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2025-2026 GLEAGUE Model Performance Analysis

Scope

All scored games in the selected league and season. AP Poll is excluded here.

Comparing prediction accuracy across 543 games using multiple rating models.

Model Catalog

7-day holdout coverage: 16/17 models .

Rolling Holdout Curves

Each point is a strict weekly holdout: train on all games before that week, test on that week. This first version uses a 21-day warmup, then 7-day holdouts stepped forward weekly.

Log Loss Brier AUC Accuracy

Weekly strict holdout log loss. Lower is better. Showing 16 models across 22 windows. Click legend items to hide/show series.

Recent Window Winners

Holdout Best Log Loss Runner-up Models
Apr 8 - Apr 10 Log Adjusted 0.567 Adjusted Efficiency (0.568) 16
Apr 1 - Apr 7 Log Adjusted 0.563 Adjusted Efficiency (0.563) 16
Mar 25 - Mar 31 Home Team Baseline 0.650 Points Off/Def Recency (0.669) 16
Mar 18 - Mar 24 Dynamic Bradley-Terry 0.674 Bradley-Terry (0.676) 16
Mar 11 - Mar 17 Home Team Baseline 0.601 Points Off/Def (0.715) 16
Mar 4 - Mar 10 Pythagorean 0.624 Avg Margin Baseline (0.633) 16
Feb 25 - Mar 3 Dynamic Bradley-Terry 0.591 Elo (0.601) 16
Feb 18 - Feb 24 Points Off/Def Recency 0.692 Margin Recency (0.695) 16

Model Performance Leaderboard

Models ranked by strict holdout AUC when available (fallback: full-season AUC). Hover over column headers for explanations.

# Model 7d Split AUC Acc Brier LogLoss n AUC 7d Acc 7d Brier 7d n 7d
1 Pythagorean Pythagorean Pythagorean win expectation from raw points scored and allowed. More → STRICT
4g
0.532 53.4% 0.265 0.731 756 0.667 75.0% 0.243 4
2 Adjusted Efficiency Adjusted Efficiency Opponent-adjusted efficiency model with separate offensive and defensive components. More → STRICT
4g
0.541 53.0% 0.301 0.861 756 0.667 75.0% 0.227 4
3 Log Adjusted Log Adjusted Log-scale adjusted efficiency model that downweights blowout leverage. More → STRICT
4g
0.541 53.0% 0.301 0.861 756 0.667 75.0% 0.227 4
4 Avg Margin Baseline Avg Margin Baseline Predict from simple average scoring margin in the training window. More → STRICT
4g
0.686 64.3% 0.223 0.637 756 0.667 75.0% 0.231 4
5 Efficiency Efficiency Tempo-adjusted efficiency version of Pythagorean ratings. More → FULL
no 7d
0.518 53.6% 0.350 1.121 661 - - - 0
6 Margin Margin Linear team-strength model fit on point differential instead of binary wins. More → STRICT
4g
0.474 47.9% 0.286 0.775 756 0.333 50.0% 0.249 4
7 Points Off/Def Points Off/Def Raw points regression with separate offensive and defensive team parameters. More → STRICT
4g
0.521 52.2% 0.291 0.802 756 0.333 50.0% 0.249 4
8 Home Team Baseline Home Team Baseline Always favor the home team with a fixed prior. More → STRICT
4g
0.539 54.0% 0.252 0.697 756 0.167 25.0% 0.310 4
9 Elo Elo Streaming paired-comparison rating with recency baked into sequential updates. More → STRICT
4g
0.544 52.4% 0.252 0.698 756 0.000 0.0% 0.375 4
10 Bradley-Terry Bradley-Terry Static logistic paired-comparison model with one team strength parameter. More → STRICT
4g
0.486 48.4% 0.273 0.745 756 0.000 25.0% 0.272 4
11 Bradley-Terry Recency Bradley-Terry Recency Static Bradley-Terry with exponential recency weights on newer games. More → STRICT
4g
- - - - 0 0.000 0.0% 0.367 4
12 Margin Recency Margin Recency Margin regression with exponential recency weights on newer games. More → STRICT
4g
- - - - 0 0.000 25.0% 0.296 4
13 Points Off/Def Recency Points Off/Def Recency Off/def points regression with exponential recency weights. More → STRICT
4g
- - - - 0 0.000 25.0% 0.293 4
14 Core Ensemble Core Ensemble Equal-logit blend of Elo, recency BT, recency margin, log-adjusted pyth, and points off/def. More → STRICT
4g
- - - - 0 0.000 25.0% 0.299 4
15 Recency Ensemble Recency Ensemble Equal-logit blend of Elo, recency BT, recency margin, log-adjusted pyth, and recency points off/def. More → STRICT
4g
- - - - 0 0.000 25.0% 0.309 4
16 Dynamic Bradley-Terry Dynamic Bradley-Terry Time-evolving paired-comparison model with latent team strength drift. More → STRICT
4g
- - - - 0 0.000 0.0% 0.332 4
17 Adjusted Context Blend Adjusted Context Blend Experimental context-heavy win model blending strong team components with rest and venue context. More → STRICT
4g
- - - - 0 0.000 25.0% 0.299 4

Methodology

ELO / Bradley-Terry

  • ELO: Iterative updates, K=64, HCA=100
  • BT: Static logistic regression on all games
  • Both model win probability, not margin
  • ELO updates after each game; BT fits once

Pythagorean Models

  • Raw: Classic points scored/allowed formula
  • Efficiency: Pace-adjusted (pts per possession)
  • Adjusted: Opponent-adjusted efficiency
  • Log: Log-linear multiplicative scale

Margin Regression

  • Team-level ridge regression on point margin
  • Linear Bradley-Terry (margin target)
  • Alpha=0.05 (CV-tuned)
  • Learns home advantage from data (~6 pts)

Baselines

  • Home Team: Always predict home wins (60%)
  • Avg Margin: Higher average margin wins
  • Models should beat these to add value