f(σM′,r,T−t,P,ΔP%)=e(r−0.5σM2)(T−t)+σMT−tΦ(P)−1−ΔP%f′(σM′,r,T−t,P)=((T−t)σM−T−tΦ(P))e(r−0.5σM2)(T−t)+σMT−tΦ(P)
σMn+1=σMn−f′(σMn,r,T−t,P)f(σMn,r,T−t,P,ΔP%)limn→∞σMn=σM′
σMσM′σ′=σσMσM′
Z1=Φ(RAND)X=e((r−0.5σX2)(T−t)+σXT−tZ1)−1
Z2=Φ(RAND)X2=e((r−0.5σX22)(T−t)+σX2T−tX′2)−1X′2=pX1X2Z1+1−pX1X22Z2
Z3=Φ(RAND)X3=e((r−0.5σX32)(T−t)+σX3T−tX′3)−1X′3=pX1X3Z1+pX2X3Z2+1−pX1X32−pX2X32Z3
f(σM′r,T−t,P,ΔP%)=e(r−0.5σM2)(T−t)+σMT−tΦ(P)−1−ΔP%f′(σM′r,T−t,P)=((T−t)σM−T−tΦ(P))e(r−0.5σM2)(T−t)+σMT−tΦ(P)
u=eσT/nd=1/u
p=u−dernT−dQ=1−