LocalVolatilityGenerationControl.java
- package org.drip.exposure.regression;
- /*
- * -*- mode: java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
- */
- /*!
- * Copyright (C) 2020 Lakshmi Krishnamurthy
- * Copyright (C) 2019 Lakshmi Krishnamurthy
- * Copyright (C) 2018 Lakshmi Krishnamurthy
- *
- * This file is part of DROP, an open-source library targeting analytics/risk, transaction cost analytics,
- * asset liability management analytics, capital, exposure, and margin analytics, valuation adjustment
- * analytics, and portfolio construction analytics within and across fixed income, credit, commodity,
- * equity, FX, and structured products. It also includes auxiliary libraries for algorithm support,
- * numerical analysis, numerical optimization, spline builder, model validation, statistical learning,
- * and computational support.
- *
- * https://lakshmidrip.github.io/DROP/
- *
- * DROP is composed of three modules:
- *
- * - DROP Product Core - https://lakshmidrip.github.io/DROP-Product-Core/
- * - DROP Portfolio Core - https://lakshmidrip.github.io/DROP-Portfolio-Core/
- * - DROP Computational Core - https://lakshmidrip.github.io/DROP-Computational-Core/
- *
- * DROP Product Core implements libraries for the following:
- * - Fixed Income Analytics
- * - Loan Analytics
- * - Transaction Cost Analytics
- *
- * DROP Portfolio Core implements libraries for the following:
- * - Asset Allocation Analytics
- * - Asset Liability Management Analytics
- * - Capital Estimation Analytics
- * - Exposure Analytics
- * - Margin Analytics
- * - XVA Analytics
- *
- * DROP Computational Core implements libraries for the following:
- * - Algorithm Support
- * - Computation Support
- * - Function Analysis
- * - Model Validation
- * - Numerical Analysis
- * - Numerical Optimizer
- * - Spline Builder
- * - Statistical Learning
- *
- * Documentation for DROP is Spread Over:
- *
- * - Main => https://lakshmidrip.github.io/DROP/
- * - Wiki => https://github.com/lakshmiDRIP/DROP/wiki
- * - GitHub => https://github.com/lakshmiDRIP/DROP
- * - Repo Layout Taxonomy => https://github.com/lakshmiDRIP/DROP/blob/master/Taxonomy.md
- * - Javadoc => https://lakshmidrip.github.io/DROP/Javadoc/index.html
- * - Technical Specifications => https://github.com/lakshmiDRIP/DROP/tree/master/Docs/Internal
- * - Release Versions => https://lakshmidrip.github.io/DROP/version.html
- * - Community Credits => https://lakshmidrip.github.io/DROP/credits.html
- * - Issues Catalog => https://github.com/lakshmiDRIP/DROP/issues
- * - JUnit => https://lakshmidrip.github.io/DROP/junit/index.html
- * - Jacoco => https://lakshmidrip.github.io/DROP/jacoco/index.html
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- *
- * You may obtain a copy of the License at
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- /**
- * <i>LocalVolatilityGenerationControl</i> holds the Parameters the control the Calculation of the Local
- * Volatility in the Pykhtin (2009) Brownian Bridge Calibration. The References are:
- *
- * <br><br>
- * <ul>
- * <li>
- * Andersen, L. B. G., M. Pykhtin, and A. Sokol (2017): Re-thinking Margin Period of Risk
- * https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2902737 <b>eSSRN</b>
- * </li>
- * <li>
- * Andersen, L. B. G., M. Pykhtin, and A. Sokol (2017): Credit Exposure in the Presence of
- * Initial Margin https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2806156 <b>eSSRN</b>
- * </li>
- * <li>
- * Albanese, C., and L. Andersen (2014): Accounting for OTC Derivatives: Funding Adjustments and
- * the Re-Hypothecation Option https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2482955
- * <b>eSSRN</b>
- * </li>
- * <li>
- * Burgard, C., and M. Kjaer (2017): Derivatives Funding, Netting, and Accounting
- * https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2534011 <b>eSSRN</b>
- * </li>
- * <li>
- * Piterbarg, V. (2010): Funding Beyond Discounting: Collateral Agreements and Derivatives
- * Pricing <i>Risk</i> <b>21 (2)</b> 97-102
- * </li>
- * </ul>
- *
- * <br><br>
- * <ul>
- * <li><b>Module </b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/PortfolioCore.md">Portfolio Core Module</a></li>
- * <li><b>Library</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/ExposureAnalyticsLibrary.md">Exposure Analytics</a></li>
- * <li><b>Project</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/exposure/README.md">Exposure Group Level Collateralized/Uncollateralized Exposure</a></li>
- * <li><b>Package</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/exposure/regression/README.md">Regression Based Path Exposure Generation</a></li>
- * </ul>
- *
- * @author Lakshmi Krishnamurthy
- */
- public class LocalVolatilityGenerationControl
- {
- /**
- * The Pyhktin (2009) Empirical Floor
- */
- public static final int PYKHTIN_2009_EMPIRICAL_FLOOR = 20;
- /**
- * The Pyhktin (2009) Empirical Ceiling Factor
- */
- public static final double PYKHTIN_2009_EMPIRICAL_CEILING_FACTOR = 0.05;
- /**
- * The Local Volatility Smooth Floor Bias
- */
- public static final double LOCAL_VOLATILITY_SMOOTHING_FLOOR_BIAS = 0.90;
- private double[] _uniformCPDArray = null;
- private int _localVolatilityIndexShift = -1;
- private double[] _impliedBrownianVariateArray = null;
- private org.drip.spline.params.SegmentCustomBuilderControl[] _segmentCustomBuilderControlArray = null;
- /**
- * Construct a Standard Instance of LocalVolatilityGenerationControl
- *
- * @param ensembleSize Size of the Distribution Ensemble
- *
- * @return Standard Instance of LocalVolatilityGenerationControl
- */
- public static final LocalVolatilityGenerationControl Standard (
- final int ensembleSize)
- {
- if (PYKHTIN_2009_EMPIRICAL_FLOOR > ensembleSize)
- {
- return null;
- }
- double[] uniformCPDArray = new double[ensembleSize];
- double[] impliedBrownianVariateArray = new double[ensembleSize];
- int localVolatilityIndexShift = (int) (LOCAL_VOLATILITY_SMOOTHING_FLOOR_BIAS *
- PYKHTIN_2009_EMPIRICAL_FLOOR + (1 - LOCAL_VOLATILITY_SMOOTHING_FLOOR_BIAS) * ensembleSize);
- if (PYKHTIN_2009_EMPIRICAL_FLOOR > localVolatilityIndexShift)
- {
- return null;
- }
- for (int realizationCoordinate = 0;
- realizationCoordinate < ensembleSize;
- ++realizationCoordinate)
- {
- try
- {
- impliedBrownianVariateArray[realizationCoordinate] =
- org.drip.measure.gaussian.NormalQuadrature.InverseCDF
- (uniformCPDArray[realizationCoordinate] = (((double) realizationCoordinate) + 0.5) /
- ((double) ensembleSize));
- }
- catch (java.lang.Exception e)
- {
- e.printStackTrace();
- return null;
- }
- }
- try
- {
- org.drip.spline.params.SegmentCustomBuilderControl[] segmentCustomBuilderControlArray = new
- org.drip.spline.params.SegmentCustomBuilderControl[ensembleSize - 1];
- org.drip.spline.params.SegmentCustomBuilderControl segmentCustomBuilderControl = new
- org.drip.spline.params.SegmentCustomBuilderControl (
- org.drip.spline.stretch.MultiSegmentSequenceBuilder.BASIS_SPLINE_POLYNOMIAL,
- new org.drip.spline.basis.PolynomialFunctionSetParams (2),
- org.drip.spline.params.SegmentInelasticDesignControl.Create (
- 0,
- 2
- ),
- new org.drip.spline.params.ResponseScalingShapeControl (
- true,
- new org.drip.function.r1tor1.QuadraticRationalShapeControl (0.)
- ),
- null
- );
- for (int realizationCoordinate = 0;
- realizationCoordinate < ensembleSize - 1;
- ++realizationCoordinate)
- {
- segmentCustomBuilderControlArray[realizationCoordinate] = segmentCustomBuilderControl;
- }
- return new LocalVolatilityGenerationControl (
- localVolatilityIndexShift,
- uniformCPDArray,
- impliedBrownianVariateArray,
- segmentCustomBuilderControlArray
- );
- }
- catch (java.lang.Exception e)
- {
- e.printStackTrace();
- }
- return null;
- }
- /**
- * LocalVolatilityGenerationControl Constructor
- *
- * @param localVolatilityIndexShift The Local Volatility Index Shift
- * @param uniformCPDArray The Uniform Cumulative Probability Density Array
- * @param impliedBrownianVariateArray The Implied Brownian Variate Array
- * @param segmentCustomBuilderControlArray Array of Segment Builder Control
- *
- * @throws java.lang.Exception Thrown if the Inputs are Invalid
- */
- public LocalVolatilityGenerationControl (
- final int localVolatilityIndexShift,
- final double[] uniformCPDArray,
- final double[] impliedBrownianVariateArray,
- final org.drip.spline.params.SegmentCustomBuilderControl[] segmentCustomBuilderControlArray)
- throws java.lang.Exception
- {
- if (0 >= (_localVolatilityIndexShift = localVolatilityIndexShift) ||
- null == (_uniformCPDArray = uniformCPDArray) ||
- null == (_impliedBrownianVariateArray = impliedBrownianVariateArray) ||
- null == (_segmentCustomBuilderControlArray = segmentCustomBuilderControlArray))
- {
- throw new java.lang.Exception ("LocalVolatilityGenerationControl Constructor => Invalid Inputs");
- }
- int uniformCPDArraySize = _uniformCPDArray.length;
- if (0 == uniformCPDArraySize ||
- uniformCPDArraySize != _impliedBrownianVariateArray.length ||
- uniformCPDArraySize != _segmentCustomBuilderControlArray.length + 1)
- {
- throw new java.lang.Exception ("LocalVolatilityGenerationControl Constructor => Invalid Inputs");
- }
- }
- /**
- * Retrieve the Local Volatility Index Shift
- *
- * @return The Local Volatility Index Shift
- */
- public int localVolatilityIndexShift()
- {
- return _localVolatilityIndexShift;
- }
- /**
- * Retrieve the Uniform Cumulative Probability Density Array
- *
- * @return The Uniform Cumulative Probability Density Array
- */
- public double[] uniformCPDArray()
- {
- return _uniformCPDArray;
- }
- /**
- * Retrieve the Implied Brownian Variate Array
- *
- * @return The Implied Brownian Variate Array
- */
- public double[] impliedBrownianVariateArray()
- {
- return _impliedBrownianVariateArray;
- }
- /**
- * Retrieve the Custom Segment Builder Control Array
- *
- * @return The Custom Segment Builder Control Array
- */
- public org.drip.spline.params.SegmentCustomBuilderControl[] segmentCustomBuilderControlArray()
- {
- return _segmentCustomBuilderControlArray;
- }
- }