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Pierre Leignadier / Yihui Zhang OMNIMARKETS, LLC | 160 BROADWAY, SUITE 700, NEW YORK, NY 10038, USA
Model Risk Management BEST PRACTICES FOR TODAY AND TOMORROW
November 2016.
Model Risk Management. Best Practices for today and tomorrow.
1 OmniMarkets, LLC.
Abstract
We review the development of model risk management against the backdrop of
the growing importance of models in the financial industry, in terms of number,
use and complexity. Our collective understanding of the means to mitigate model
risk have evolved and so has the regulations. The first publication on the matter
(OCC 2000-16) focuses on Model Validation mainly, ten years later it was followed
by a more comprehensive set of guidance and recommendations (OCC 2011-12 /
SR 11-7) “Supervisory Guidance on Model Risk Management”. Model Risk
Management (“MRM”) is still maturing today but its importance will undoubtedly
continue to grow; so we have sought to extract the best lessons applicable today as
well as to peek into the future.
Disclaimer
All of the views, opinions and interpretations presented herein are solely those of
OmniMarkets and should not in any way be considered to represent those of the
Office of Comptroller of the Currency or of the Federal Reserve.
Model Risk Management. Best Practices for today and tomorrow.
2 OmniMarkets, LLC.
Table of Contents
Abstract ....................................................................................................................... 1
Disclaimer ................................................................................................................... 1
Table of Contents ........................................................................................................ 2
Introduction ................................................................................................................ 3
1 Regulatory Requirements and Best Practices..................................................... 4
1.1 Bulletin OCC 2000-16: a new millennium for Model Risk Management ..... 4
1.1.1 Key points of OCC-2000 ........................................................................... 4
1.1.2 Sound Model Validation policy ............................................................... 5
1.1.3 Model Validation procedure ................................................................... 6
1.2 OCC Bulletin 2011-12 replaces 2000-16 – Key points: ................................. 8
1.2.1 OCC 2011-12/SR 11-7 - The role of Internal Audit .................................. 8
1.2.2 Model Validation – Best practice elements ............................................ 9
2 Model Risk Management today ....................................................................... 10
2.1 Model development ................................................................................... 10
2.2 Model Validation ........................................................................................ 10
2.3 On-going monitoring .................................................................................. 10
2.4 Models Inventory ....................................................................................... 11
3 Raising the bar: “M” is for Management .......................................................... 12
3.1 Holistic MRM .............................................................................................. 12
3.2 Governance = workflows ........................................................................... 14
3.3 Interactions between models .................................................................... 14
4 Quantifying Model Risk .................................................................................... 16
4.1 Measurement of MRM – 1st Generation: KPI ............................................. 16
4.2 Measurement of MRM – 2nd Generation: PE, EAE and LGE ..................... 16
References ................................................................................................................ 18
OmniMarkets – Senior Team .................................................................................... 19
Model Risk Management. Best Practices for today and tomorrow.
3 OmniMarkets, LLC.
Introduction
The concept of Model Risk, the need for its recognition and management did not
really exist prior to the 1990’s. This is understandable, as any model error made by
a person could only have a (very) limited impact and hence, there was no real
model risk per se. The advent of computers in banks changed that forever. The
same model, the very same algorithm is now being used a staggering amount of
times, with ever increasing volumes and more and more automation (increasing
the multiplying effect of any error even more). The Office of the Comptroller of the
Currency writes in year 2000: “Computer models are increasingly used in banking to
estimate risk exposure, analyze business strategies and estimate fair values of
financial instruments and acquisitions. As models play an increasingly important
role in decision-making processes, it is critical that bank management reduce the
likelihood of erroneous model output or incorrect interpretation of model results.
The best defense against such "model risk" is the implementation of a sound model
validation framework that includes a robust validation policy and appropriate
independent review.”1.
As we know, since then, this trend has only increased.
The financial instruments being intermediated are ever more complex and so are
the models used to evaluate their value or the risks borne. Moreover, gut-feeling
and expert judgement alone cannot suffice to understand these risks and manage
them objectively and reliably, so, still more models are used to assist the decision
making and management. However, this extensive use of models and complex
models comes with model risk, and as any risk, model risk needs to be managed.
The industry and the regulators first focused on model validation to mitigate this
risk. With time, a deeper understanding as lead to a more comprehensive
approach and set of remedies: Model Risk Management.
In this paper, we give the key points and best practices issued from the published
regulations. Both are relevant and OCC 2011-12 (SR 11-7)2 is building on OCC 2000-
16, we introduced them in chronological order to illustrate the evolution. We also
draw a picture of the state of Model Risk Management in the financial industry
based on our experience and we then present how -we believe- a modern Model
Risk Management framework should be designed today. Finally, we peek into the
future and propose a path to address the remaining frontier: the measurement – or
quantification - of Model Risk.
1 Bulletin OCC 2000-16, now rescinded. It can still be found at: https://www.occ.gov/static/news-issuances/bulletins/rescinded/bulletin-2000-16.pdf 2 Joint publication: Board of Governors - Federal Reserve / OCC: SR 11-7 or OCC 2011-12: https://www.federalreserve.gov/bankinforeg/srletters/sr1107a1.pdf
Model Risk Management. Best Practices for today and tomorrow.
4 OmniMarkets, LLC.
“An effective model
validation process must
address all three
components.”
OCC 2000-16.
1 Regulatory Requirements and Best Practices
Model risk can never be completely eliminated, but in the late 90’s the concept of
model validation started quickly to take hold as a primary means to mitigate model
risk. These efforts were often isolated and uneven, as they did not follow any
industry standards. This all changed with the publication of Bulletin OCC 2000-16
by the Office of the Comptroller of the Currency (“OCC”) on May 30, 2000. About
10 years later, building on the lessons learned, this first landmark bulletin was
replaced in April 2011 by the joint release by the OCC and the Federal Reserve
Board (“FRB”): OCC 2011-12 or SR 11-7. The following seeks to extract the key
points of these 2 bulletins and the best practices for a sound and compliant Model
Risk Management.
1.1 Bulletin OCC 2000-16: a new millennium for Model Risk
Management
The OCC published its landmark bulletin at the start of the new millennium and
changed MRM forever by defining the requirements for model validation and
setting the baseline standard for validation.
1.1.1 Key points of OCC-2000
Definition of the 3 core components of a “model”:
An information input component, which delivers assumptions and data to
the model
A processing component, which contains the theoretical model and
transforms inputs into estimates via computer instructions (i.e. code)
A reporting component, which translates the mathematical estimates into
useful business information
Model Risk Management. Best Practices for today and tomorrow.
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“The personnel performing
model validation should be
as independent as possible
from the personnel who
construct the model.”
OCC 2000-16.
3 generic procedures for Model Validation are defined:
independent review of the logical and conceptual soundness
comparison against other models (Benchmarking)
comparison of model predictions with ‘reality’ (market prices, back-
testing)
OCC 2000-16 put forward Elements of Sound Validation Policy. These
elements emphasize the importance and requirement of independent review.
It also includes a requirement for model documentation “that is sufficiently
detailed to allow the precise replication of the model being described.”
OCC 2000-16 also identified three lines of defense against model risk that had
to be in place:
First Level: Testing performed by model developers. This is the testing
done by developers to check their assumptions, their implementation
and their results to ultimately grow comfortable that their model is
performing as it was intended.
Second Level: independent model validation and testing. Validators
should first review and assess the developers’ documentation and
testing and then also perform additional independent testing.
Third Level: Internal Audit’s review. The Audit’s role is to assess
developers and the validators played their part correctly, i.e. in
accordance with the official policy and procedure documents defining
the firm’s requirements for the 1st and 2nd Level. The policy and
procedures must also be compliant (with OCC 2000-16 / OCC 2011-12).
1.1.2 Sound Model Validation policy OCC 2000-16 mentions that validation policy should help ensure the model-
validation efforts are consistent with senior management’s view regarding the
proper trade-off between costs and benefits. The policy thus includes the following
elements:
Independent Review:
The personnel performing model validation should be as
independent as possible from the personnel constructing the
model
Validation policy should provide for as independent a review as
practicable, and can be complemented by external reviewers or
internal audit
When comprehensive independence is not practicable, the policy
should explicitly provide for an effective communication process
between modelers and decision makers
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Defined responsibilities
The responsibility for model validation should be formalized, and before a
model can enter production the following units should be specified by
senior management:
the independent model-validation unit or external reviewer must
document the model validation tests and the reasons for
concluding that the model is valid
internal audit must verify that no models enter production without
formal approval by the validation unit.
Model documentation
At the organization level, a catalogue of models and their
applications should be maintained.
The most rigorous policies demand documentation detailed to a
level sufficient to allow the precise replication of the model.
Ongoing Validation
Best practices for validation policies require that all changes in the
modeling process be documented and submitted for independent
review.
A useful practice is to allow model changes only periodically, and
only after independent review and approval by the appropriate
level of the bank’s decision makers.
Models should be subjected to change-control procedures, so that
code cannot be altered except by approved parties.
Internal Audit Oversight
1.1.3 Model Validation procedure Below are the key steps of a sound model validation procedure:
Validate the model Input Component:
If the data comes from internal sources, the audit functions need
to ensure it is consistent with other uses (e.g. General Ledger)
If the data originates from external providers, it needs to be
checked against alternative sources.
Models may have dependencies between each other, i.e. some
inputs may be the output of other models (e.g. yield curves or
volatility surfaces)
Validate the model’s underlying assumptions: Assumptions should be
validated with respect to whether it is valid for the model’s intended use.
Model Risk Management. Best Practices for today and tomorrow.
7 OmniMarkets, LLC.
Important behavioral assumptions should be routinely compared to actual
portfolio behaviors.
Validate the model’s quantitative components. A central point of the
model validation is the independent review of the conceptual soundness of
the model. The underlying theory and mathematical methodologies
employed by the developers need to be validated for soundness and
acceptance by others (practitioners, academia . . .). Comparing the model
to well-accepted alternative models (benchmarks) is often useful and may
reveal weaknesses or limitations.
Verify the model’s implementation into production code. OCC/FRB
standards require validators to not just assess the appropriateness of the
model for its intended application, but also to verify that the model is
correctly implemented in production. Well-validated “benchmark” models
are often used for many types of pricing and curve construction
applications, but not generally for risk models. We know of three basic
approaches to verifying implementation of a model:
Line-by-line source code review. This is tedious and error-prone.
This can only be done for simple models with few lines of code.
Benchmarking against alternative similar validated models. This is
often the choice of validators because of speed but it opens the
door to residual differences.
Replication. This is of course the ‘real’ and best way, but a full
replication can be very time-consuming and even more to the point
it presumes a sufficiently detailed documentation.
Validate the model outputs. Validators need to assess how the model
estimates compare with other measurements: either market prices or
estimates from alternative well-accepted models. While this is often
possible for pricing models, risk models often require implementing
alternative models (benchmarks) because of lack of publicly available data.
Model Risk Management. Best Practices for today and tomorrow.
8 OmniMarkets, LLC.
1.2 OCC Bulletin 2011-12 replaces 2000-16 – Key points:
As said, OCC 2011-12 (SR 11-7) builds on the earlier bulletin, adding some
requirements and providing a more comprehensive view of MRM, mirroring a
maturing understanding of MRM by the financial community.
Most noticeably:
• More detail is provided on the model review process and methodology
• It underscores the importance of independent validation, ongoing
monitoring and regular (annual) reviews.
• The role of internal audit is detailed in a new section (see below)
• It requires the validation of vendor and other 3rd party models
• It requires model stress-testing (previously absent)
1.2.1 OCC 2011-12/SR 11-7 - The role of Internal Audit We are quoting from the bulletin verbatim:
“Internal audit also has an important role in ensuring that validation work is
conducted properly and that appropriate effective challenge is being carried out. It
should evaluate the objectivity, competence, and organizational standing of the key
validation participants, with the ultimate goal of ascertaining whether those
participants have the right incentives to discover and report deficiencies. Internal
audit should review validation activities conducted by internal and external parties
with the same rigor to see if those activities are being conducted in accordance with
this guidance. Internal audit should verify that acceptable policies are in place and
that model owners and control groups comply with those policies. Internal audit
should also verify records of model use and validation to test whether validations
are performed in a timely manner and whether models are subject to controls that
appropriately account for any weaknesses in validation activities. Accuracy and
completeness of the model inventory should be assessed.”
Model Risk Management. Best Practices for today and tomorrow.
9 OmniMarkets, LLC.
“One common misconception
is that validation of the
computer processing is not
necessary for vendor models,
because these models have
"met the market test." In fact,
banks that apply good
validation procedures to
vendor models often find
material processing errors.”
OCC 2000-16.
1.2.2 Model Validation – Best practice elements • Element 1: Make sure a model validation policy with clear responsibility
assignments and documentation procedures is in place
• Element 2: Ensure a well-documented model inventory is in place
• Element 3: Validations should be initiated with a request for documentation from
the model developers, and start with checking the document’s
completeness. Inadequate documentation may lead to a rejection of
validation request from senior management.
However, in practice, documentation is often either absent altogether
or incomplete. But rejecting a request for validation is rarely
feasible/practical nor desirable; however, this should be the stated
goal in terms of procedures and policies, in order to slowly change
behaviors and documentation does not remain an afterthought of
development.
• Element 4: The validation document should always cover information provided by
the model developers’ documents. This includes but not limited to the
reasoning for selecting the model, the data and assumptions used by
the model and the testing process of the model.
• Element 5: Stress-testing, as a newly added aspect in OCC 2011-12, should be put
in place to ensure the robustness of the model with various scenarios
• Element 6: Finally, prepare and issue a Model Validation Report that includes:
- An executive summary page with approval/disapproval status
(and limitations/restrictions) of the model clearly indicated.
- A conceptual assessment including an assessment of the
developer’s documentation (including development evidence and
testing), all theory, assumptions, mathematics . . .
- A technical assessment including implementation verification (by
independent replication, code review or benchmarking) and
additional independent testing (including stress testing, reverse
stress testing and back testing).
- A detailed section describing ‘effective challenges’ made by the
validators
- A final conclusion about the models’ appropriateness and
suitability for its intended application.
- A summary of any findings or shortcomings in the model that will
not cause the model to be failed but require remediation.
• Element 7: Prepare for examination. Validator should except the review of their
work by Internal Audit (3rd Level) and by the regulators, so all data,
documents, research documents, code, etc. . . . should be gathered
into a complete package to allow for a full independent review.
Model Risk Management. Best Practices for today and tomorrow.
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2 Model Risk Management today
The regulations above are clear and SR 11-7 (OCC 2011-12) has been out for over
five years and the industry has made great progress towards compliance.
However, as always, changing people’s habits is hard – very hard - and it is slow.
Also, we are noting a big diversity in the progress depending on the size of the
institution (and the budgets/efforts invested) as well as on the various area of the
MRM.
2.1 Model development
The industry and quants have been familiar with model development for a very
long time. There is no real problem on the model development, per se, the only
issue is really the governance of the development and more specifically its
documentation. As the authority of Model Risk Managers increases, and rules &
procedures improve, we should note further progress and the acceptance that no
model development is complete absent a complete documentation.
2.2 Model Validation
Model Validation is another concept that the industry has found relatively easy to
grasp. The real issues here are more the scope (what needs to be validated?) as
well as the depth of the validations. Also, we find most of the focus is often
disproportionately put on the processing component of the models, without paying
sufficient attention both to the input component (calibrations, assumptions,
market data, . . .) as well as on the reporting component and its business usage.
Furthermore, due to incomplete (sometimes absent) documentation validators too
often rely on benchmarks, which are a convenient time-saving approach for the
replication step, but this approach does not bring the full value of an independent
replication (bug correction, documentation improvement, . . .).
2.3 On-going monitoring
This is an area where we find people still have issues understanding the regulation
or at least translating it into actions/procedures, hence this area is often
missing/omitted. “Model Risk on-going monitoring”? What does that mean?
The regulatory guidance provides us with the answer: “On-going monitoring”
means a ‘surveillance’ function to monitor any change in the circumstance of a
particular model, that is any change in the circumstance of any of the 3
components of a model:
Model Risk Management. Best Practices for today and tomorrow.
11 OmniMarkets, LLC.
Tests and checks should be put in place and run on a regular basis (frequency and
change events) to ensure that the reality of the model matches or is within the
bounds of the documented development, validation and audit, once the model is in
use (in production).
Any change in the model circumstance, in turn should trigger a documented
Review & Decision Step. The review may be very quick and the decision may be
that nothing needs to be done; or, on the contrary, the decision may be that a full
validation is warranted. Either way, good governance demands this Review and
Decision Step be made and documented.
2.4 Models Inventory
Following the recommendation of the regulation and drawing up the inventory is
really transformational for an organization. Indeed, it compels the organization to
view model risk, not as a series loosely connected mandatory tasks, procedures or
policies, but it brings everything together, it ‘glues’ everything together and allows
the organization to view model risk in a comprehensive (coverage) and a holistic
manner (actors, processes, tasks, policies).
The simple listing of the models is incredibly informational to an organization,
because it forces it to define the scope (what should be included?) as well as look
for long forgotten used models.
This simple piece of information will reveal a real map of where the organization
and a road map for management of what remains to be done. Immediate insights
will be available: how many models? How many external/internal? Can we
streamline our data and avoid redundancies or dangerous independent duplicates?
Overall, by bringing the first comprehensive view, the inventory of models used is
very transformational because the information it will reveal will undoubtedly
provide the impetus for change and improvement.
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12 OmniMarkets, LLC.
3 Raising the bar: “M” is for Management
The regulations pre-cited are clear and the implementation of the best practices is
a great step forward in order to mitigate Model Risk; however, they do not help the
risk manager actually manage this risk and the additional amount of tasks and work
they demand. The inventory is a very necessary step for MRM but it is not
sufficient for real management of the model risk.
Two additional layers are needed to help the risk manager with his daily
surveillance and management function: (1) a summary dashboard of the inventory
and (2) processes and procedures, to link all the different pieces of MRM
(development, implementation, validation, on-going monitoring, inventory)
together as well as with the set of tasks/actions that need to be completed in
relation to a change in the circumstance of any model.
Such a framework allows a horizontal (and aggregate) view of all the models, but it
can also be improved to allow for a vertical view across all the models and
businesses.
3.1 Holistic MRM
As previously noted, the various tasks of MRM are clearly defined and an inventory
of all the models is an essential part of modern MRM. However, to be really useful
and helpful to the risk manager, a higher level of information needs to be designed
for each MRM task allowing for global view, in a clear and simple dashboard:
summary information relating to the MRM element as well as an overall grade for
the element considered (development, implementation, validation . . .).
This summary information – MRM level information - needs to be designed
following the guidelines but, more importantly, following the specific
circumstances of the organization and in relation to its goals from an MRM level.
From experience, using something simple like traffic lights of grading from 1 to 5 is
the better way to go.
See next page for a graphical illustration (only 2 models).
Model Risk Management. Best Practices for today and tomorrow.
13 OmniMarkets, LLC.
Once in place, such MRM level information for all the elements brings new and
higher level information to the risk manager. For example, if traffic lights grading
was used, a dashboard can simply be designed to show:
- How many elements of MRM are in the Green? Yellow? Red?
- Inventory of models broken down along various axis: internal/external or
category of models (valuation, risk, liquidity, revenues, capital . . .)
- How many model validations need to be completed in the next month?
Quarter? Year?
- How many documentations are missing?
This view would of course provide great insights to the risk manager, the internal
audit and facilitate the reporting to the upper management.
General Information - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Development- - - - - - - - - - - - - - - -
Implementation- - - - - - - - - - - - - - - -
Validation- - - - - - - - - - - - - - - -
On-going monitoring- - - - - - - - - - - - - - - -
Internal Audit- - - - - - - - - - - - - - - -
General Information - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Development- - - - - - - - - - - - - - - -
Implementation- - - - - - - - - - - - - - - -
Validation- - - - - - - - - - - - - - - -
On-going monitoring- - - - - - - - - - - - - - - -
Internal Audit- - - - - - - - - - - - - - - -
Model #1
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Model #2
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Documents, Reports, Code, Data, . . .
Inventory
Summary information
and Scorecard
Full work products
package of MRM elements
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14 OmniMarkets, LLC.
3.2 Governance = workflows
Once the MRM framework described above is in place, simple workflows can be
put in place alongside alerts to transform the MRM framework into a real MRM
system/application. For example, an alert is being raised because the Point of
Contact (“POC”) for its Model Development task has left the organization and a
new POC needs to be designated and given that responsibility. Or the
automatically run tests & checks show a breach (data moved out of bounds) for
one of the levels of underlying assumptions; or the market has moved significantly
from the last calibration etc.
Naturally the action(s) that result from each event/alert need to be designed to be
fully adapted to the organization. Workflows basically translate the governance
around MRM into code.
3.3 Interactions between models
If the information at the MRM level is designed correctly, the inventory designed
above will also allow for the visualization of the interactions between models. For
example, the estimates generated by model X are used downstream for the input
of model Y (assumptions, calibration, prices . . .). This can potentially reveal hidden
or overlooked issues and, more importantly, it is essential information for the
validation and the on-going monitoring of model Y.
From these interactions, graphs of downstream dependencies originating from the
external data sources can be drawn (it would look like trees) and underscore their
respective importance or lack thereof. Once an organization finds that a single and
questionable data source is at the origin of multiple key estimates; the organization
may want to invest in this particular data, to multiply the sources or at least check
it more closely.
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Similarly, upstream paths illustrating all the upstream dependencies of a particular
model will be able to be drawn:
As we have seen, true Management of Model Risk goes beyond following the best
practices of the various elements of MRM: development, implementation,
validation, on-going monitoring, inventory. It requires an additional layer of
indicators and processes to articulate the basic elements and allow for real
management. From our experience, this piece is often still missing and only the
major global banks have invested and made the effort to put such framework in
place. That being said, as the FRB raises the bar constantly, there is no doubt in our
minds that such MRM frameworks will become more widely implemented.
The final frontier for MRM is its quantification. After all, model risk is risk and, as
such, it should be measured (not just managed) and capital should be put aside to
account for its measure. Ideally its measure could be aggregated with the
measures of other types of risks. The industry is not there yet, but in the following
chapter we offer a potential path towards such measurement.
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4 Quantifying Model Risk
MRM is Risk and as such in the end, the industry will need to start quantifying it
and account for it. In the end, what we ought to have is a measure that can be
integrated in the overall measure of risks a financial institution faces. How can this
be done practically today? What direction are we embarking on towards this goal?
4.1 Measurement of MRM – 1st Generation: KPI
As was done for operational risk, one approach to start quantifying Model Risk
would be to associate each MRM elements and sub-elements to Key Performance
Indicators (KPI’s). Here too, we think the best way to go is to keep things simple
with either traffic lights or 1 to 5 grading.
Depending on how it was designed, this most likely will require an increase in the
number of data points on the summary information (report card) for each element.
However, once in place, aggregations/statistics can then be made at different levels
and along different axis, to measure and analyze the model risk from various
angles. This would give an organization a first measurement and also an easy way
to track progress.
This first measurement could be improved by taking into account (weights) the
importance of the model being gauged: its materiality. Additional information (e.g.
complexity or uncertainties) can easily be added by simple questionnaire.
4.2 Measurement of MRM – 2nd Generation: PE, EAE and LGE
Again, taking as a model what has been done on the operational risk, one can
envision that before long banks and other financial institutions will anonymously
submit model risk incidents or errors. Naturally, the willingness of the industry to
share information about errors made remains to be seen, but this is a clear path
towards the quantification of Model Risk.
Once this data is available, the industry will undoubtedly model the Expected Loss
due to Model Risk in the a very familiar way:
𝐸𝐿 = 𝑃𝐸 × 𝐸𝐴𝐸 × 𝐿𝐺𝐸
EL: Expected Loss due to Model Risk error/incident
EAE: Exposure At Error (or incident). Basically the materiality of the model relating
to the error/incident.
LGE: Loss Given Error
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With the adequate standardized data available3, given a certain state of its own
MRM, an organization will be able to easily infer the various values of the
equations above.
3 A similar endeavor was started for the sake of Operational Risk years ago by www.ORX.org and we expect the industry under the pressure of the regulators to launch a similar effort.
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References
1. “Concepts to Validate Valuation Models”, P. Whitehead, in: “Risk Model
Evaluation Handbook”, G. Gregoriou, C. Hoppe and C. Wehn (Eds), 2010
2. “Understanding and Managing Model Risk”, Morini 2011
3. “Model Validation: theory, practice and perspectives”, Henaff 2012
Model Risk Management. Best Practices for today and tomorrow.
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OmniMarkets – Senior Team
Mr. Pierre Leignadier
Mr. Leignadier-Fahlström launched OmniMarkets in 2004. Prior to OmniMarkets,
he was the head of Scandinavian interest-rate derivatives trading at Svenska
Handelsbanken in London. He also headed the Securitized Credit Analytics team at
Calyon Americas. He was a derivatives trader and quantitative developer for
Banque Indosuez in Paris and Stockholm.
Mr. Leignadier-Fahlström has a Master of Philosophy in Quantitative Finance from
Ecole Normale Superieure de Cachan (France) and a Master in Biology and
Mathematics from Agro Paris-Tech, Institute National Agronomique Paris-Grignon
(France). His expertise includes trading, portfolio and risk management and
structured finance.
Mr. Yihui (Kevin) Zhang
Mr. Zhang is a Managing Director at OmniMarkets specializing in structured finance
and quantitative research and development. Prior to joining OmniMarkets, Mr.
Zhang was a statistical researcher at the Centre for Economic Development
Research in China and an equity analyst at CITIC Securities in Wuhan, China.
Mr. Zhang holds a MS in Economics from Wuhan University and a MS in Financial
Engineering from Claremont Graduate University, CA (USA). He also received a BS in
Automotive Engineering & Economics from Wuhan University of Technology, Mr.
Zhang’s expertise includes macro-economy, quantitative finance and statistical
analysis.
Mr. Robert Tian
Mr. Tian is OmniMarkets' Model Risk Management (MRM) Advisor. He is currently
the director of risk modeling at a regional bank in New England, managing a team
of quants to develop all credit risk models to support operation, reporting and
compliance purposes. Previously, he was a senior manager of MRM at GE Capital,
and a senior analyst of MRM at Freddie Mac Internal Audit.
Mr. Tian holds a PhD in Econometrics from SUNY at Albany (NY, US) and a Master in
Statistics from Tsinghua University (China). Mr. Tian has deep experience in
modeling, model risk management and regulatory communication.
Mr. Sasha Stoikov
Mr. Stoikov is OmniMarkets’ Quantitative Finance Advisor. He is currently the Head
of Research at Cornell Financial Engineering Manhattan (CFEM, New York, US), a
satellite campus of Cornell University. Previously, he was a Senior Vice President of
High Frequency Trading at Cantor Fitzgerald (New York, US).
Mr. Stoikov holds a PhD in Mathematics from The University of Texas at Austin, and
a BS in Mathematics from Massachusetts Institute of Technology (MIT). His
expertise includes order book dynamics, high frequency trading, quantitative
finance, applied mathematics, mathematical and statistical modeling.