Question 793 option, hedging, delta hedging, gamma hedging, gamma, Black-Scholes-Merton option pricing
A bank buys 1000 European put options on a $10 non-dividend paying stock at a strike of $12. The bank wishes to hedge this exposure. The bank can trade the underlying stocks and European call options with a strike price of 7 on the same stock with the same maturity. Details of the call and put options are given in the table below. Each call and put option is on a single stock.
| European Options on a Non-dividend Paying Stock | |||
| Description | Symbol | Put Values | Call Values |
| Spot price ($) | ##S_0## | 10 | 10 |
| Strike price ($) | ##K_T## | 12 | 7 |
| Risk free cont. comp. rate (pa) | ##r## | 0.05 | 0.05 |
| Standard deviation of the stock's cont. comp. returns (pa) | ##\sigma## | 0.4 | 0.4 |
| Option maturity (years) | ##T## | 1 | 1 |
| Option price ($) | ##p_0## or ##c_0## | 2.495350486 | 3.601466138 |
| ##N[d_1]## | ##\partial c/\partial S## | 0.888138405 | |
| ##N[d_2]## | ##N[d_2]## | 0.792946442 | |
| ##-N[-d_1]## | ##\partial p/\partial S## | -0.552034778 | |
| ##N[-d_2]## | ##N[-d_2]## | 0.207053558 | |
| Gamma | ##\Gamma = \partial^2 c/\partial S^2## or ##\partial^2 p/\partial S^2## | 0.098885989 | 0.047577422 |
| Theta | ##\Theta = \partial c/\partial T## or ##\partial p/\partial T## | 0.348152078 | 0.672379961 |
Which of the following statements is NOT correct?