Stock Options Properties Flashcards
Stock Price Increase
Causes calls to increase and puts to decline
Strike Price Increase
Causes puts to increase and calls to decline
Volatility Increase
Increases the value of all options
Dividends Increase
Causes puts to increase and calls to decrease in value
Time to Maturity Increase
European options usually increase in value, but not always
Interest Rates Increase
Causes calls to increase and puts to decrease in value
Lower Bound Calculation (Call Option)
S0 − Ke-rT
Lower Bound Calculation (Put Option)
Ke-rT − S0
Intrinsic Value of an Option
The value it would have if the owner had to exercise it immediately or not at all
Put-Call Parity Result (Non-dividend-paying stock)
The European put price plus the stock price must equal the European call price plus the present value of the strike price
Volatility Decrease
Makes the option more likely to be exercised early
American Call Option Exercise
Should never be exercised early when no dividends are expected
Put-Call Parity Adjustment (Dividends Expected)
The basic put-call parity formula can be adjusted by subtracting the present value of expected dividends from the stock price
Price of European Put Option Calculation
c+Ke-rT=p+S0˗D
Effect of Volatility Increase on Put Price
Put price increases by the same amount as the call price