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decaying time value of options

Dissecting Decaying Time Value of Options with respect to Market States of the Underlying Assets

This thesis proposes a different methodology to measure the speed with which an option’s time value approaches zero as the time to maturity T vanishes other than the Greek letter theta: the slope of a fourth-order polynomial fitted line implied from a term decay plot which plots the log of option price against the log of time to maturity. I hypothesize that when the market state of the underlying asset of options is bullish, the time value of put options decreases faster whereas when the market state of the underlying asset of options is bearish, the time value of call options decreases faster. Three methodologies are used to proxy for the market states of the underlying asset of options including past returns of the underlying asset price, Bry Boschan dating algorithm to classify the market into bull or bear, and Bollinger Bands to classify the market into bull, bear, or mean-reversion. We find international evidence that the hypothesis holds for the index options across countries including Taiwan, Hong Kong, South Korea, Japan, and Malaysia. The empirical results have huge implication for options trading and hedging in that they can construct better trading or hedging strategies by taking advantage of these findings.