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Some Hints for Troubleshooting. |
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1 Estimating Credit Scores with Logit. |
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Linking scores, default probabilities and observed default behavior. |
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Estimating logit coefficients in Excel. |
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Computing statistics after model estimation. |
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Interpreting regression statistics. |
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Prediction and scenario analysis. |
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Treating outliers in input variables. |
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Choosing the functional relationship between the score and explanatory variables. |
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2 The Structural Approach to Default Prediction and Valuation. |
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Default and valuation in a structural model. |
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Implementing the Merton model with a one-year horizon. |
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A solution using equity values and equity volatilities. |
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Comparing different approaches. |
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Implementing the Merton model with a T-year horizon. |
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Multi-period transitions. |
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Obtaining a generator matrix from a given transition matrix. |
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Confidence intervals with the Binomial distribution. |
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Bootstrapped confidence intervals for the hazard approach. |
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4 Prediction of Default and Transition Rates. |
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Candidate variables for prediction. |
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Predicting investment-grade default rates with linear regression. |
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Predicting investment-grade default rates with Poisson regression. |
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Backtesting the prediction models. |
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Predicting transition matrices. |
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Adjusting transition matrices. |
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Representing transition matrices with a single parameter. |
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Shifting the transition matrix. |
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Backtesting the transition forecasts. |
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5 Modeling and Estimating Default Correlations with the Asset Value Approach. |
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Default correlation, joint default probabilities and the asset value approach. |
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Calibrating the asset value approach to default experience: the method of moments. |
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Estimating asset correlation with maximum likelihood. |
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Exploring the reliability of estimators with a Monte Carlo study. |
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6 Measuring Credit Portfolio Risk with the Asset Value Approach. |
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A default mode model implemented in the spreadsheet. |
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VBA implementation of a default-mode model. |
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Assessing simulation error. |
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Exploiting portfolio structure in the VBA program. |
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First extension: Multi-factor model. |
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Second extension: t-distributed asset values. |
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Third extension: Random LGDs. |
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Fourth extension: Other risk measures. |
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Fifth extension: Multi-state modeling. |
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7 Validation of Rating Systems. |
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Cumulative accuracy profile and accuracy ratios. |
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Receiver operating characteristic (ROC). |
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Bootstrapping confidence intervals for the accuracy ratio. |
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Interpreting CAPs and ROCs. |
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Testing the calibration of rating-specific default probabilities. |
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8 Validation of Credit Portfolio Models. |
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Testing distributions with the Berkowitz test. |
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Example implementation of the Berkowitz test. |
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Representing the loss distribution. |
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Simulating the critical chi-squared value. |
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Testing modeling details: Berkowitz on subportfolios. |
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Scope and limits of the test. |
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9 Risk-Neutral Default Probabilities and Credit Default Swaps. |
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Describing the term structure of default: PDs cumulative, marginal, and seen from today. |
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From bond prices to risk-neutral default probabilities. |
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Refining the PD estimation. |
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10 Risk Analysis of Structured Credit: CDOs and First-to-Default Swaps. |
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Estimating CDO risk with Monte Carlo simulation. |
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The large homogeneous portfolio (LHP) approximation. |
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Systematic risk of CDO tranches. |
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Default times for first-to-default swaps. |
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11 Basel II and Internal Ratings. |
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Calculating capital requirements in the Internal Ratings-Based (IRB) approach. |
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Assessing a given grading structure. |
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Towards an optimal grading structure. |
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Appendix A1 Visual Basics for Applications (VBA). |
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Appendix A3 Maximum Likelihood Estimation and Newton’s Method. |
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Appendix A4 Testing and Goodness of Fit. |
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Appendix A5 User-Defined Functions. |
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