| Not myself (well one of the below applied to me at a brief point in my career), but here are cases I know of. Google, Facebook, and many others use mechanism design (which roughly counts as game theory) to design ad auctions which automatically run as users run searches and load pages. That must be the biggest application of game theory in running code. Auctions are popular applications of game theory in other places, particularly the FCC spectrum auction which involves running code. Game theory, of a kind, underlies "match" code that assigns medical residents to hospitals, and students to highschools in some school districts in the USA. Game theory has actually been used to design security schedules for 'national security' in places like airports and the Coast Guard -- this research was led by an effort at USC. Game theory is used in the design of prediction markets, which are often deployed within companies (though probably they don't need to do additional theory to deploy the markets to their application). There is a lot of crowdsourcing at scale going on in semi-automated systems, and a lot of research on game theory in crowdsourcing, but I don't know how much that research gets implemented. If Uber and Lyft aren't using a bit of game theory to set prices, and hopefully also think about incentives when assigning routes, then they're crazy. But perhaps they're using more "economics" than game theory. Game theory has been used to study social voting sites and "contests" like reddit, hackernews, stackoverflow, quora. However, I don't know if any of the designers of these sites are explicitly using game theory. |
The reason I'm interested in explicit implementations in code as opposed to theoretical narratives is because actual implementations have to deal with the not-so-nice cases in the real world, i.e. unaccounted-for interactions, stochasticity, flat-out incorrect conclusions, etc. (there are however some deterministic problem domains where the above aren't issues, and I'm curious to learn what these are). Every model is a simplification, but game theory models usually have less correspondence to reality than most hence my curiosity. Game Theory is often thought of to have broader applicability than it really has (due to hype). My interest is identifying those domains where game theory actually "works".