Appendix A
Economic Capital Allocation Approaches
Assume a loss distribution defined by L and a certain quantile α. The credit value at risk (CVaR) associated with the quantile is defined respectively as:
(A.1)
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Below we will define approaches using standard risk measures that are largely used in practice for allocating economic capital. Assume the conglomerate is comprised of n subportfolios whose allocations we want to determine. Below we show some of the different approaches used for ECAP allocation with some comments on the differences:
1. VaR / Covar. Although largely used by practitioners, this approach is typical for Gaussian loss distribution. The allocated capital of a certain subportfolio is given by:
(A.2)
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where Li and L are the losses of the subportfolio i and the total portfolio respectively. ECAPT(α) and361are the total ECAP of the portfolio at the quantile α, and the total portfolio loss variance respectively.
2. Pro-rata CVaR. In this approach one uses the stand-alone CVaRα of each sub-portfolio as a weight in the allocation of the total risk:3
(A.3)
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3. Basel II. In this approach ...

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