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