1. Deild · Friday, 21 August 2026. Final score 1–3 (half-time 0–2). Rebuilt from the season as it stood that morning, our rating would have been 71% for over 2.5 goals. This match is older than our frozen ratings ledger, which keeps 30 days, so that figure is a reconstruction from pre-match data rather than a number we published at the time — a distinction worth making, because only the frozen ones prove what we actually said beforehand.
Open this match in the app →| Market | Yes | No | Our call |
|---|---|---|---|
| Over 2.5 goals | 71% | 29% | Over |
| Over 3.5 goals | 46% | 54% | Over |
| Both teams to score | 71% | 29% | Yes |
The result model puts Grotta at 44%, the draw at 22% and IR Reykjavik at 34%, from expected goals of 1.95 and 1.71.
The league sets the starting point. 1. Deild has produced over 2.5 goals in 70% of its matches, and that is where a team with no record of its own would sit.
Each side's own record. Grotta have 14 in 18 this season (8 of 9 at home), IR Reykjavik 13 in 19 (7 of 9 away). Those records are pulled toward the league rate with the weight of about 24 matches — enough that two or three unusual games cannot swing a rating — giving 73% and 69%.
Last season still counts, briefly. With 18 and 19 games played this season, last season's rates are still blended in and fade out entirely by game 40 — the point at which our testing showed they stop adding accuracy. A single season is part luck, so each club's record is first pulled toward the league average by 34 games' weight. That moves the two figures to 73% and 66%.
The mix. Weighted 40% home side, 40% away side and 20% league — the split that beat every alternative across 30,582 matches of testing — that gives 70%.
Head to head. These sides have met 3 times in three years, producing over 2.5 goals in 100%. That nudges the number 5% of the way toward the head-to-head pattern — deliberately small, because fixtures change more than reputations do — landing on 71%.
Goal expectation. Separately a Poisson model built from attack and defence strength — using real expected-goals data where the league has it — puts this match at 71%, from expected goals of 1.95 for Grotta and 1.71 for IR Reykjavik. Folding in 30% of that view gives 71%.
This breakdown is generated from the same inputs the rating uses, so it cannot describe a calculation we did not perform. The full model is set out in the methodology.
| Team | Games | O2.5 | O3.5 | BTTS |
|---|---|---|---|---|
| Grotta | 18 | 78% | 44% | 78% |
| IR Reykjavik | 19 | 68% | 53% | 74% |
More: Grotta season stats · IR Reykjavik season stats · 1. Deild table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.