Derivative Flashcards
Delta Hedged Portfolio - what is
Detal hedged porfolio consists of long position in stocks and short position in call options. Because the gamma of long stock position is zero and the gamma of short call is negative, the net gamma of a delta hedged portfolio is negative
Shares /delta = #of calls to short to hedge
put-call parity formula - continuous compound
and regular
Po= Co - So + X/e^(Rf*T) = continuous Po= Co - So + X/(1+Rf)^T
So + Po= Co + pvX
Po-Put price Co-Call price X-Exercise price Rf- Risk Free rate T-time in years to expiration
Forward contract price formula
FP=So * (1+Rf)^T
So=Spot price
T= Forward contract term in years
no arbitrage price of an equity forward contract
FP=(So-PVD) * (1+Rf)^T
or So*(1+Rf)^T - FVD
PVD - present value of dividends
FVD future value of the dividends
Value of the long position in a forward contract on a dividend paying stock
=(St-PVDt) - FP/(1+Rft)^(T-t)
Probabilities of an up move
Uprob= (1+Rf-D) / (U-D)
Gamma Risk
Gamma risk arises when the price of the underlying jumps abruptly. Measures the rate of change in delta as the stock price changes
Long positions in calls and puts have positive Gamma
Gamma is highest for at-the-money options
Vega
Measures the sensitivity of the option price to changes in the volatility of returns
Rho
measures the sensitivity of the option price to changes in the risk free rate
Theta
measure the sensitivity of the option price to the passage of time
Protective Put
Long stock position and long put position
Cash Secured Puts
writing a put options and deposition an amount equal to the put exercise price in a designated account.
Finding forward rate of adjacent node
If up *e^(2 * volatility)
If down /e^(2 * volatility)
FP = What
or how to calculate spot price
In the absence of an arbitrage opportunity, the value of should be 0.
Therefore, FP = S0(1 + Rf)T
Value of a Call option
Call Value = Put Value − Xe^-rt + S =
$4.78 − $100.00e(−0.07 × 1.0) + 100 = $11.54
FP (on an equity Index)
So x e ^[(Rf - Dy)T] = FP
Limitations of BSM
The following are limitations of the BSM:
The assumption of a known and constant risk free rate means the BSM is not useful for pricing options on bond prices and interest rates.
The assumption of a known and constant asset return volatility makes the BSM not useful in situations where the volatility is not constant which occurs much of the time.
The assumption of no taxes and transaction costs makes the BSM less useful.
The BSM is designed to price European options and not American options.
Bull Spread vs Bear
Can use calls or puts:
The exercise price of the long option is lower than the exercise price of the short option.
Bear is the reverse. The Exercise price of the long option is higher than the price of the short.