A game lader is a series of ranking levels used to measure playing skill in competitive games. Game ladders are an integral part of the playing experience for many games. The most widely known system of ranking players is the ELO rating system, which is used for Chess and Go. Every player in the ELO rating system receives a rating based on his or her win/loss record, which establishes his or her position (or level) on the game ladder. Numerous efforts have been made to design better game ladders by analyzing the statistical correlation between relative ladder levels and a player's expected performance.