# Phase 4: Monte Carlo & Risk Analysis Implementation
## Overview
Implement 4 advanced risk analysis tools that provide sophisticated risk assessment and scenario testing capabilities.
## Status: Planning
**Start Date**: 2025-11-27
**Estimated Duration**: 2-3 weeks
## Phase 4 Tools (4 of 16)
### 1. `monte_carlo()` - Advanced Monte Carlo Simulation
**Purpose**: Generate random walks for comprehensive risk analysis
**Input Parameters**:
- `backtest_result`: Result from backtest() or backtest_batch()
- `simulations`: Number of Monte Carlo runs (default: 10000)
- `confidence_levels`: List of confidence levels (default: [0.95, 0.99])
- `resample_method`: "bootstrap", "block_bootstrap", "stationary_bootstrap" (default: "bootstrap")
- `block_size`: Block size for block bootstrap (default: 20)
- `include_drawdowns`: Include drawdown analysis (default: true)
- `include_returns`: Include return distribution analysis (default: true)
**Output**:
- Final value distribution with percentiles
- Confidence intervals for key metrics
- Drawdown distribution analysis
- Return distribution statistics
- Probability of success metrics
- Visual data for plotting
**Implementation Approach**:
```python
def monte_carlo(backtest_result, simulations=10000, confidence_levels=[0.95, 0.99], ...):
# Extract equity curve and returns
equity_curve = backtest_result["equity_curve"]
returns = [point["return"] for point in equity_curve]
# Generate Monte Carlo paths
final_values = []
drawdowns = []
for i in range(simulations):
if resample_method == "bootstrap":
# Bootstrap resampling
sampled_returns = np.random.choice(returns, size=len(returns), replace=True)
elif resample_method == "block_bootstrap":
# Block bootstrap for preserving autocorrelation
sampled_returns = block_bootstrap(returns, block_size)
elif resample_method == "stationary_bootstrap":
# Stationary bootstrap for time series
sampled_returns = stationary_bootstrap(returns)
# Generate path
path_value = 10000 # Starting value
path_drawdown = 0
peak_value = 10000
for ret in sampled_returns:
path_value *= (1 + ret)
peak_value = max(peak_value, path_value)
current_dd = (peak_value - path_value) / peak_value
path_drawdown = max(path_drawdown, current_dd)
final_values.append(path_value)
drawdowns.append(path_drawdown)
# Calculate statistics and confidence intervals
return {
"final_value_stats": calculate_distribution_stats(final_values),
"drawdown_stats": calculate_distribution_stats(drawdowns),
"confidence_intervals": calculate_confidence_intervals(final_values, confidence_levels),
"probability_of_profit": len([v for v in final_values if v > 10000]) / simulations,
"simulations": simulations,
"method": resample_method
}
```
### 2. `var_calculation()` - Value at Risk Analysis
**Purpose**: Calculate various VaR measures for risk quantification
**Input Parameters**:
- `backtest_result`: Result from backtest() or backtest_batch()
- `confidence_levels`: List of confidence levels (default: [0.90, 0.95, 0.99])
- `time_horizons`: List of time horizons in days (default: [1, 5, 10, 30])
- `method`: "historical", "parametric", "monte_carlo" (default: "historical")
- `monte_carlo_sims`: Number of simulations for Monte Carlo VaR (default: 10000)
**Output**:
- VaR values for all confidence levels and time horizons
- Expected Shortfall (ES) values
- Conditional VaR (CVaR) calculations
- Historical VaR backtesting
- VaR exceedance analysis
- Risk metrics comparison
**Implementation Approach**:
```python
def var_calculation(backtest_result, confidence_levels=[0.90, 0.95, 0.99],
time_horizons=[1, 5, 10, 30], method="historical"):
# Extract returns
equity_curve = backtest_result["equity_curve"]
returns = [point["return"] for point in equity_curve]
var_results = {}
for horizon in time_horizons:
# Aggregate returns for horizon
horizon_returns = aggregate_returns(returns, horizon)
for confidence in confidence_levels:
if method == "historical":
var = np.percentile(horizon_returns, (1 - confidence) * 100)
es = np.mean(horizon_returns[horizon_returns <= var])
elif method == "parametric":
# Assume normal distribution
mean = np.mean(horizon_returns)
std = np.std(horizon_returns)
var = mean + norm.ppf(1 - confidence) * std
es = mean - norm.pdf(norm.ppf(1 - confidence)) * std / (1 - confidence)
elif method == "monte_carlo":
# Monte Carlo simulation
var, es = monte_carlo_var(horizon_returns, confidence, monte_carlo_sims)
var_results[f"{horizon}d_{confidence*100}%"] = {
"var": var,
"expected_shortfall": es,
"method": method
}
return {
"var_results": var_results,
"confidence_levels": confidence_levels,
"time_horizons": time_horizons,
"method": method,
"backtest_stats": calculate_backtest_stats(returns)
}
```
### 3. `stress_test()` - Black Swan Scenario Testing
**Purpose**: Test strategy performance under extreme market conditions
**Input Parameters**:
- `backtest_result`: Result from backtest() or backtest_batch()
- `scenarios`: Predefined scenarios or custom (default: ["market_crash", "volatility_spike", "correlation_breakdown"])
- `custom_scenarios`: Custom scenario definitions
- `shock_magnitude`: Shock magnitude for scenarios (default: -0.20 for -20%)
- `volatility_multiplier`: Volatility increase factor (default: 3.0)
- `correlation_shift`: Correlation regime shift (default: 0.8)
- `recovery_periods`: Recovery period analysis in days (default: [5, 10, 20, 30])
**Output**:
- Performance under each stress scenario
- Recovery time analysis
- Maximum drawdown under stress
- Scenario comparison matrix
- Stress test summary statistics
- Risk factor sensitivity analysis
**Implementation Approach**:
```python
def stress_test(backtest_result, scenarios=["market_crash", "volatility_spike", "correlation_breakdown"],
shock_magnitude=-0.20, volatility_multiplier=3.0):
# Extract base data
equity_curve = backtest_result["equity_curve"]
returns = [point["return"] for point in equity_curve]
stress_results = {}
for scenario in scenarios:
if scenario == "market_crash":
# Apply sudden market crash
stressed_returns = apply_market_crash(returns, shock_magnitude)
elif scenario == "volatility_spike":
# Increase volatility
stressed_returns = apply_volatility_spike(returns, volatility_multiplier)
elif scenario == "correlation_breakdown":
# Break correlation assumptions
stressed_returns = apply_correlation_breakdown(returns, correlation_shift)
# Calculate stressed performance
stressed_equity = generate_equity_curve(stressed_returns)
max_dd = calculate_max_drawdown(stressed_equity)
recovery_times = calculate_recovery_times(stressed_equity, recovery_periods)
stress_results[scenario] = {
"scenario": scenario,
"shock_applied": shock_magnitude if scenario == "market_crash" else volatility_multiplier,
"max_drawdown": max_dd,
"final_return": stressed_returns[-1] if stressed_returns else 0,
"recovery_analysis": recovery_times,
"stressed_returns": stressed_returns[:100] # First 100 for analysis
}
return {
"stress_results": stress_results,
"base_performance": backtest_result,
"scenario_comparison": compare_scenarios(stress_results),
"risk_assessment": assess_stress_resilience(stress_results)
}
```
### 4. `risk_report()` - Comprehensive Risk Analysis
**Purpose**: Generate professional risk assessment report
**Input Parameters**:
- `backtest_result`: Result from backtest() or backtest_batch()
- `include_monte_carlo`: Include Monte Carlo analysis (default: true)
- `include_var_analysis`: Include VaR calculations (default: true)
- `include_stress_test`: Include stress testing (default: true)
- `monte_carlo_sims`: Monte Carlo simulations (default: 5000)
- `report_format`: "summary", "detailed", "executive" (default: "summary")
**Output**:
- Overall risk rating and score
- Risk factor breakdown
- Key risk metrics dashboard
- Risk-adjusted performance measures
- Recommendations for risk management
- Professional report formatting
**Implementation Approach**:
```python
def risk_report(backtest_result, include_monte_carlo=True, include_var_analysis=True,
include_stress_test=True, report_format="summary"):
report = {
"strategy": backtest_result.get("strategy"),
"symbol": backtest_result.get("symbol"),
"timeframe": backtest_result.get("timeframe"),
"period": f"{backtest_result.get('start_date')} to {backtest_result.get('end_date')}",
"generated_at": datetime.now().isoformat()
}
# Base risk metrics
report["base_metrics"] = calculate_base_risk_metrics(backtest_result)
# Monte Carlo analysis
if include_monte_carlo:
report["monte_carlo"] = monte_carlo(backtest_result, simulations=monte_carlo_sims)
# VaR analysis
if include_var_analysis:
report["var_analysis"] = var_calculation(backtest_result)
# Stress testing
if include_stress_test:
report["stress_test"] = stress_test(backtest_result)
# Overall risk assessment
report["risk_assessment"] = comprehensive_risk_assessment(report)
# Recommendations
report["recommendations"] = generate_risk_recommendations(report)
# Format based on report type
if report_format == "executive":
return format_executive_report(report)
elif report_format == "detailed":
return format_detailed_report(report)
else:
return format_summary_report(report)
```
## Dependency Status
### Required Libraries
- ✅ `numpy`, `pandas` - Data analysis (already available)
- ✅ `scipy` - Statistical analysis (already available)
- ✅ `scipy.stats` - Statistical distributions (already available)
- ✅ `matplotlib` - Optional for visualization (may need to add)
- ✅ `seaborn` - Optional for advanced plots (may need to add)
### Integration Points
1. All tools depend on existing backtest results from Phase 1-3
2. Tools should use the `Phase3Optimizer` class for consistency
3. Error handling should be consistent with previous phases
4. Mock implementations should work alongside real calculations
## Implementation Timeline
### Week 1: Foundation
- [ ] Set up statistical analysis framework
- [ ] Implement `monte_carlo()` with bootstrap methods
- [ ] Add confidence interval calculations
- [ ] Create integration tests
### Week 2: Risk Metrics
- [ ] Implement `var_calculation()` with multiple methods
- [ ] Add Expected Shortfall calculations
- [ ] Implement `stress_test()` with scenario framework
- [ ] Create scenario comparison utilities
### Week 3: Reporting & Polish
- [ ] Implement `risk_report()` with comprehensive analysis
- [ ] Add professional report formatting
- [ ] Create visualization data generators
- [ ] Comprehensive testing and documentation
## Design Patterns
### Pattern 1: Progressive Analysis
```python
# Allows different levels of risk analysis
basic_risk = risk_report(result, include_monte_carlo=False)
standard_risk = risk_report(result, include_var_analysis=True)
comprehensive_risk = risk_report(result, include_all=True)
```
### Pattern 2: Scenario Framework
```python
# Extensible scenario testing framework
scenarios = [
{"name": "market_crash", "params": {"shock": -0.20}},
{"name": "volatility_spike", "params": {"multiplier": 3.0}},
{"name": "custom", "params": custom_params}
]
stress_results = stress_test(result, scenarios=scenarios)
```
### Pattern 3: Confidence Intervals
```python
# Consistent confidence interval calculations
ci_95 = calculate_confidence_interval(data, 0.95)
ci_99 = calculate_confidence_interval(data, 0.99)
multiple_ci = calculate_confidence_intervals(data, [0.90, 0.95, 0.99])
```
## Technical Challenges & Solutions
### Challenge 1: Computational Complexity
**Issue**: Monte Carlo with 10,000+ simulations can be slow
**Solution**:
- Implement efficient vectorized operations
- Use numpy random number generation
- Add progress callbacks for long operations
- Implement early stopping for convergence
### Challenge 2: Statistical Assumptions
**Issue**: Different VaR methods make different assumptions
**Solution**:
- Implement multiple methods (historical, parametric, Monte Carlo)
- Document assumptions clearly
- Provide method comparison
- Allow user to choose appropriate method
### Challenge 3: Scenario Realism
**Issue**: Stress scenarios need to be realistic
**Solution**:
- Base scenarios on historical events
- Use realistic shock magnitudes
- Provide scenario customization
- Include recovery period analysis
## Testing Strategy
### Unit Tests
- Test statistical calculations with known datasets
- Test confidence interval calculations
- Test scenario application
- Test report generation
### Integration Tests
- Test with real backtest results
- Test tool chaining (backtest → risk_report)
- Test performance with large datasets
- Test error scenarios
### Performance Tests
- Benchmark Monte Carlo simulation speed
- Measure memory usage with large simulations
- Test concurrent execution
- Profile bottlenecks
## Phase 4 Success Criteria
✅ All 4 tools fully implemented
✅ Tests > 90% coverage
✅ Documentation complete
✅ Works with mock and real data
✅ Monte Carlo < 30 seconds (10,000 simulations)
✅ VaR calculations < 5 seconds
✅ Stress testing < 10 seconds
✅ Professional report formatting
## Next Steps (If Phase 4 Complete)
### Phase 5: Pairs Trading & Advanced (4 tools)
- `correlation_matrix()` - Cross-asset analysis
- `pairs_backtest()` - Pairs trading strategies
- `factor_analysis()` - Factor decomposition
- `regime_detector()` - Market regime analysis
### Phase 6: Autonomous Workflows (4 tools)
- `auto_optimize()` - Fully autonomous optimization
- `strategy_evolution()` - Strategy improvement over time
- `portfolio_optimizer()` - Multi-strategy portfolio optimization
- `risk_budget_allocator()` - Risk budget allocation
## Resources & References
- **Monte Carlo Methods**: https://en.wikipedia.org/wiki/Monte_Carlo_method
- **Value at Risk**: https://en.wikipedia.org/wiki/Value_at_risk
- **Stress Testing**: https://www.investopedia.com/terms/s/stresstesting.asp
- **Bootstrap Methods**: https://en.wikipedia.org/wiki/Bootstrapping_(statistics)
- **Jesse Docs**: https://docs.jesse.trade/