games. In the parlance of micro theory this is a two part tariff where the console is a fixed cost and the games are a user cost. To make the most money Sony should set the price of games equal to marginal cost...
Some random thoughts on game theory, behavioural economics, and human behaviour