Portsmouth FC scores shown first. Bivariate Poisson with team xG from recent form — most-likely score ≠ most-likely winner.
Probabilities derived from a Poisson model on expected goals. Edge % shown only when the book posts both sides of a market.
Joint probability comes from the score grid (the truth). Naïve is what a book gets by multiplying legs — they undershoot correlated positive legs like "home + BTTS" and overshoot anti-correlated ones like "draw + over 2.5". Buy positive correlation; avoid negative.
Model probabilities Portsmouth FC 40.7% · Draw 24.3% · Swansea City AFC 35.1% Why Portsmouth FC is favoured Swansea City AFC's Elo (1510) is +28 over Portsmouth FC (1482); low confidence. Recent: Portsmouth FC 4W-4D-2L · Swansea City AFC 6W-1D-3L (last 10). Goal differential per game: Portsmouth FC +0.2, Swansea City AFC +0.3. Form depth Portsmouth FC: avg 1.1 goals scored, 0.9 conceded per game (3/5 at home, 1/5 on the road). Swansea City AFC: avg 1.5 goals scored, 1.2 conceded per game (4/6 at home, 2/4 on the road). Goals expectation Model expects ~2.3 total goals (Portsmouth FC 1.1, Swansea City AFC 1.2) — right around 2.5. But — counter-arguments Swansea City AFC has a stronger recent record (60% vs 40%) — model favours Portsmouth FC on Elo + home advantage despite the form gap. Elo confidence is low (15%) — ratings are based on a thin sample, so the prediction itself is wider than the headline number suggests. Head-to-head 2 prior meetings — Portsmouth FC 0W, 2D, Swansea City AFC 0W (draws are common). Last 3: 1-2, 1-0, 4-0. Calibration Raw model: 42.6% home · Platt-calibrated down to 40.7% based on historical reliability across this sport's graded matches. Confidence note Elo data on these teams is thin (15% sample-size confidence); this is a low-conviction match overall — bet only with strong reason from outside the model.