Narrow Results

We examine an option contract from a supplier’s perspective and apply mean-variance method to analyze the supplier’s risk. Compared with the newsvendor model without an option contract, we theoretically prove that the option contract can also benefit the supplier. We find for a given option exercise price, there exists an option price such that the contract with the option price dominates those with smaller option price in terms of mean variance of the supplier’s profit. Computational studies have also been conducted in the paper.

This paper examines mispricing, volatility and parity on the Hang Seng Index (HSI) options and futures market. Most of the previous research has focused on futures contracts; we update this research and extend it by considering also option contracts. It is also important to examine these issues post 1997 Asian crisis. We find mispricing of HSI futures and option contracts if no transaction costs were considered. However, by incorporating transaction costs, the HSI futures are bounded within the arbitrage free region and most of the mispricing of the HSI options disappears. Additional tests on the mispricing series reveals that most of the derivative HSI contracts are positively autocorrelated and that the mispricing series for both derivative contracts are not identical among the different contract months. From our results we cannot conclude that there is causal relationship between the mispricing and the spot index volatility. Finally, our empirical results show that for HSI derivative contracts future and option parity holds, supporting our mispricing test that the HSI derivative market is efficient and has not been adversely affected by the Asian economic crisis.

This paper examines the dynamics of returns and order imbalances across the KOSPI 200 cash, futures and option markets. The information effect is more dominant than the liquidity effect in these markets. In addition, returns have more predictability power for the future movements of prices than order imbalances. Information seems to be transmitted more strongly from derivative markets to their underlying asset markets than from the underlying asset markets to their derivative markets. Finally, domestic institutional investors prefer futures, domestic individual investors prefer options, and foreign investors prefer stocks relative to other investor groups when they have new information.

We assume that the call option's value is correctly priced by Black and Scholes' option pricing model in this paper. This paper derives an exact closed-form solution for implied standard deviation under the condition that the underlying asset price equals the present value of the exercise price. The exact closed-form solution provides the true implied standard deviation and has no estimate error. This paper also develops three alternative formulas to estimate the implied standard deviation if this condition is violated. Application of the Taylor expansion on a single call option value derives the first formula. The accuracy of this formula depends on the deviation between the underlying asset price and the present value of the exercise price. Use of the Taylor formula on two call option prices with different exercise prices is used to develop the second formula, which can be used even though the underlying asset price deviates significantly from the present value of the exercise price. Extension of the second formula's approach to third options value derives the third formula. A merit of the third formula is to circumvent a required parameter used in the second formula. Simulations demonstrate that the implied standard deviations calculated by the second and third formulas provide accurate estimates of the true implied standard deviations.

There are two ad hoc approaches to Black and Scholes model. The “relative smile” approach treats the implied volatility skew as a fixed function of moneyness, whereas the “absolute smile” approach treats it as a function of the strike price. Previous studies reveal that the “absolute smile” approach is superior to the “relative smile” approach as well as to other sophisticated models for pricing options. We find that the time-to-maturity factors improve the pricing and hedging performance of the ad hoc procedures and the superiority of the “absolute smile” approach still holds even after the time-to-maturity is considered.