SUMMARY:
- Lecture 3 title slide (slide 1)
- reminder of the three equations in three unknowns;
pricers know the $2.97 price; want to "get hedge",
i.e., to find the hedge parameters x and y; enough to find x (slide 2)
- finding x by manipulating the equations (slide 3)
- finding x by manipulating the graphic (slides 4-5)
- the difference of a generic portfolio (slide 6)
- the difference of a portfolio determines how many
Euros it has (slide 7)
- same difference as a 50 Euro portfolio implies 50 Euros (slide 8)
- general form: if the difference of a portfolio agrees with
that of N units of the risky asset, then the portfolio contains
exactly N units of the risky asset; all difference comes from
the risky asset, none from the risk-free asset (slide 9)
- the hedge parameter x is a difference quotient;
in the limit, it's a rate of change (slide 10)
- going from x to y; reminder of the graphic (slides 11-12)
- the graphic with the values of x, y and ? (slide 13)
- Cathy tries to undercut Alice; Alice's response (slide 14)
- computation of the cash flow from Alice's response (slide 15-17)
- the concept of arbitrage; Cathy's undercutting Alice
introduces arbitrage (slide 18)
- the value of the hedging portfolio is the value of the option,
i.e., the value of the derivative, an illustration with Cathy and
Fred (slides 19-21)
- the "Delta" of the option, for Cathy and Fred;
no hedging at the end of the option;
beginning of rouding error analysis (slides 22-24)
- end of rounding error analysis (slide 25)
- the risk-free (bank loan) side of the hedge, an illustration
with Cathy and Fred (slide 26)
- remainder of lecture:
more practice pricing and hedging;
obligation derivatives;
put-call parity;
forwards and futures;
an option whose hedging strategy involves
millions of adjustments
(slide 27)
- second act of Lecture 3 title slide (slide 28)
- the template for Gail and Harry, with no hedge parameters filled in;
calculation of the Delta of the option at one of the nodes;
start of analysis of rounding error
(slide 29)
- end of analysis of rounding error (slide 30)
- the other hedging parameter at the same node;
solving the "equation of the node" (slides 31-32)
- hedging parameters are calculated node-by-node,
and the ordering of the nodes is completely arbitrary;
by constrast, underlying values are calculated forward in time,
while derivative values are calculated backward in time (slide 33)
- the template filled in with values to high accuracy;
the payoff function connects the underlying to the derivative (slide 34)
- Irwin's three month plight seeking to *sell*; Gail sells the option;
put options vs. call options; strike price or exercise price;
the term of the option (slide 35)
- the payoff function for Irwin's put option; comparison with
the payoff function for Harry's call option (slide 36)
- the risk-neutral probabilities (slide 37)
- Gail template for Irwin's put option (slide 38)
- Jack's plight; Gail sells this option, too; "obligation derivative"
(a.k.a. "off-market forward"); promised underlying;
receivable dollars or strike price; payoff function (slide 39)
- the template for the obligation derivative;
the Delta is constant (slide 40)
- the other hedge parameter depends only on the month,
grows by the risk-free factor in all scenarios (slide 41)
- simple description of the hedging strategy;
complete markets; completeness implies that, if you find
a hedging strategy that works, you know it's the only one that
works (slide 42)
- for an obligation derivative, you can hedge the promised underlying
and the receivable dollars separately; this hedge works, so it's
the only one that works; obligation derivative price is
inital price of underlying minus present value of receivables (slide 43)
- remainder of lecture:
put-call parity;
forwards and futures;
an option whose hedging strategy involves
millions of adjustments
(slide 44)
- third act of Lecture 3 title slide (slide 45)
- the reproducing equation; the payoff functions f,g,h for Harry, Irwin
and Jack (put, call, obligation derivative); f-g=h by the
reproducing equation (slide 46)
- the initial nodes for Jack, Harry and Irwin;
call price minus put price is obligation derivative price;
similar result for hedging parameters (slide 47)
- obligation derivatives are easy to price by completeness,
call price minus put price is equal to
inital price of underlying minus present value of receivables;
assumptions(slide 48)
- put-call parity (slide 49)
- the three equalities (slide 50)
- failure of put-call parity yields model-independent arbitrage (slide 51)
- pricing of forwards; forward is a special kind of obligation derivative
and so can be priced by market completeness; a mispriced forward
yields immediate model-independent arbitrage (slide 52)
- futures; margin requirements and margin calls (slide 53)
- Kyle's plight; a call option with millions of hedging adjustments;
saved by the Central Limit Theorem