Volatility-Based Sizing

The insight: a fixed rupee position carries wildly different risk* depending on volatilityThe size of price swings — not their direction. — so to keep risk constant, you must size **inversely to volatilityThe size of price swings — not their direction.*. A ₹1L position in a stock that swings ±2% a day is far riskier than the same ₹1L in one that moves ±0.3% — same money, very different danger. Volatility-based sizingDeciding how much to bet on each trade or holding. equalises this: you give the jumpy asset a smaller position and the calm asset a larger one, so each contributes the same risk to your portfolio. The standard tool is ATR (Average True RangeA single number for how far a stock typically moves., from the technical track): size the position so a defined multiple of ATR equals your fixed risk budgetA plan for how you’ll spend and save your income. — `sharesA unit of ownership in a company. = (capital × risk%) ÷ (ATR-based stopA pre-set exit that caps your loss if a trade goes wrong. distance)`. This makes your sizingDeciding how much to bet on each trade or holding. adaptive: in turbulent markets (high ATR) positions automatically shrink, protecting you exactly when risk is elevated (recall volatility clusters — danger persists); in calm markets they grow. It’s the sizing analogue of risk parityAllocating so each asset contributes equal risk. (equal risk contribution, not equal money) and a more sophisticated cousin of fixed-fractional. The deep principle uniting them: target a constant level of risk, and let volatility — not your gut — determine the position size that delivers it.