Chapter 14 Option Market – Part II Call Options Payoffs and Profits at Expiration Payoff to call holder (buyer) max {ST – X, 0} Payoff to call writer (seller) - max {ST – X, 0} Profit to call holder max {ST – X, 0} - Premium Profit to Call Writer Premium - max {ST – X, 0} 5/9/2006 FIN3710 - Investment - Professor Rui Yao 2 1 Payoff Profiles for Calls Profit OTM ITM Call Holder 0 Stock Price at time T X Call Writer 5/9/2006 FIN3710 - Investment - Professor Rui Yao 3 Profit/Loss Profiles for Calls Profit Call Holder OTM ITM C 0 Stock Price at time T X -C Call Writer Stock Price 5/9/2006 FIN3710 - Investment - Professor Rui Yao 4 2 Put Options Payoffs and Profits at Expiration Payoff to put holder (buyer) max {X - ST, 0} Payoff to put writer (seller) - max {X - ST, 0} Profit to put holder max {X - ST, 0} - Premium Profit to put Writer Premium - max {X - ST, 0} 5/9/2006 FIN3710 - Investment - Professor Rui Yao 5 Payoff Profiles for Puts Profits ITM OTM Put Holder 0 X Stock Price at time T Put Writer 5/9/2006 FIN3710 - Investment - Professor Rui Yao 6 3 Profit/Loss Profiles for Puts Profits ITM OTM Put Writer P 0 Stock Price at time T X -P Put Holder Stock Price 5/9/2006 FIN3710 - Investment - Professor Rui Yao 7 Put-Call Parity Relationship ST < X ST > X 0 ST - X Payoff for Holding a Call Payoff for Writing A Put - (X - ST) Total Payoff ST - X 5/9/2006 FIN3710 - Investment - Professor Rui Yao 0 ST - X 8 4 Payoff of a Long Call and A Short Put Payoff Long Call Combined Payoff X Stock Price Short Put -X 5/9/2006 FIN3710 - Investment - Professor Rui Yao 9 Payoff of a Leverage Equity Payoff Long Stock Combined Payoff X -X 5/9/2006 Stock Price Short Bond FIN3710 - Investment - Professor Rui Yao 10 5 Put-Call Parity We can replicate the payoff from a long call and a short put by: ¾ ¾ Long 1 share of stock today and hold it to T; Borrow a margin loan in the amount of X / (1 + rf)T Since the payoff on a long call and a short put are equivalent to leveraged equity, the prices must be equal today: C - P = S0 - X / (1 + rf)T If the prices are not equal, arbitrage will be possible 5/9/2006 FIN3710 - Investment - Professor Rui Yao 11 An Example – Put Call Parity Arbitrage Q: A: Stock Price = 110 Call Price = 17 Risk Free = 5% Put Price = 5 Maturity = 1 yr Strike Price = 105 Is there any arbitrage opportunity? C - P > S0 - X / (1 + rf)T 17- 5 > 110 - (105/1.05) 12 > 10 Arbitrage opportunity: ¾ ¾ The leveraged equity is less expensive Buy (long) the low cost portfolio and sell (short) the high cost alternative 5/9/2006 FIN3710 - Investment - Professor Rui Yao 12 6 An Example – Put-Call Parity Arbitrage Position Immediate Cashflow Buy Stock -110 Cashflow in Six Months ST <105 ST > 105 ST ST Borrow X/(1+r)T = 100 +100 -105 -105 Sell Call +17 0 Buy Put -5 Total 2 -(ST - 105) 105 - ST 0 0 5/9/2006 0 FIN3710 - Investment - Professor Rui Yao 13 Option Strategy I – Protective Put Long stock + Long (ATM) put ¾ Pay put premium for downside protection Payoff from A Protective put Payoff from Long a stock X P/L from Holding stock ST P/L from A Protective put X - S0 X -P X Payoff from Long a put X 5/9/2006 ST ST FIN3710 - Investment - Professor Rui Yao 14 7 Option Strategy II – Covered Call Long stock + short (sell / write) call ¾ Sacrifice upside potential for call premium Covered Call Write a call Payoff at T X ST payoff X profit Payoff at T X Long a stock C-S0 ST X 5/9/2006 ST FIN3710 - Investment - Professor Rui Yao 15 Option Strategy III - Straddle Long call and put with same strike price ¾ Benefit from big jumps in stock prices Payoff at T Long Dec 160 call X=160 ST X Straddle X-P-C Long Dec 160 Put X X 5/9/2006 X ST ST FIN3710 - Investment - Professor Rui Yao 16 8 Wrap-up Payout and P/L for holders and sellers of put or call options Put-call parity Three option strategies ¾ ¾ ¾ Protective put Covered call Straddle 5/9/2006 FIN3710 - Investment - Professor Rui Yao 17 9