Jeff Sagarin's rating system is based on a mathematical formula that uses a player's won-lost-tied record against other players when they play on the same course on the same day, and the stroke differential between those players, then links all players to one another based on common opponents. The ratings give an indication of who is playing well over the past 52 weeks.
The following list is an explanation of each category Sagarin uses to formulate his rankings.
POWER RATING: This is NOT a stroke average. The rating is calculated using a player's record, stroke differential and connection to all the other players in the database. The difference between two ratings predicts the difference between two players in a typical round.
SCHEDULE STRENGTH: The average strength of each event in which the player has played, calculated using the power ratings of every player in every field.
SCHEDULE RANK: The player's schedule is ranked by difficulty among the entire database.
RECORDS: A player's won-lost-tied record, based on head-to-head competition, in each category. The winner in a 156-player field has a record of 155-0-0, the runner-up is 154-1-0, etc.
MEN -- 10 needed to qualify on nine worldwide tours: PGA Tour, PGA European Tour, Nationwide Tour, Japan Golf Tour, Southern Africa Tour, PGA Tour of AustralAsia, Asian PGA Tour, European Challenge Tour and the Canadian Tour.
WOMEN -- 10 needed to qualify on four worldwide tours: LPGA Tour, Ladies European Tour, Duramed FUTURES Tour and the Japan LPGA Tour.
BOYS & GIRLS A player must have played in five events in the rolling 52-week window (*-indicates player has not participated in the minimum number of events needed to be ranked).