EWMA volatility
The Exponential Weighted Moving Average estimate of daily return volatility used in margining, with the decay parameter lambda fixed at 0.995 and returns measured logarithmically.
This one is not written up yet
The definition above is the short version. A full explanation — how it works, a worked example and the exam traps — is still being written. In the meantime the chapter below covers it in context.
Written up from the same chapter
- Central counterpartyThe clearing corporation that interposes itself in every exchange trade, becoming buyer to every seller and seller to every buyer, so neither side carries the other's credit risk.
- ClearingThe daily accounting step that reconciles what every party owes and is owed on its open and closed positions, and turns a day of trades into one net obligation per member.
- Conversion factorThe multiplier that scales a futures settlement price into a fair invoice price for each bond in the deliverable basket, by valuing that bond at the notional 7% yield.
- Extreme Loss MarginA flat 3.5 per cent margin collected on cash-market positions to cover losses falling outside what the VaR margin is designed to capture.
- Invoice priceThe cash a buyer pays the seller on physical delivery: the futures settlement price multiplied by the delivered bond's conversion factor, plus its accrued interest, scaled by the contract amount.
- Liquid Net WorthThe part of a merchant banker's net worth deployed in unencumbered liquid assets, counted after a prescribed haircut on each asset type — a second capital test that net worth alone cannot satisfy.
Where this is taught
Free preparation for NISM Series IV← All terms