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3.7 Independent Validation

3.7.1
 
The independent validation must be established as a key step of the model lifecycle management and is the basis upon which Model Risk can be assessed and managed. Institutions must implement a process to validate independently all their models on a regular basis based on model types, as part of their model life-cycle management. Minimum frequencies are mentioned in Part II of the MMS.
 
3.7.2
 
In the context of model management, the model owner acts as the first line of defence, the independent validator acts as a the second line of defence and the internal audit function acts as the third line of defence.
 
3.7.3
 
The validation process must be organised with specific responsibilities, metrics, limits and reporting requirements for each model type. The validation process must be constructed to ensure an effective identification and remediation of model defects to manage Model Risk appropriately. This is referred to as the Effective Challenge principle.
 
3.7.4
 
Model validation can be performed either by an internal independent team or by a third party. In all cases, the validation process must remain independent from the development process. If model validation is assigned to a third party, institutions remain the owners of validation reports and remain responsible for taking appropriate actions upon the issuance of these reports. If the institution has an internal validation team and also uses third party validators, the internal validation team must maintain oversight of all validation exercises conducted by third parties. If the institution does not have an internal validation team, all validation reports produced by third parties should be owned by an appropriate internal control function separate from the model owner.
 
3.7.5
 
The validation must be independent by virtue of excluding the development team from involvement in the assessment of the model. The development team may be involved in the validation process once a set of observations has been produced, in particular for the remediation of these observations. Institutions must be able to demonstrate to the Central Bank, the appropriate arm’s length independence of the validator. Consequently, if a third party provides a methodology to develop a model for an institution, any subsequent validation exercise must be performed by a party different from the original provider. Validation teams must not report to the business lines.
 
3.7.6
 
The validation team must possess sufficient technical skills and maturity to formally express its opinion without the interference of the development team or from the business lines. The business lines may be consulted during the validation process, but the conclusion of such process must be formed independently from business line interests.
 
3.7.7
 
The validation scope must cover both a qualitative validation and a quantitative validation. A qualitative validation alone is not sufficient to be considered as a complete validation. If insufficient data is available to perform the quantitative validation of a model, the validation process must be flagged as incomplete and the institution must recognise and account for the uncertainty and thus the Model Risk related to such model.
 
3.7.8
 
A validation exercise must result in a full articulated judgement regarding the suitability of the model to support decision-making. The analyses and tests performed during the validation of a model must be rigorously documented in a validation report, such that (i) management is able to form a view on the performance of the model, and (ii) an independent party is able to repeat the process on the basis of the report.
 
3.7.9
 
Institutions must put in place an effective process to manage and remedy findings arising from validation exercises. Observations and findings across all models must be documented, recorded, tracked and reported to Senior Management and the Board at least once a year. Findings must be classified into groups based on their associated severity, in order to drive the prioritisation of remediation.
 
3.7.10
 
Institutions must ensure that model defects are understood and remedied within an appropriate time-frame. They must implement an effective process to prioritise and address model defects based on their materiality and/or associated Model Risk. High severity findings must be remedied promptly. If necessary, such remediation may rely on temporary adjustments and/or manual override. Such adjustments and overrides must not become regular practice, in that they must have an expiry horizon and must be coupled with a plan to implement more robust remediation. Further requirements and minimum remediation timings are mentioned in Part II.
 
3.7.11
 
Models employed by institutions must be fit for purpose to support decision-making. Therefore, institutions must aim to resolve all model defects associated with high and medium severity and aim to minimise the number of defects with low severity. If an institution decides not to address some model defects, it must identify, assess and report the associated Model Risk to Senior Management and the Board. Such decision may result in additional provisions and/or capital buffers and will be subject to review by the CBUAE.
 
3.7.12
 
The internal audit function is responsible for verifying that the model validation process is performed appropriately and meets the MMS requirements. This review must be planned as part of regular audit cycles. The audit team must comment on the degree of independence of the internal validation process. For technical matters, the audit team may decide to be assisted by third party experts. Where third party assistance is utilised, the internal audit function remains the sole owner of the conclusions of the audit report.