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2025-2026 NBA Model Performance Analysis

Comparing prediction accuracy across 1305 games using multiple rating models.

Model Performance Leaderboard

Models ranked by AUC on 2025-2026 games. Hover over column headers for explanations.

# Model AUC Acc Brier LogLoss n AUC 7d Acc 7d Brier 7d n 7d
1 Avg Margin (Baseline) 0.757 69.1% 0.203 0.593 1177 0.500 33.3% 0.252 3
2 Pythagorean Efficiency 0.749 67.6% 0.204 0.594 1177 - - - 0
3 Points O/D 0.748 67.2% 0.209 0.607 1177 0.250 33.3% 0.268 3
4 Pythagorean Raw 0.748 68.1% 0.216 0.622 1177 0.500 33.3% 0.250 3
5 Pythagorean Adjusted 0.746 67.6% 0.205 0.597 1177 0.500 33.3% 0.255 3
6 Pythagorean Log 0.746 67.6% 0.205 0.597 1177 0.500 33.3% 0.255 3
7 Bradley-Terry 0.744 67.8% 0.207 0.601 1177 0.500 33.3% 0.282 3
8 Margin Regression 0.739 67.3% 0.212 0.613 1177 0.250 33.3% 0.267 3
9 Pure ELO 0.738 68.1% 0.208 0.604 1177 0.500 66.7% 0.223 3
10 Home Team (Baseline) 0.549 54.9% 0.250 0.694 1177 0.250 33.3% 0.293 3
11 Bradley-Terry Recency - - - - 0 0.500 66.7% 0.225 3
12 Margin Recency - - - - 0 0.250 66.7% 0.249 3
13 Points O/D Recency - - - - 0 0.250 66.7% 0.250 3
14 Core Ensemble - - - - 0 0.250 66.7% 0.238 3
15 Recency Ensemble - - - - 0 0.250 66.7% 0.235 3
16 Adjusted Context Blend - - - - 0 0.250 33.3% 0.264 3
17 Dynamic Bradley-Terry - - - - 0 - 66.7% 0.245 3

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: Bill James formula (pts scored/allowed)
  • Efficiency: Pace-adjusted (pts per possession)
  • Adjusted: KenPom-style opponent adjustment
  • 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