//-------------------------------------------------------------------------
/// <summary>
/// Calculates the present value sensitivity of the swaption product to the rate curves.
/// <para>
/// The present value sensitivity is computed in a "sticky model parameter" style, i.e. the sensitivity to the
/// curve nodes with the SABR model parameters unchanged. This sensitivity does not include a potential
/// re-calibration of the model parameters to the raw market data.
///
/// </para>
/// </summary>
/// <param name="swaption"> the swaption product </param>
/// <param name="ratesProvider"> the rates provider </param>
/// <param name="swaptionVolatilities"> the volatilities </param>
/// <returns> the point sensitivity to the rate curves </returns>
public virtual PointSensitivityBuilder presentValueSensitivityRatesStickyModel(ResolvedSwaption swaption, RatesProvider ratesProvider, SabrSwaptionVolatilities swaptionVolatilities)
{
validate(swaption, ratesProvider, swaptionVolatilities);
ZonedDateTime expiryDateTime = swaption.Expiry;
double expiry = swaptionVolatilities.relativeTime(expiryDateTime);
ResolvedSwap underlying = swaption.Underlying;
ResolvedSwapLeg fixedLeg = this.fixedLeg(underlying);
if (expiry < 0d)
{ // Option has expired already
return(PointSensitivityBuilder.none());
}
double forward = SwapPricer.parRate(underlying, ratesProvider);
ValueDerivatives annuityDerivative = SwapPricer.LegPricer.annuityCashDerivative(fixedLeg, forward);
double annuityCash = annuityDerivative.Value;
double annuityCashDr = annuityDerivative.getDerivative(0);
LocalDate settlementDate = ((CashSwaptionSettlement)swaption.SwaptionSettlement).SettlementDate;
double discountSettle = ratesProvider.discountFactor(fixedLeg.Currency, settlementDate);
double strike = calculateStrike(fixedLeg);
double tenor = swaptionVolatilities.tenor(fixedLeg.StartDate, fixedLeg.EndDate);
double shift = swaptionVolatilities.shift(expiry, tenor);
ValueDerivatives volatilityAdj = swaptionVolatilities.volatilityAdjoint(expiry, tenor, strike, forward);
bool isCall = fixedLeg.PayReceive.Pay;
double shiftedForward = forward + shift;
double shiftedStrike = strike + shift;
double price = BlackFormulaRepository.price(shiftedForward, shiftedStrike, expiry, volatilityAdj.Value, isCall);
double delta = BlackFormulaRepository.delta(shiftedForward, shiftedStrike, expiry, volatilityAdj.Value, isCall);
double vega = BlackFormulaRepository.vega(shiftedForward, shiftedStrike, expiry, volatilityAdj.Value);
PointSensitivityBuilder forwardSensi = SwapPricer.parRateSensitivity(underlying, ratesProvider);
PointSensitivityBuilder discountSettleSensi = ratesProvider.discountFactors(fixedLeg.Currency).zeroRatePointSensitivity(settlementDate);
double sign = swaption.LongShort.sign();
return(forwardSensi.multipliedBy(sign * discountSettle * (annuityCash * (delta + vega * volatilityAdj.getDerivative(0)) + annuityCashDr * price)).combinedWith(discountSettleSensi.multipliedBy(sign * annuityCash * price)));
}
/// <summary>
/// Calculates the delta of the bond future option product based on the price of the underlying future.
/// <para>
/// The delta of the product is the sensitivity of the option price to the future price.
/// The volatility is unchanged for a fixed strike in the sensitivity computation, hence the "StickyStrike" name.
///
/// </para>
/// </summary>
/// <param name="futureOption"> the option product </param>
/// <param name="discountingProvider"> the discounting provider </param>
/// <param name="volatilities"> the volatilities </param>
/// <param name="futurePrice"> the price of the underlying future </param>
/// <returns> the price curve sensitivity of the product </returns>
public double deltaStickyStrike(ResolvedBondFutureOption futureOption, LegalEntityDiscountingProvider discountingProvider, BlackBondFutureVolatilities volatilities, double futurePrice)
{
ArgChecker.isTrue(futureOption.PremiumStyle.Equals(FutureOptionPremiumStyle.DAILY_MARGIN), "Premium style should be DAILY_MARGIN");
double strike = futureOption.StrikePrice;
ResolvedBondFuture future = futureOption.UnderlyingFuture;
double volatility = volatilities.volatility(futureOption.Expiry, future.LastTradeDate, strike, futurePrice);
double timeToExpiry = volatilities.relativeTime(futureOption.Expiry);
double delta = BlackFormulaRepository.delta(futurePrice, strike, timeToExpiry, volatility, futureOption.PutCall.Call);
return(delta);
}
//-------------------------------------------------------------------------
public virtual void test_delta_presentValueDelta()
{
double deltaCall = PRICER.delta(CALL_OTM, RATES_PROVIDER, VOLS);
CurrencyAmount pvDeltaCall = PRICER.presentValueDelta(CALL_OTM, RATES_PROVIDER, VOLS);
double deltaPut = PRICER.delta(PUT_ITM, RATES_PROVIDER, VOLS);
CurrencyAmount pvDeltaPut = PRICER.presentValueDelta(PUT_ITM, RATES_PROVIDER, VOLS);
double timeToExpiry = VOLS.relativeTime(EXPIRY);
double dfFor = RATES_PROVIDER.discountFactor(EUR, PAYMENT_DATE);
double forward = PRICER.DiscountingFxSingleProductPricer.forwardFxRate(FX_PRODUCT_HIGH, RATES_PROVIDER).fxRate(CURRENCY_PAIR);
double vol = SMILE_TERM.volatility(timeToExpiry, STRIKE_RATE_HIGH, forward);
double expectedDeltaCall = dfFor * BlackFormulaRepository.delta(forward, STRIKE_RATE_HIGH, timeToExpiry, vol, true);
double expectedDeltaPut = dfFor * BlackFormulaRepository.delta(forward, STRIKE_RATE_HIGH, timeToExpiry, vol, false);
double expectedPvDeltaCall = -NOTIONAL *dfFor *BlackFormulaRepository.delta(forward, STRIKE_RATE_HIGH, timeToExpiry, vol, true);
double expectedPvDeltaPut = NOTIONAL * dfFor * BlackFormulaRepository.delta(forward, STRIKE_RATE_HIGH, timeToExpiry, vol, false);
assertEquals(deltaCall, expectedDeltaCall, TOL);
assertEquals(pvDeltaCall.Currency, USD);
assertEquals(pvDeltaCall.Amount, expectedPvDeltaCall, NOTIONAL * TOL);
assertEquals(deltaPut, expectedDeltaPut, TOL);
assertEquals(pvDeltaPut.Currency, USD);
assertEquals(pvDeltaPut.Amount, expectedPvDeltaPut, NOTIONAL * TOL);
}
public virtual void test_presentValueDelta_formula_shift()
{
CurrencyAmount computedCaplet = PRICER.presentValueDelta(CAPLET_LONG, RATES, SHIFTED_VOLS);
CurrencyAmount computedFloorlet = PRICER.presentValueDelta(FLOORLET_SHORT, RATES, SHIFTED_VOLS);
double forward = RATES.iborIndexRates(EUR_EURIBOR_3M).rate(RATE_COMP.Observation);
double expiry = SHIFTED_VOLS.relativeTime(CAPLET_LONG.FixingDateTime);
double volatility = SHIFTED_VOLS.volatility(expiry, STRIKE, forward);
double df = RATES.discountFactor(EUR, CAPLET_LONG.PaymentDate);
double shift = IborCapletFloorletDataSet.SHIFT;
double expectedCaplet = NOTIONAL * df * CAPLET_LONG.YearFraction * BlackFormulaRepository.delta(forward + shift, STRIKE + shift, expiry, volatility, true);
double expectedFloorlet = -NOTIONAL *df *FLOORLET_SHORT.YearFraction *BlackFormulaRepository.delta(forward + shift, STRIKE + shift, expiry, volatility, false);
assertEquals(computedCaplet.Currency, EUR);
assertEquals(computedCaplet.Amount, expectedCaplet, NOTIONAL * TOL);
assertEquals(computedFloorlet.Currency, EUR);
assertEquals(computedFloorlet.Amount, expectedFloorlet, NOTIONAL * TOL);
}
