Adds a new `nba_bracket` simulator that projects both regular season
seedings and the full NBA playoff bracket, unlike other simulators that
operate on a pre-set bracket stored in the DB.
Algorithm:
- Per iteration: each team draws a conference seed (1–10) weighted by
BBRef seed probabilities, then seeds 7–10 play the Play-In tournament
(single elimination), then the resulting 8-team bracket is simulated
as best-of-7 series using Elo playoff ratings
- Elo source: playoff rating (last 110 games, no regression to mean,
postseason games weighted 3×) — appropriate for playoff matchup quality
- Seed probs source: Basketball-Reference (March 16, 2026), scaled from
conditional to unconditional by multiplying by each team's Playoffs%
Placement tiers map to SimulationProbabilities:
probFirst/Second → NBA champion / Finals loser
probThird/Fourth → Conference Finals losers (2 per sim)
probFifth–Eighth → Conference Semis losers (4 per sim)
Files:
- app/services/simulations/nba-simulator.ts (new)
- drizzle/0046_add_nba_bracket_simulator_type.sql (new)
- database/schema.ts: adds `nba_bracket` to simulatorTypeEnum
- app/services/simulations/registry.ts: registers NBASimulator
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
