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Parkinson Volatility Node

High-Low Range Volatility Estimator

IndicatorVolatilityAdvanced

Parkinson Volatility uses only the high-low range to estimate volatility, making it 5x more efficient than close-based standard deviation. It assumes prices follow a geometric Brownian motion and are lognormally distributed, providing rapid volatility assessment useful for option pricing and risk management.

Formula

PV = √[1/(4n×LN(2)) × Σ(LN(H/L))²]
Uses only high-low ratio for estimation

Parameters

ParameterDefault
period14

Use Cases

1. Option Valuation Input

Input for Black-Scholes option pricing and risk calculations.

2. Efficient Volatility Estimation

5x more efficient than standard deviation, requires only high-low data.

3. Intraday Market Stress Detection

Rapid volatility changes visible in intrabar high-low ranges.

4. Gap Risk Assessment

Captures realized intrabar volatility including gaps within timeframes.

Advantages & Limitations

Advantages

  • • Computationally efficient (only high-low)
  • • Theoretically sound (lognormal assumption)
  • • 5x better than close-only methods
  • • Fast convergence with fewer observations
!

Limitations

  • • Assumes lognormal distribution
  • • Ignores close prices entirely
  • • Can be distorted by limit moves

Tips & Best Practices

📊 Use for Option Greeks

Input this volatility directly into option pricing models for accuracy.

⚡ Compare with Other Measures

Should be ~75% of close-based standard deviation under normal conditions.

💰 Intrabar Signal

Changes quickly with each new intrabar high-low, good for near-term volatility changes.

⚠️ Watch Limit Moves

Limit up/down days produce artificially high readings that skew measurement.

Related Indicators

Garman-Klass Volatility

Advanced volatility estimator combining open, high, low, close

Rogers-Satchell Volatility

OHLC-based volatility without opening gaps assumption

Standard Deviation

Close-based volatility reference measure

ATR

Dollar-based high-low volatility measure