what is the cboe volatility index
CBOE Volatility Index. A mathematical measure of the implied volatility of options trading on the S&P 500 index. That is, the CBOE Volatility Index attempts to measure the likelihood of option prices to vary unpredictably in the context of a particular pricing model in this case, the Black-Scholes model. A higher number on the index represents greater volatility, while a lower number represents lower volatility.