How Well Does Implied Volatility Predict Future Stock Index Returns and Volatility? : A Study of Option-Implied Volatility Derived from OMXS30 Index Options

Sammanfattning: The purpose of this thesis is to study if and how well implied volatility can predict realised volatility and returns on the OMXS30 index one month in the future. The findings are put in relation to how historical volatility can predict realised volatility and how changes in implied volatility can predict returns. The study covers the time period from 10th of May 2012 to 9th of February 2020 and the implied volatility used in the study is derived from an unweighted average of OMXS30 call and put option implied volatility. Six different OLS-regressions are performed to study the prediction capability of implied volatility. This study finds support of implied volatility to be a statistically significant estimate for future realised returns in a univariate regression. However, our results show that historical volatility performs slightly better predictions of realised volatility than implied volatility. These are contradictory results to the majority of the papers studied in this thesis. These papers share the common notion that implied volatility is superior to historical volatility in predicting realised volatility. Further our results show that implied volatility nor change in implied volatility are significant estimates to future realised returns and perform poorly as predictors. This result is supported by the larger part of previous research, which found implied volatility to be a weak predictor of returns.