Requirements for modelling specific risk
Article 370
An internal model used for calculating own funds requirements for specific risk and an internal model for correlation trading shall meet the following additional requirements: (a) it explains the historical price variation in the portfolio; (b) it captures concentration in terms of magnitude and changes of composition of the portfolio; (c) it is robust to an adverse environment; (d) it is validated through back-testing aimed at assessing whether specific risk is being accurately captured. If the institution performs such back-testing on the basis of relevant sub-portfolios, these shall be chosen in a consistent manner; (e) it captures name-related basis risk and shall in particular be sensitive to material idiosyncratic differences between similar but not identical positions; (f) it captures event risk.