EMBA 693R · Advanced Machine Learning

The March Madness Retrospective

Eight prediction models walked into a bracket. Only one of them knew how it ended. Here's how each model fared against the 2026 tournament, round by round — and what the games actually rewarded.

How each model fared

Pre-tournament bracket vs what actually happened, across 67 games.

Accuracy, round by round

The shape of each model's failure: where Vegas bled out, where Greg_v1 held up.

Champion picks

Who each model crowned before the tournament tipped off.

The upsets that defined the tournament

Games won by the higher-numbered seed. The model tags show who had the guts to call it.

Every model's bracket, side by side with what happened

Switch between models. Green checks = model nailed it. Red X = model whiffed.

What actually mattered in 2026

The Hindsight model is a gradient-boosted regressor trained directly on this tournament's 67 games. It fits the data almost perfectly by construction — but its feature importances tell us which variables carried the signal this year.

Reading this honestly

A model trained on its own test set is a caricature of predictive power. The point isn't the accuracy — it's the shape of the importance chart. Features that rank high here are ones whose pre-tournament values cleanly separated this year's winners from losers. Features that rank low were either noisy, correlated with higher-ranked ones, or genuinely irrelevant to how 2026 played out.

Feature importances — fitted on 2026 alone

Ranked by gain in the gradient-boosted margin model. Higher = more predictive of the games that were actually played.

Method & documentation

Everything you'd want to know to reproduce this work or extend it.

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