What is Adjusted Strokes Gained?

Adjusted Strokes Gained measures how many strokes better or worse a golfer performed compared to an average championship-level player, after accounting for course difficulty and playing conditions. For example, if you shoot 68 in a round where an average player is estimated to have scored 74.5, your Adjusted Strokes Gained for that round would be +6.5. A positive value means you outperformed the field; a negative value means you were below average.

What does "Time-Weighted" mean?

More recent rounds carry more weight in the ranking calculation. An exponential decay function is applied so that recent form is valued more heavily than older results.

• Yesterday — 1.00
• 1 month ago — 0.91
• 3 months ago — 0.76
• 6 months ago — 0.58
• 12 months ago — 0.33
• 24 months ago — 0.11

How many rounds are required to qualify?

A minimum number of rounds within the lookback window (currently 2 years) is required to appear in the rankings. For the men's rankings, 20 rounds are required; for the women's rankings, 10 rounds are required.

Which events are included?

Only amateur events staged in Ireland and sanctioned by Golf Ireland are included — such as provincial championships, scratch cups, and national events. Overseas events are not counted, even if played by Irish golfers. International events staged in Ireland by organisations such as The R&A, EGA, or other international bodies are also excluded. The Interprovincial Championships are not included in the rankings.

How does strength of field affect the rankings?

The model adjusts each round for the strength of the field by estimating course and condition difficulty from the scores of all players in that round. Performing well in a strong field naturally produces a higher Adjusted Strokes Gained because the baseline "average" score is lower when better players are competing. In other words, a good score against tougher opponents is worth more than the same score against a weaker field.

How are match play events handled?

Match play doesn't produce a score, so the system creates an artificial Adjusted Strokes Gained for each match based on the result. First, the average rating of all rated players in that round is calculated. Winners are then assigned that average plus a fixed margin, and losers get the average minus the same margin. A player needs at least 5 strokeplay rounds on record before their match play results count.

How are withdrawals and no-returns handled?

Where a player withdraws or records a no-return, their score for that round is set to the average score for that round plus 6 strokes. They still receive a poor Adjusted Strokes Gained, but the penalty is consistent and doesn't distort their overall rating.

Strokeplay: Round 2 (19 April, Co. Sligo)

The model estimated a baseline score of 77.3 for Round 2 at Rosses Point — this represents the expected score for an average championship-level player on that course in those conditions. That day was relatively calm compared to Round 1 (which had a baseline of 82.3), so the bar was lower.

A player who shot 75 (+4) in Round 2 would receive an Adjusted Strokes Gained of:

77.3 − 75 = +2.3 ASG

In other words, they performed 2.3 strokes better than the average championship player would have in the same conditions. A score of 80 in the same round would yield 77.3 − 80 = −2.7 ASG, meaning 2.7 strokes worse than average.

Match Play: Quarter-Finals (20 April)

Eight players contested the Quarter-finals: Holmes, Keane, Anderson, Egan, Grehan, Fox, Campbell, and Gillivan. The average strokeplay-based rating across all eight was +3.1 — a strong field. With a match margin of 2.0:

Winners: 3.1 + 2.0 = +5.1 ASG
Losers: 3.1 − 2.0 = +1.1 ASG

Note that even the losers received a positive ASG for that round — because the field was so strong, losing a Quarter-final at the West still reflects above-average play.

Contact

For data queries or event-related enquiries: ratingsqueries@quantumsportsdata.com