Problem Set 6

Options, Futures and Derivative Securities

Solutions

Instructions: This problem set is due on 4/14 at 11:59 pm CST and is an individual assignment. All problems must be handwritten. Scan your work and submit a PDF file. For all probability computations, use the table at the end of this assignment.

Note: All interest rates and dividend yields are expressed per year with continuous compounding.

Problems

Problem 1 What is the price of a European put option on a non-dividend-paying stock when the stock price is $88, the strike price is $90, the risk-free interest rate is 5% per annum, the volatility is 45% per annum, and the time to maturity is eight months?

Problem 2 Consider an option on a non-dividend-paying stock when the stock price is $50, the exercise price is $49, the risk-free interest rate is 4.5%, the volatility is 38% per annum, and the time to maturity is three months.

  1. What is the price of the option if it is a European call?
  2. What is the price of the option if it is an American call?
  3. What is the price of the option if it is a European put?
  4. Verify that put-call parity holds.

Problem 3 Consider a European call option expiring in 6 months and with strike price equal to $48 on a non-dividend paying stock that currently trades for $50. Interestingly, the volatility of the stock is zero. If the risk-free rate is 8% per year with continuous compounding, what is the price of the option?

Problem 4 Consider a European call option expiring in 6 months and with strike price equal to $52 on a non-dividend paying stock that currently trades for $50. Interestingly, the volatility of the stock is zero. If the risk-free rate is 5% per year with continuous compounding, what is the price of the option?

Problem 5 Consider a European put option expiring in 9 months and strike price $152 written on a non-dividend paying stock. The risk-free rate is 6% per year with continuous compounding and the stock price is $150. What is the minimum price for the put that would allow you to compute its implied volatility?

Problem 6 Suppose that the sales team of a trading desk just sold a European call option contract, that is 100 European call options, to an important client. The contract is written on a non-dividend paying stock that trades for $150, expires in two years and has a strike price of $155. The risk-free rate is 5% per year with continuous compounding. A trader of the desk estimate that the volatility of the stock returns is 55% and expected to remain constant for the life of the contract.

  1. How many shares of the stock does the trader need to buy/sell initially in order to hedge the exposure created by the sale of the contract?
  2. How many risk-free bonds with face value $155 and expiring in two years does the trader need to buy/sell in order to make sure that the strategy is self-financing?
  3. How many risk-free bonds with face value $100 and expiring in two years does the trader need to buy/sell in order to make sure that the strategy is self-financing?
  4. Why choosing a different face value for the bonds does not change the price of the call option.

Problem 7 A call option on a non-dividend-paying stock has a market price of $12.39. The stock price is $100, the exercise price is $100, the time to maturity is six months, and the risk-free interest rate is 5% per annum. What is the implied volatility of the call? Explain the method you used to find the implied volatility.

Problem 8 Calculate the value of a three-month at-the-money European call option on a stock index when the index is at 5,000, the risk-free interest rate is 5% per annum, the volatility of the index is 30% per annum, and the dividend yield on the index is 2% per annum.

Problem 9 The S&P 100 index currently stands at 2,392 and has a volatility of 50% per annum. The risk-free rate of interest is 4% per annum and the index provides a dividend yield of 1% per annum. Calculate the value of a three-month European put with strike price 2,300.

The Standard Normal Distribution

The following table reports values for \phi(z) = P(Z ≤ z), where Z \sim \mathcal{N}(0, 1).

z P(Z ≤ z) z P(Z ≤ z) z P(Z ≤ z) z P(Z ≤ z)
-2.37 0.0089 -1.17 0.1210 0.03 0.5120 1.23 0.8907
-2.32 0.0102 -1.12 0.1314 0.08 0.5319 1.28 0.8997
-2.27 0.0116 -1.07 0.1423 0.13 0.5517 1.33 0.9082
-2.22 0.0132 -1.02 0.1539 0.18 0.5714 1.38 0.9162
-2.17 0.0150 -0.97 0.1660 0.23 0.5910 1.43 0.9236
-2.12 0.0170 -0.92 0.1788 0.28 0.6103 1.48 0.9306
-2.07 0.0192 -0.87 0.1922 0.33 0.6293 1.53 0.9370
-2.02 0.0217 -0.82 0.2061 0.38 0.6480 1.58 0.9429
-1.97 0.0244 -0.77 0.2206 0.43 0.6664 1.63 0.9484
-1.92 0.0274 -0.72 0.2358 0.48 0.6844 1.68 0.9535
-1.87 0.0307 -0.67 0.2514 0.53 0.7019 1.73 0.9582
-1.82 0.0344 -0.62 0.2676 0.58 0.7190 1.78 0.9625
-1.77 0.0384 -0.57 0.2843 0.63 0.7357 1.83 0.9664
-1.72 0.0427 -0.52 0.3015 0.68 0.7517 1.88 0.9699
-1.67 0.0475 -0.47 0.3192 0.73 0.7673 1.93 0.9732
-1.62 0.0526 -0.42 0.3372 0.78 0.7823 1.98 0.9761
-1.57 0.0582 -0.37 0.3557 0.83 0.7967 2.03 0.9788
-1.52 0.0643 -0.32 0.3745 0.88 0.8106 2.08 0.9812
-1.47 0.0708 -0.27 0.3936 0.93 0.8238 2.13 0.9834
-1.42 0.0778 -0.22 0.4129 0.98 0.8365 2.18 0.9854
-1.37 0.0853 -0.17 0.4325 1.03 0.8485 2.23 0.9871
-1.32 0.0934 -0.12 0.4522 1.08 0.8599 2.28 0.9887
-1.27 0.1020 -0.07 0.4721 1.13 0.8708 2.33 0.9901
-1.22 0.1112 -0.02 0.4920 1.18 0.8810 2.37 0.9911