At the beginning of last year I wrote a paper for one way to set up an MMO economy. I started with the idea of a an economy where the NPC value (in gold) of items would vary depending on the available supply. As items became more common the price would go down and as they became more rare the price would go up. Eventually there would be something of an equilibrium point reached (at least in theory).
I figured that the shape of the value/demand graph should be a modified reciprocal curve. It’s not exactly the right shape but I figured it would be close enough. After the initial formula I decided I didn’t like what a few of the variables represented (maximum multiplier of the base price when available pool equals zero, for instance) so I swapped them out for formulas using easier to comprehend variables (maximum price, base price, etc.).
AÂ link to the paper (MS Word document) is available here. Re-reading it has started me thinking about trying to work out some way to set the values of a lot of the variables automatically over time, so I guess I’ll have to explore that some time.