Responsible use of any portfolio model that incorporates correlation structure requires knowledge of its sampling distribution. This is especially true of models used in stress testing, or ones requiring the specification of particular scenarios with particular correlation values (e.g. in...

We present an easily implemented, fast, and accurate method for approximating extreme quantiles of compound loss distributions (frequency and severity) as are commonly used in insurance and operational risk capital models. The Interpolated Single Loss Approximation (ISLA) of Opdyke (2014) is...

While permutation tests and bootstraps have very wide-ranging application, both share a common potential drawback: as data-intensive resampling methods, both can be runtime prohibitive when applied to large or even medium-sized data samples drawn from large datasets. The data explosion over the...

The largest US banks and Systemically Important Financial Institutions are required by regulatory mandate to estimate the operational risk capital they must hold using an Advanced Measurement Approach (AMA) as defined by the Basel II/III Accords. Most of these institutions use the Loss...

The largest US banks are required by regulatory mandate to estimate the operational risk capital they must hold using an Advanced Measurement Approach (AMA) as defined by the Basel II/III Accords. Most use the Loss Distribution Approach (LDA) which defines the aggregate loss distribution as the...

Financial institutions have invested tremendous resources to develop operational risk capital models within the framework of the Advanced Measurement Approach (AMA) of the Basel II Accord. Most of this effort has focused on satisfying evolving regulatory requirements in the near term rather than...

In operational risk measurement, the estimation of severity distribution parameters is the main driver of capital estimates, yet this remains a non-trivial challenge for many reasons. Maximum likelihood estimation (MLE) does not adequately meet this challenge because of its well-documented...

Six permutation test algorithms coded in SAS® are compared. The fastest (“OPDN”), which uses no modules beyond Base SAS®, achieves speed increases orders of magnitude faster than the relevant “built-in” SAS® procedures (over 215x faster than Proc SurveySelect, over 350x faster than...