CurvatureEstimatorResponseFunction.java

  1. package org.drip.simm.foundation;

  2. /*
  3.  * -*- mode: java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  4.  */

  5. /*!
  6.  * Copyright (C) 2020 Lakshmi Krishnamurthy
  7.  * Copyright (C) 2019 Lakshmi Krishnamurthy
  8.  * Copyright (C) 2018 Lakshmi Krishnamurthy
  9.  *
  10.  *  This file is part of DROP, an open-source library targeting analytics/risk, transaction cost analytics,
  11.  *      asset liability management analytics, capital, exposure, and margin analytics, valuation adjustment
  12.  *      analytics, and portfolio construction analytics within and across fixed income, credit, commodity,
  13.  *      equity, FX, and structured products. It also includes auxiliary libraries for algorithm support,
  14.  *      numerical analysis, numerical optimization, spline builder, model validation, statistical learning,
  15.  *      and computational support.
  16.  *  
  17.  *      https://lakshmidrip.github.io/DROP/
  18.  *  
  19.  *  DROP is composed of three modules:
  20.  *  
  21.  *  - DROP Product Core - https://lakshmidrip.github.io/DROP-Product-Core/
  22.  *  - DROP Portfolio Core - https://lakshmidrip.github.io/DROP-Portfolio-Core/
  23.  *  - DROP Computational Core - https://lakshmidrip.github.io/DROP-Computational-Core/
  24.  *
  25.  *  DROP Product Core implements libraries for the following:
  26.  *  - Fixed Income Analytics
  27.  *  - Loan Analytics
  28.  *  - Transaction Cost Analytics
  29.  *
  30.  *  DROP Portfolio Core implements libraries for the following:
  31.  *  - Asset Allocation Analytics
  32.  *  - Asset Liability Management Analytics
  33.  *  - Capital Estimation Analytics
  34.  *  - Exposure Analytics
  35.  *  - Margin Analytics
  36.  *  - XVA Analytics
  37.  *
  38.  *  DROP Computational Core implements libraries for the following:
  39.  *  - Algorithm Support
  40.  *  - Computation Support
  41.  *  - Function Analysis
  42.  *  - Model Validation
  43.  *  - Numerical Analysis
  44.  *  - Numerical Optimizer
  45.  *  - Spline Builder
  46.  *  - Statistical Learning
  47.  *
  48.  *  Documentation for DROP is Spread Over:
  49.  *
  50.  *  - Main                     => https://lakshmidrip.github.io/DROP/
  51.  *  - Wiki                     => https://github.com/lakshmiDRIP/DROP/wiki
  52.  *  - GitHub                   => https://github.com/lakshmiDRIP/DROP
  53.  *  - Repo Layout Taxonomy     => https://github.com/lakshmiDRIP/DROP/blob/master/Taxonomy.md
  54.  *  - Javadoc                  => https://lakshmidrip.github.io/DROP/Javadoc/index.html
  55.  *  - Technical Specifications => https://github.com/lakshmiDRIP/DROP/tree/master/Docs/Internal
  56.  *  - Release Versions         => https://lakshmidrip.github.io/DROP/version.html
  57.  *  - Community Credits        => https://lakshmidrip.github.io/DROP/credits.html
  58.  *  - Issues Catalog           => https://github.com/lakshmiDRIP/DROP/issues
  59.  *  - JUnit                    => https://lakshmidrip.github.io/DROP/junit/index.html
  60.  *  - Jacoco                   => https://lakshmidrip.github.io/DROP/jacoco/index.html
  61.  *
  62.  *  Licensed under the Apache License, Version 2.0 (the "License");
  63.  *      you may not use this file except in compliance with the License.
  64.  *  
  65.  *  You may obtain a copy of the License at
  66.  *      http://www.apache.org/licenses/LICENSE-2.0
  67.  *  
  68.  *  Unless required by applicable law or agreed to in writing, software
  69.  *      distributed under the License is distributed on an "AS IS" BASIS,
  70.  *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  71.  *  
  72.  *  See the License for the specific language governing permissions and
  73.  *      limitations under the License.
  74.  */

  75. /**
  76.  * <i>CurvatureEstimatorResponseFunction</i> estimates the Curvature Margin from the Curvature Sensitivities
  77.  * using the Curvature Response Function. The References are:
  78.  *
  79.  * <br><br>
  80.  *  <ul>
  81.  *      <li>
  82.  *          Andersen, L. B. G., M. Pykhtin, and A. Sokol (2017): Credit Exposure in the Presence of Initial
  83.  *              Margin https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2806156 <b>eSSRN</b>
  84.  *      </li>
  85.  *      <li>
  86.  *          Albanese, C., S. Caenazzo, and O. Frankel (2017): Regression Sensitivities for Initial Margin
  87.  *              Calculations https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2763488 <b>eSSRN</b>
  88.  *      </li>
  89.  *      <li>
  90.  *          Anfuso, F., D. Aziz, P. Giltinan, and K. Loukopoulus (2017): A Sound Modeling and Back-testing
  91.  *              Framework for Forecasting Initial Margin Requirements
  92.  *                  https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2716279 <b>eSSRN</b>
  93.  *      </li>
  94.  *      <li>
  95.  *          Caspers, P., P. Giltinan, R. Lichters, and N. Nowaczyk (2017): Forecasting Initial Margin
  96.  *              Requirements - A Model Evaluation https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2911167
  97.  *                  <b>eSSRN</b>
  98.  *      </li>
  99.  *      <li>
  100.  *          International Swaps and Derivatives Association (2017): SIMM v2.0 Methodology
  101.  *              https://www.isda.org/a/oFiDE/isda-simm-v2.pdf
  102.  *      </li>
  103.  *  </ul>
  104.  *
  105.  * <br><br>
  106.  *  <ul>
  107.  *      <li><b>Module </b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/PortfolioCore.md">Portfolio Core Module</a></li>
  108.  *      <li><b>Library</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/MarginAnalyticsLibrary.md">Initial and Variation Margin Analytics</a></li>
  109.  *      <li><b>Project</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/simm/README.md">Initial Margin Analytics based on ISDA SIMM and its Variants</a></li>
  110.  *      <li><b>Package</b> = <a href = "https://github.com/lakshmiDRIP/DROP/tree/master/src/main/java/org/drip/simm/foundation/README.md">Foundation Utilities for ISDA SIMM</a></li>
  111.  *  </ul>
  112.  * <br><br>
  113.  *
  114.  * @author Lakshmi Krishnamurthy
  115.  */

  116. public class CurvatureEstimatorResponseFunction implements org.drip.simm.foundation.CurvatureEstimator
  117. {
  118.     private org.drip.simm.foundation.CurvatureResponse _curvatureResponse = null;

  119.     /**
  120.      * Construct the Cornish Fischer Instance of the Curvature Estimator
  121.      *
  122.      * @return The Cornish Fischer Instance of the Curvature Estimator
  123.      */

  124.     public static final CurvatureEstimatorResponseFunction CornishFischer()
  125.     {
  126.         try
  127.         {
  128.             return new CurvatureEstimatorResponseFunction
  129.                 (org.drip.simm.foundation.CurvatureResponseCornishFischer.Standard());
  130.         }
  131.         catch (java.lang.Exception e)
  132.         {
  133.             e.printStackTrace();
  134.         }

  135.         return null;
  136.     }

  137.     /**
  138.      * CurvatureEstimatorResponseFunction Constructor
  139.      *
  140.      * @param curvatureResponse The Curvature Response Function
  141.      *
  142.      * @throws java.lang.Exception Thrown if the Inputs are Invalid
  143.      */

  144.     public CurvatureEstimatorResponseFunction (
  145.         final org.drip.simm.foundation.CurvatureResponse curvatureResponse)
  146.         throws java.lang.Exception
  147.     {
  148.         if (null == (_curvatureResponse = curvatureResponse))
  149.         {
  150.             throw new java.lang.Exception
  151.                 ("CurvatureEstimatorResponseFunction Constructor => Invalid Inputs");
  152.         }
  153.     }

  154.     /**
  155.      * Retrieve the Curvature Response Function
  156.      *
  157.      * @return The Curvature Response Function
  158.      */

  159.     public org.drip.simm.foundation.CurvatureResponse curvatureResponse()
  160.     {
  161.         return _curvatureResponse;
  162.     }

  163.     @Override public double margin (
  164.         final double cumulativeRiskFactorSensitivity,
  165.         final double cumulativeRiskFactorSensitivityPositive,
  166.         final double riskFactorSensitivityVariance)
  167.         throws java.lang.Exception
  168.     {
  169.         if (!org.drip.numerical.common.NumberUtil.IsValid (riskFactorSensitivityVariance) ||
  170.             0. > riskFactorSensitivityVariance)
  171.         {
  172.             throw new java.lang.Exception ("CurvatureEstimatorResponseFunction::margin => Invalid Inputs");
  173.         }

  174.         return java.lang.Math.max (
  175.             cumulativeRiskFactorSensitivity +
  176.                 _curvatureResponse.lambda (
  177.                     cumulativeRiskFactorSensitivity,
  178.                     cumulativeRiskFactorSensitivityPositive
  179.                 ) * java.lang.Math.sqrt (riskFactorSensitivityVariance),
  180.             0.
  181.         );
  182.     }

  183.     @Override public boolean isCorrelatorQuadratric()
  184.     {
  185.         return true;
  186.     }

  187.     @Override public double varianceModulator (
  188.         final java.lang.String bucketKey1,
  189.         final double bucketVariance1,
  190.         final java.lang.String bucketKey2,
  191.         final double bucketVariance2)
  192.         throws java.lang.Exception
  193.     {
  194.         return 1.;
  195.     }
  196. }