moreGreeks.strikeSensitivity = black.strikeSensitivity();
moreGreeks.itmCashProbability = black.itmCashProbability();
} else {
// early exercise can be optimal
final CumulativeNormalDistribution cumNormalDist = new CumulativeNormalDistribution();
final NormalDistribution normalDist = new NormalDistribution();
final double /*@Real*/ tolerance = 1e-6;
final double /*@Real*/ Sk = BaroneAdesiWhaleyApproximationEngine.criticalPrice(payoff, riskFreeDiscount, dividendDiscount, variance, tolerance);
final double /*@Real*/ forwardSk = Sk * dividendDiscount / riskFreeDiscount;
final double /*@Real*/ alpha = -2.0*Math.log(riskFreeDiscount)/(variance);
final double /*@Real*/ beta = 2.0*Math.log(dividendDiscount/riskFreeDiscount)/
(variance);
final double /*@Real*/ h = 1 - riskFreeDiscount;
double /*@Real*/ phi;
switch (payoff.optionType()) {
case Call:
phi = 1;
break;
case Put:
phi = -1;
break;
default:
throw new LibraryException(UNKNOWN_OPTION_TYPE); // QA:[RG]::verified
}
// TODO: study how zero interest rate could be handled
QL.ensure(h != 0.0 , DIVIDING_BY_ZERO_INTEREST_RATE); // QA:[RG]::verified
final double /* @Real */temp_root = Math.sqrt((beta - 1) * (beta - 1) + (4 * alpha) / h);
final double /* @Real */lambda = (-(beta - 1) + phi * temp_root) / 2;
final double /* @Real */lambda_prime = -phi * alpha / (h * h * temp_root);
final double /* @Real */black_Sk = BlackFormula.blackFormula(payoff.optionType(), payoff.strike(), forwardSk, Math.sqrt(variance)) * riskFreeDiscount;
final double /* @Real */hA = phi * (Sk - payoff.strike()) - black_Sk;
final double /* @Real */d1_Sk = (Math.log(forwardSk / payoff.strike()) + 0.5 * variance) / Math.sqrt(variance);
final double /* @Real */d2_Sk = d1_Sk - Math.sqrt(variance);
final double /* @Real */part1 = forwardSk * normalDist.op(d1_Sk) / (alpha * Math.sqrt(variance));
final double /* @Real */part2 = -phi * forwardSk * cumNormalDist.op(phi * d1_Sk) * Math.log(dividendDiscount) / Math.log(riskFreeDiscount);
final double /* @Real */part3 = +phi * payoff.strike() * cumNormalDist.op(phi * d2_Sk);
final double /* @Real */V_E_h = part1 + part2 + part3;
final double /* @Real */b = (1 - h) * alpha * lambda_prime / (2 * (2 * lambda + beta - 1));
final double /* @Real */c = -((1 - h) * alpha / (2 * lambda + beta - 1)) * (V_E_h / (hA) + 1 / h + lambda_prime / (2 * lambda + beta - 1));
final double /* @Real */temp_spot_ratio = Math.log(spot / Sk);
final double /* @Real */chi = temp_spot_ratio * (b * temp_spot_ratio + c);
if (phi * (Sk - spot) > 0) {
r.value = black.value() + hA * Math.pow((spot / Sk), lambda) / (1 - chi);
} else {
r.value = phi * (spot - payoff.strike());
}
final double /* @Real */temp_chi_prime = (2 * b / spot) * Math.log(spot / Sk);
final double /* @Real */chi_prime = temp_chi_prime + c / spot;
final double /* @Real */chi_double_prime = 2 * b / (spot * spot) - temp_chi_prime / spot - c / (spot * spot);
greeks.delta = phi * dividendDiscount * cumNormalDist.op(phi * d1_Sk)
+ (lambda / (spot * (1 - chi)) + chi_prime / ((1 - chi)*(1 - chi))) *
(phi * (Sk - payoff.strike()) - black_Sk) * Math.pow((spot/Sk), lambda);
greeks.gamma = phi * dividendDiscount * normalDist.op(phi*d1_Sk) /
(spot * Math.sqrt(variance))
+ (2 * lambda * chi_prime / (spot * (1 - chi) * (1 - chi))
+ 2 * chi_prime * chi_prime / ((1 - chi) * (1 - chi) * (1 - chi))
+ chi_double_prime / ((1 - chi) * (1 - chi))
+ lambda * (1 - lambda) / (spot * spot * (1 - chi)))