Black-Scholes options pricing

Options are the world's most widely used derivative to help manage asset price risk. In this exercise you'll price a European call option on IBM's stock using the Black-Scholes option pricing formula. IBM_returns data has been loaded in your workspace.

First you'll compute the volatility sigma of IBM_returns, as the annualized standard deviation.

Next you'll use the function black_scholes(), created for this and the following exercises, to price options for two different volatility levels: sigma and two times sigma.

The strike price K, i.e. the price an investor has the right (but not the obligation) to buy IBM, is 80. The risk-free interest rate r is 2% and the market spot price S is 90.

You can find the source code of the black_scholes() function here.

Compute the volatility of IBM_returns as the annualized standard deviation sigma (you annualized volatility in Chapter 1).
Calculate the Black-Scholes European call option price value_s using the black_scholes() function provided, when volatility is sigma.
Next find the Black-Scholes option price value_2s when volatility is instead 2 * sigma.
Display value_s and value_2s to examine how the option price changes with an increase in volatility.

Exercise

Black-Scholes options pricing

Instructions