About
What This Is
The NBA Rule Impact Timeline is an interactive visualization mapping rule changes to their statistical consequences across 78 years of professional basketball. It connects causes (rule changes) to effects (statistical shifts) with curated editorial context that no existing stat site provides.
Methodology
Season averages are league-wide per-team-per-game statistics scraped from Basketball Reference. They represent the average performance of all teams in a given season.
Rule changes are hand-curated with editorial descriptions and impact assessments. Each entry is sourced from official NBA documentation, contemporary reporting, or historical analysis. The editorial layer — connecting rules to their statistical impact — is the proprietary contribution.
Before/after comparisons use 3-season windows on each side of a rule change. This smooths out year-to-year variance while keeping the comparison close enough to isolate the rule’s effect. We acknowledge that correlation is not causation — other factors (player talent, coaching trends) always contribute.
Player similarity scores use cosine similarity on z-score normalized per-season stat vectors. Z-score normalization means each player’s stats are compared relative to their era’s league averages, enabling meaningful cross-era comparison.
Data Sources
Tech Stack
Credits
Brought to you by Studio Pinball. Rule change research and editorial content is original work. Statistical data is sourced from the public domain via Basketball Reference and NBA.com. Leveraged Claude.