Using Math To Tune a Video Game's Economy

An anonymous reader writes: When the shipping deadline was approaching for The Witcher 3, designer Matthew Steinke knew there was a big part of the game still missing: its economy. A game's economy is one of the things that can make or break immersion — you want collection and rewards to feel progressive and meaningful. Making items too expensive gives the game a grindy feel, while making them too cheap makes progression trivial. At the Game Developers Conference underway in Germany, Steinke explained his solution.

"Steinke created a formula that calculated attributes like how much damage, defense, or healing that each item provided, and he placed them into an overall combat rating could be used to rank other items in the system. ... Steinke set about blending the sub-categories into nine generalized categories, allowing him to determine the final weighting for damage and the range of prices for each item. To test if it all worked, he used polynomial least squares (a form of mathematical statistics) to chart each category's price progression. The resultant curve (pictured below) showed the rate at which spending was increasing as the quality of each item approached the category's ceiling value."

Comments

Bad Example

[Carewolf]

The economy is one of the very few real weak points of Witcher 3. The article doesn't explain in detail what he did, but whatever it was: Don't do that, unless you have an otherwise master-class game to outweigh your mistake.

Re:Bad Example

[crashumbc]

Yeah, I felt the the economy is witcher 3 one of the few bad points of the game

Witcher 3's "economy" basically consisted of kill shit, get extreme amount of loot, sell loot, have thousands of needed coins at end of game....

Re:Oh noes, not MATH?!

[Dutch Gun]

I'm exaggerating a bit, as I was going for a humorous remark. So, killing the joke dead and answering your question seriously, yes, I've heard of Eve Online, and know quite a bit about it, but haven't played it. In terms of economies and designer math skills, MMOs are a slight exception. They take their in-game economies very seriously, and some are known to hire actual economists to help guide their virtual trade and monetary policies.

Designers don't necessarily avoid math, but they often use it in ways that drives programmers insane. For instance, they'll use formulas in spreadsheets to calculate tables of figures for loot, armor, damage, etc, and then painstakingly enter all those figures by hand. Why? This allows them the freedom to individually tweak components as desired. Programmers look at this and shake their heads, because we're hardwired to avoid that sort of redundancy whenever possible. For whatever reasons, some designers seem to revel in it.

Many designers tend to be control freaks. They're deathly afraid of automatic, feedback driven, or chaotic systems (all of which could apply to an economy), and often for good reason, as some outlier condition could tend to cause autonomous systems to spiral out of control. This is why most MMO in-world "economies" are tightly controlled affairs, with lots of limiters to prevent things from going too far in any particular direction too quickly. Programmers are always suggesting ways to create automatic and chaotic environments driven by algorithms, but designers want carefully scripted and planned systems, because they want to control and tweak it.

From the description, it appears this designer only turned to math as a last resort, because there was simply no time to do the sort of hand-tweaking that designers typically do. They were impressed enough with the results (gosh, math actually works!) that they wrote about how they did it. And the programmers on the team are probably thinking "I told you so. In fact, I told you so years ago, and you only listened to me when your back was up against a wall."