Foursquare’s database currently includes 60 million venues, and the company today decided to explain how it is maintained. More specifically, Foursquare has outlined how it rewards and punishes the superusers who sift through the constant updates of hours, locations, and phone numbers that are submitted from users all around the world.
In short, Foursquare works similarly to other existing crowd-sourced datasets (Quora, Stack Overflow, Amazon Reviews): it assigns superusers points based on their tenure, reputation, and the actions they take. Diligent superusers are rewarded and malicious superusers are punished, and Foursquare uses complex formulas to make guarantees about the accuracy of its database.
➤ The Mathematics of Gamification (Foursquare Engineering Blog)