Implements Phase 5.2 of the EV system with Harville-Malmuth Independent Chip Model
for calculating participant placement probabilities from futures odds.
## Key Features
### ICM Probability Calculator
- Implements Harville-Malmuth method for distributing probabilities
- Converts American odds to championship probabilities
- Generates P(1st) through P(8th) for all participants
- Column-normalized: each placement sums to 100% across all teams
- Works with any number of participants (not limited to 8)
### Admin UI - Futures Odds Entry
- Enter American odds (e.g., +550, -200) for championship futures
- Live preview of ICM-calculated probability distributions
- Displays all 8 placement probabilities
- Persists odds for editing on subsequent visits
- Automatic probability normalization (removes bookmaker vig)
### Database Schema Updates
- Renamed participant_expected_values.season_id → sports_season_id
- Updated foreign key to reference sports_seasons instead of seasons
- Added source_odds field to store original futures odds
- Migration 0025: Column rename and FK update
- Migration 0026: Add source_odds field
### Model Layer
- participant-expected-value: CRUD operations for probability distributions
- Supports multiple probability sources (manual, futures_odds, elo_simulation)
- Automatic EV calculation based on league scoring rules
- Probability validation and normalization
### Service Layer
- icm-calculator: Harville-Malmuth probability distribution
- probability-engine: Odds conversion and Elo utilities (for future use)
- bracket-simulator: Monte Carlo simulation (for future hybrid approach)
- ev-calculator: Expected value computation from probabilities
## Technical Details
- Uses exponential decay favoring top positions for strong teams
- Preserves championship probability ordering in final distributions
- Row sums vary (strong teams ~100%, weak teams lower)
- All probabilities between 0-1, mathematically valid
- Comprehensive test suite: 97 tests passing
## Future Enhancements
- Hybrid approach: ICM pre-playoffs, bracket simulation during playoffs
- Integration with league-specific scoring rules
- Historical probability tracking for accuracy analysis
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
- Added recharts dependency to package.json for data visualization.
- Implemented PointProgressionChart component to display team point progression over time.
- Updated scoring-system.md to reflect completion of historical views and added implementation notes.
- Created unit tests for PointProgressionChart to ensure correct rendering and data handling.
- Developed season completion detection and percentage calculation functions in season-helpers.server.ts.
- Added tests for season completion logic and point progression data formatting.
- Enhanced league loader to fetch necessary data for current season and teams.
- Added a new route for league standings: `/leagues/:leagueId/standings/:seasonId`
- Implemented the `StandingsTable` component to display team standings with ranking, points, and placement breakdown.
- Integrated tiebreaker logic for ranking teams based on total points and placements.
- Enhanced the league home page with a link to view standings.
- Updated scoring system documentation to reflect the new standings features.
- Added comprehensive tests for tiebreaker logic and `StandingsTable` component.
- Created shared types for standings to be used in both server and client code.
- Added `QualifyingPointsStandings` component to display standings based on qualifying points.
- Introduced scoring rules and projected points calculation for participants.
- Implemented tie handling for rankings and displayed appropriate UI elements based on finalization status.
- Created tests for qualifying points configuration, accumulation logic, ranking logic, and scoring workflow.
- Developed scoring calculator tests to validate fantasy points conversion from qualifying points.
- Established qualifying points management functions including initialization, retrieval, updating, and resetting of points.
- Introduced `generateStandardSeeding()` function to create proper tournament matchups (e.g., 1v16, 8v9).
- Added comprehensive tests for 4, 8, 16, and 32-team brackets to ensure correct seeding and balance.
- Updated testing instructions to reflect new features and improvements in bracket generation.
- Fixed issues with sequential seeding and ensured all matchups sum to n+1 for balance.
- Implemented batch winner selection and duplicate participant prevention for improved user experience.
- Enhanced fantasy points display on event pages for better visibility of participant results.
- Added a comprehensive plan for bracket expansion, including support for 4, 8, 16, 32, and 68 team formats.
- Introduced a template-based bracket system with predefined templates for NCAA March Madness, NFL Playoffs, NBA Playoffs, and simple brackets.
- Updated UI flow for bracket creation, allowing admins to select templates and assign participants flexibly.
- Enhanced database schema to accommodate new scoring rules and bracket templates.
- Proposed updates to scoring logic to handle non-scoring rounds and participant placements correctly.
- Documented implementation phases for gradual rollout of new features.
- Addressed critical bugs in the playoff event processing and scoring logic, ensuring proper advancement and scoring rules across multiple leagues.
