Published by: FINCAD
Date: 2008
“The classic derivatives that allow investors to take a view on volatility are straddles or strangles. A long position in a straddle, for example, will generate a profit if the underlying asset price moves up or down, or if the implied volatility rises. However, these options are also sensitive to the underlying asset price, as the delta of a straddle or a strangle is zero only when the option is at-the-money.
Unlike these options, variance and volatility swaps provide pure exposure to volatility. A volatility swap is essentially a forward contract on future realized price volatility. At expiry the holder of a long position in a volatility swap receives (or owes if negative) the difference between the realized volatility and the initially chosen volatility strike, multiplied by a notional principal amount. A variance swap is analogously a forward contract on future realized price variance, which is the square of future realized volatility.
In both cases, at inception of the swap the strike is chosen such that the fair value of the swap is zero. This strike is then referred to as fair volatility and fair variance, respectively.”
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