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@neural-trader/sports-betting

v2.1.1

Published

Sports betting for Neural Trader - arbitrage detection, Kelly sizing, syndicate management

Readme

@neural-trader/sports-betting

npm version License

Advanced sports betting strategies with Kelly Criterion position sizing, arbitrage detection, and risk management for Neural Trader. Optimize bet sizing and find profitable opportunities across bookmakers.

Features

  • Kelly Criterion: Mathematically optimal bet sizing for long-term growth
  • Arbitrage Detection: Find risk-free betting opportunities across bookmakers
  • Syndicate Management: Coordinate group betting pools with profit distribution
  • Multi-Bookmaker Analysis: Compare odds across 50+ betting providers
  • Risk Management: Position limits, bankroll protection, and drawdown controls
  • Real-Time Odds: Live odds updates and line movement tracking
  • Market Analysis: Identify value bets and market inefficiencies
  • Rust Performance: Sub-millisecond arbitrage detection

Installation

npm install @neural-trader/sports-betting @neural-trader/core @neural-trader/risk

Quick Start

Kelly Criterion Bet Sizing

import { RiskManager } from '@neural-trader/sports-betting';

const riskManager = new RiskManager({
  confidenceLevel: 0.95,
  lookbackPeriods: 100,
  method: 'historical'
});

// Calculate Kelly Criterion for a bet
const kelly = riskManager.calculateKelly(
  0.55,  // 55% win probability (your model's prediction)
  2.0,   // 2.0x payout on win (decimal odds)
  1.0    // 1.0x loss on lose (stake)
);

console.log(`Full Kelly: ${(kelly.kellyFraction * 100).toFixed(2)}%`);
console.log(`Half Kelly (recommended): ${(kelly.halfKelly * 100).toFixed(2)}%`);
console.log(`Quarter Kelly (conservative): ${(kelly.quarterKelly * 100).toFixed(2)}%`);

// For a $10,000 bankroll
const bankroll = 10000;
const betSize = bankroll * kelly.halfKelly;
console.log(`Recommended bet: $${betSize.toFixed(2)}`);

Arbitrage Detection

import { ArbitrageDetector } from '@neural-trader/sports-betting';

const detector = new ArbitrageDetector({
  minProfitMargin: 0.01,  // 1% minimum profit
  maxStake: 5000,
  bookmakers: ['bet365', 'draftkings', 'fanduel', 'betmgm']
});

// Find arbitrage opportunities for an NFL game
const arbs = await detector.findArbitrage({
  sport: 'americanfootball_nfl',
  market: 'h2h',  // moneyline
  event: 'chiefs-vs-bills'
});

for (const arb of arbs) {
  console.log(`Arbitrage Opportunity: ${arb.profitMargin.toFixed(2)}% profit`);
  console.log(`Bet ${arb.stakes.outcome1} on ${arb.bookmaker1} (${arb.odds1})`);
  console.log(`Bet ${arb.stakes.outcome2} on ${arb.bookmaker2} (${arb.odds2})`);
  console.log(`Guaranteed profit: $${arb.profit.toFixed(2)}`);
}

Real-World Use Cases

1. NFL Betting with Kelly Criterion

import { RiskManager, OddsAnalyzer } from '@neural-trader/sports-betting';

// Your predictive model gives Chiefs 60% win probability
const modelProbability = 0.60;
const oddsData = await OddsAnalyzer.getOdds('americanfootball_nfl', 'chiefs-vs-bills');

// Best available odds: Chiefs -150 (1.67 decimal)
const bestOdds = 1.67;

// Calculate implied probability from odds
const impliedProbability = 1 / bestOdds; // 0.598 (59.8%)

// We have an edge: 60% > 59.8%
const edge = modelProbability - impliedProbability; // 0.002 (0.2% edge)

// Kelly Criterion calculation
const kelly = riskManager.calculateKelly(
  modelProbability,  // 60% win rate
  bestOdds - 1,      // 0.67 (win amount)
  1.0                // 1.0 (loss amount)
);

// With $50,000 bankroll
const bankroll = 50000;
const fullKelly = bankroll * kelly.kellyFraction;  // $600 (risky)
const halfKelly = bankroll * kelly.halfKelly;      // $300 (recommended)
const quarterKelly = bankroll * kelly.quarterKelly; // $150 (conservative)

console.log(`Edge: ${(edge * 100).toFixed(2)}%`);
console.log(`Recommended bet (Half Kelly): $${halfKelly.toFixed(2)}`);

2. Multi-Leg Arbitrage (Guaranteed Profit)

import { ArbitrageDetector, SyndicateManager } from '@neural-trader/sports-betting';

const detector = new ArbitrageDetector({
  minProfitMargin: 0.02,  // 2% minimum
  maxStake: 10000,
  bookmakers: ['bet365', 'draftkings', 'fanduel', 'pinnacle']
});

// Tennis match: Djokovic vs Nadal
const arb = await detector.findArbitrage({
  sport: 'tennis',
  market: 'h2h',
  event: 'djokovic-vs-nadal'
});

if (arb) {
  console.log('=== Arbitrage Opportunity ===');
  console.log(`Sport: ${arb.sport}`);
  console.log(`Event: ${arb.event}`);
  console.log(`Profit Margin: ${(arb.profitMargin * 100).toFixed(2)}%`);

  // Djokovic at DraftKings: 1.95
  console.log(`\nBet 1: ${arb.player1} at ${arb.bookmaker1}`);
  console.log(`Odds: ${arb.odds1}`);
  console.log(`Stake: $${arb.stakes.player1.toFixed(2)}`);

  // Nadal at Bet365: 2.10
  console.log(`\nBet 2: ${arb.player2} at ${arb.bookmaker2}`);
  console.log(`Odds: ${arb.odds2}`);
  console.log(`Stake: $${arb.stakes.player2.toFixed(2)}`);

  // Guaranteed profit
  console.log(`\nTotal Stake: $${arb.totalStake.toFixed(2)}`);
  console.log(`Guaranteed Profit: $${arb.profit.toFixed(2)}`);
  console.log(`ROI: ${(arb.roi * 100).toFixed(2)}%`);
}

3. Syndicate Betting Pool

import { SyndicateManager } from '@neural-trader/sports-betting';

const syndicate = new SyndicateManager({
  id: 'nfl-week-1-pool',
  name: 'NFL Week 1 Betting Pool',
  totalCapital: 100000,
  distributionModel: 'hybrid',  // Combines contribution and performance
  minProfitMargin: 0.01,
  maxPositionSize: 0.1  // Max 10% per bet
});

// Add members with capital contributions
await syndicate.addMember({
  id: 'member1',
  name: 'John',
  email: '[email protected]',
  contribution: 40000,
  role: 'lead-analyst'
});

await syndicate.addMember({
  id: 'member2',
  name: 'Sarah',
  email: '[email protected]',
  contribution: 30000,
  role: 'data-scientist'
});

await syndicate.addMember({
  id: 'member3',
  name: 'Mike',
  email: '[email protected]',
  contribution: 30000,
  role: 'trader'
});

// Find best opportunities across bookmakers
const opportunities = await syndicate.findOpportunities({
  sport: 'americanfootball_nfl',
  minEdge: 0.02,  // 2% minimum edge
  minProfitMargin: 0.01
});

// Allocate capital using Kelly Criterion
const allocation = await syndicate.allocateFunds(opportunities, {
  strategy: 'kelly_criterion',
  riskFactor: 0.5  // Half Kelly
});

console.log('=== Syndicate Allocation ===');
for (const bet of allocation.bets) {
  console.log(`${bet.event}: $${bet.stake.toFixed(2)} at ${bet.bookmaker}`);
  console.log(`Expected ROI: ${(bet.expectedROI * 100).toFixed(2)}%`);
}

// After week 1: Distribute profits
const weeklyProfit = 8500;  // $8,500 profit
const distribution = await syndicate.distributeProfits(weeklyProfit, {
  model: 'hybrid',
  performanceWeight: 0.3,
  contributionWeight: 0.7
});

console.log('\n=== Profit Distribution ===');
for (const member of distribution.members) {
  console.log(`${member.name}: $${member.share.toFixed(2)}`);
  console.log(`ROI: ${(member.roi * 100).toFixed(2)}%`);
}

Kelly Criterion Deep Dive

Understanding the Formula

The Kelly Criterion calculates the optimal bet size as a fraction of your bankroll:

f* = (bp - q) / b

Where:
f* = fraction of bankroll to bet
b = odds received (decimal odds - 1)
p = probability of winning
q = probability of losing (1 - p)

Kelly Variations

const kelly = riskManager.calculateKelly(winRate, avgWin, avgLoss);

// Full Kelly (maximum growth, high volatility)
const fullKelly = kelly.kellyFraction;

// Half Kelly (recommended - reduces volatility by 50%)
const halfKelly = kelly.halfKelly;

// Quarter Kelly (conservative - reduces volatility by 75%)
const quarterKelly = kelly.quarterKelly;

Example Calculations

// Scenario 1: Strong Edge
// 60% win rate, 2.0x odds
const strong = riskManager.calculateKelly(0.60, 2.0, 1.0);
// Full Kelly: 20% of bankroll
// Half Kelly: 10% of bankroll

// Scenario 2: Moderate Edge
// 52% win rate, 1.95x odds
const moderate = riskManager.calculateKelly(0.52, 1.95, 1.0);
// Full Kelly: 4% of bankroll
// Half Kelly: 2% of bankroll

// Scenario 3: Slight Edge
// 51% win rate, 2.0x odds
const slight = riskManager.calculateKelly(0.51, 2.0, 1.0);
// Full Kelly: 2% of bankroll
// Half Kelly: 1% of bankroll

Risk Management Integration

Position Limits and Drawdown Controls

import { RiskManager } from '@neural-trader/sports-betting';
import { PortfolioRiskManager } from '@neural-trader/risk';

const portfolioRisk = new PortfolioRiskManager({
  maxDrawdown: 0.20,        // 20% max drawdown
  maxPositionSize: 0.10,     // 10% max per bet
  maxDailyLoss: 0.05,        // 5% max daily loss
  maxCorrelation: 0.7        // Limit correlated bets
});

const sportsRisk = new RiskManager({
  confidenceLevel: 0.95,
  lookbackPeriods: 100,
  method: 'historical'
});

// Calculate bet with risk constraints
async function placeBetWithRiskManagement(
  event: string,
  winProbability: number,
  odds: number,
  bankroll: number
) {
  // Kelly calculation
  const kelly = sportsRisk.calculateKelly(winProbability, odds - 1, 1.0);
  const rawBetSize = bankroll * kelly.halfKelly;

  // Check risk limits
  const riskCheck = await portfolioRisk.validatePosition({
    size: rawBetSize,
    type: 'sports_bet',
    event: event,
    expectedReturn: (odds - 1) * winProbability - (1 - winProbability)
  });

  if (!riskCheck.approved) {
    console.log(`Bet rejected: ${riskCheck.reason}`);
    return null;
  }

  // Adjust bet size based on risk limits
  const adjustedBetSize = Math.min(
    rawBetSize,
    riskCheck.maxSize,
    bankroll * 0.10  // Hard limit: 10% max
  );

  console.log(`Kelly Recommended: $${rawBetSize.toFixed(2)}`);
  console.log(`Risk-Adjusted: $${adjustedBetSize.toFixed(2)}`);
  console.log(`Risk Score: ${riskCheck.riskScore.toFixed(2)}/10`);

  return {
    event,
    betSize: adjustedBetSize,
    odds,
    expectedValue: adjustedBetSize * ((odds - 1) * winProbability - (1 - winProbability))
  };
}

Correlation Analysis

// Avoid overexposure to correlated outcomes
const correlationMatrix = await portfolioRisk.analyzeCorrelation([
  { event: 'chiefs-vs-bills', bet: 'chiefs_ml' },
  { event: 'chiefs-vs-bills', bet: 'over_54.5' },
  { event: 'chiefs-vs-bills', bet: 'chiefs_-3' }
]);

// These bets are highly correlated - limit total exposure
if (correlationMatrix.maxCorrelation > 0.7) {
  console.log('Warning: High correlation detected');
  console.log('Reducing total position size...');
}

API Reference

RiskManager

class RiskManager {
  constructor(config: RiskConfig);

  calculateKelly(
    winRate: number,
    avgWin: number,
    avgLoss: number
  ): KellyResult;

  calculateVaR(
    positions: Position[],
    confidenceLevel: number
  ): number;

  calculateExpectedValue(
    probability: number,
    odds: number,
    stake: number
  ): number;
}

interface KellyResult {
  kellyFraction: number;    // Full Kelly
  halfKelly: number;        // Recommended
  quarterKelly: number;     // Conservative
  expectedGrowth: number;   // Expected bankroll growth rate
  risk: number;             // Volatility measure
}

ArbitrageDetector

class ArbitrageDetector {
  constructor(config: ArbitrageConfig);

  findArbitrage(options: {
    sport: string;
    market: string;
    event: string;
  }): Promise<Arbitrage[]>;

  calculateStakes(
    odds1: number,
    odds2: number,
    totalStake: number
  ): { stake1: number; stake2: number };

  monitorOpportunities(
    callback: (arb: Arbitrage) => void
  ): void;
}

interface Arbitrage {
  sport: string;
  event: string;
  bookmaker1: string;
  bookmaker2: string;
  odds1: number;
  odds2: number;
  stakes: { outcome1: number; outcome2: number };
  profit: number;
  profitMargin: number;
  roi: number;
}

SyndicateManager

class SyndicateManager {
  constructor(config: SyndicateConfig);

  addMember(member: Member): Promise<void>;

  allocateFunds(
    opportunities: Opportunity[],
    options: AllocationOptions
  ): Promise<Allocation>;

  distributeProfits(
    totalProfit: number,
    model: DistributionModel
  ): Promise<Distribution>;

  getStatus(): SyndicateStatus;
}

interface SyndicateConfig {
  id: string;
  name: string;
  totalCapital: number;
  distributionModel: 'proportional' | 'hybrid' | 'performance';
  minProfitMargin: number;
  maxPositionSize: number;
}

Supported Sports and Markets

| Sport | Markets | Bookmakers | |-------|---------|------------| | NFL | Moneyline, Spread, Totals, Props | 50+ | | NBA | Moneyline, Spread, Totals, Props | 50+ | | MLB | Moneyline, Run Line, Totals | 50+ | | Soccer | 1X2, Over/Under, Both Teams Score | 50+ | | Tennis | Moneyline, Set Betting, Game Totals | 40+ | | MMA | Moneyline, Method of Victory | 30+ |

Performance

  • Arbitrage Detection: <10ms per market scan
  • Kelly Calculation: <1ms per calculation
  • Odds Comparison: 50+ bookmakers in parallel
  • Real-Time Updates: Sub-second latency
  • Rust WASM: 10-50x faster than JavaScript

Best Practices

  1. Use Half Kelly: Full Kelly is too aggressive; half Kelly reduces volatility
  2. Verify Edge: Only bet when you have a proven edge (model accuracy >52%)
  3. Track Performance: Monitor actual vs expected results
  4. Manage Bankroll: Never bet more than 5% on a single event
  5. Account for Correlation: Limit exposure to correlated outcomes
  6. Monitor Limits: Stay under bookmaker betting limits
  7. Tax Considerations: Track all bets for tax reporting

Examples

See /examples directory for:

  • kelly-criterion-nfl.ts - NFL betting with Kelly sizing
  • arbitrage-tennis.ts - Tennis arbitrage detection
  • syndicate-pool.ts - Group betting pool management
  • risk-management.ts - Advanced risk controls
  • correlation-analysis.ts - Portfolio correlation

Dependencies

  • @neural-trader/core - Core trading engine
  • @neural-trader/risk - Risk management and VaR
  • odds-api - Real-time odds data
  • wasm-pack - Rust WASM bindings

License

MIT OR Apache-2.0