PDGA Ratings System Guide
The PDGA calculates round ratings for all sanctioned singles and league rounds where the TD has submitted the proper scores and course layouts. At this time, ratings are not calculated for doubles and team events, or in event formats that deviate too much from regular singles (some X-tiers). Ratings updates occur on the second Tuesday of each month and depending on an event's timing in relation to that schedule, and how quickly a Tournament Director (TD) submits their official report, it may take several updates for an event's official ratings to be calculated and posted. The TD will usually post scores online on the PDGA website during or after a tournament where players are able to see the unofficial ratings for rounds played. Typically the yearend final ratings for the previous year are posted in the February ratings update. The monthly ratings update schedule is shown here
A player’s PDGA rating is based on rounds in the 12 months prior to the date of their most recently rated round. If a player has less than 8 rounds, the system will go back up to 24 months until it either finds 8 total rounds, or it will just use all rounds if less than 8. All members should receive a rating even if they only have one rated round. Almost all rounds are counted. Rounds more than 2.5 standard deviations or more than 100 points below a player’s average are dropped (about 1 in 50). The most recent 25% (1/4) of rounds will count double once there are at least 8 round ratings. This makes a player’s recent performance a bit more important. If a player does not complete a round (score shown as 999), it will not be included in their ratings round count.
Your rating for each round is based on how well you shoot relative to a hypothetical scratch player defined as someone with a rating of 1000. The automated calculation uses scores from at least 5 players with ratings over 699 whose rating is based on at least 8 rounds of information. These players are called propagators. The ratings team uses a manual process to produce ratings when there are fewer than 5 or even no propagators.
The initial calculation step determines the Scratch Scoring Average (SSA) for each round. The SSA is the score a scratch player with a rating of 1000 would be expected to average on that course. For example, let’s say the SSA is calculated as 50 for an 18-hole course. Any player who shot a 50 that round would receive a rating of 1000 for that round. Each throw is worth about 10 rating points for courses with this level of difficulty. So, if you shot a 60, your rating for that round would be 900 because you were 10 throws worse than scratch, then mulitply times 10 points per throw. If you shot well scoring 48, your rating would be 1020 for that round which is 2 throws or 20 ratings points better than SSA. All scores thrown on the same course layout in multiple rounds will be used to determine the combined SSA and ratings except when wind is significantly different between rounds. Note that a course layout does not have a fixed SSA. It will vary based on the weather, season and tournament conditions.
The “10 ratings points per throw” holds up well on 18-hole courses with SSA values between 48-53. However, as a course gets much easier or much more difficult, the number of rating points per throw changes. In the case of a real easy course with an SSA around 44, every throw works out to about 13 rating points. On really tough courses like the USDGC with SSA about 68, every throw is about 6 rating points.
The reason that the ratings points per throw change over the range of course difficulties is an effect called “compression.” On a real easy course, top players can only shoot so well, given they are limited to scoring no better than a 2 on virtually every hole. However, on these courses, where the average hole is likely to be wide open and less than 250 feet, even lower rated players can also shoot lots of 2s. This "compresses" or narrows the range of scores for players of widely varying skills in that round. On the other hand, a really tough course with an SSA over 60 will spread the scores farther apart in each round when compared to a course with a scoring average of around 50 for scratch players.
Should you have any questions regarding the player and course rating system, or your own player rating, please first check the Ratings FAQs before contacting the PDGA Ratings team.