Financial institutions can leverage machine learning to make an array of functions faster, more accurate and more efficient. But deployment is just the first step. In the end, machine learning governance makes or breaks the efficacy of any system.
In today’s banking and financial services world, we are rebuilding many finance, risk, actuary, forecasting and macroeconomic models using Python, R and other open-source programming languages. Increasingly, we incorporate machine learning (ML) algorithms into these functions so that a traditional deterministic model becomes a self-learning and self-tuning program, aided by supervised, unsupervised or reinforced learning methods.
Such emerging technologies mostly lack explicit pre-programmed routines. They feed on a diverse spectrum of datasets, and they evolve continuously by learning from past examples and experience. Naturally, these ML models can’t simply be left alone to derive insights on their own for any period of time. They demand constant revision to account for model control, audit and regulatory compliance requirements.
As more and more rule-based or deterministic models (statistical, financial or quantitative models) adopt ML capabilities, we must build controls in such a way that the model’s objectives, construct, data need, desired performance level and trustworthiness can be measured and appropriately managed in alignment with the company’s risk appetite. Moreover, in an autonomous model management framework, we expect to see early warning indicators or alerts whenever a threshold is breached under any of the aforementioned areas.
However, none of these governance initiatives should diminish the pace of AI uptake, innovation and research excellence in model governance. This article covers some key principles underpinning the target machine learning governance framework and some essential components.
Core Principles of Machine Learning Governance
Principle 1: Be Transparent
Transparency has a threefold connotation. First, in an end-user interaction, it is often critical to disclose that the other party or usable system is a machine learning model and not a regular program or a human agent. Second, it involves understanding how a typical ML model is developed, trained, deployed and operated. This understanding could be either from a developer’s standpoint or from an end user’s standpoint. Third, developers should raise general awareness about standard ML algorithms and how they are leveraged for typical financial use cases, such as fair lending, credit decisioning, anomaly detection, customer onboarding, stock price forecasting, fraud management, underwriting and so on.
Principle 2: Be Predictable
This generally refers to understanding the various factors (e.g., data, logic, algorithms) behind a certain autonomous decision and their correlation with the outcome. In doing so, one must be careful not to compromise data privacy boundaries. The understanding should be clear enough for the end users so that in case of a valid dispute, they can challenge the outcome.
Principle 3: Reduce Bias
A key objective of an ML model framework should be to lower societal bias as much as possible. No system should impede the fundamental rights or financial inclusion of the end user. An algorithm that is opaque and makes questionable or discriminatory decisions on the basis of sensitive parameters such as race, ethnicity, religion, national origin or age can immediately elicit deeper scrutiny and penalties. Take, for example, the Equal Credit Opportunity Act (ECOA), which mandates that creditors notify applicants about the principal reasons of a credit decline. An ML-based fair lending model must be self-explanatory to generate a commentary against any decline, and the reason should not be a societal bias embedded into the model due to a poor choice of training data.
Principle 4: Be Fair and Ethical
If ML models promote more human-centric values such as fairness, equality and justice, then it wins more public trust and, therefore, the potential for faster adoption.
The adoption of ML models should not have negative human rights implications due to the denial of social rights. The same goes for any labor market transitions due to manual jobs being replaced by robots. This is where an ethical risk assessment becomes critical.
Unfair, deceptive or abusive acts or practices (UDAAP) under the Dodd-Frank Act serves as a huge guardrail against any potential unethical judgment made by ML models.
Principle 5: Be Accountable
Accountability lays out responsibility on specific stakeholders who are responsible for developing, deploying and maintaining ML models. The stakeholders could be the end-user organization or a third-party firm. However, they should be legally liable for any consequences due to the decisions taken by the models. Moreover, accountability also means that the identified stakeholders should be fully aware of the decision logic and should be able to explain any outcome caused by the models. This attempts to minimize the possibility of any algorithmic harm caused by the system due to the breach of any social norm, legal guideline or human expectation.
Model Governance Reimagined: Some Components
Banks and fintech firms are busy redesigning their existing model management architecture to introduce new components to help realize some or all of these principles. Many of these components essentially help to remediate the typical challenges that ML models bring in, such as opacity, complexity, algorithmic bias, etc.
Let us look at few examples.
A Model Registry
A model registry is a centralized repository and platform for collaboratively building, managing, training, deploying and providing comprehensive annotations for ML model artifacts. A successful model registry system increases transparency and results in fewer handoffs between the dev team and release engineers. Since model registry is the new-age model version control and life cycle management system enabling one-click deployment or integration of the model, it is a critical tool for model auditors, model validators and release/integration engineers.
Open-source platforms such as MLFlow offer a comprehensive model registry platform that can be used across multiple first- and second-line model risk teams.
A collaborative model registry system attempts to enhance transparency and predictability by making the model development life cycle more collaborative and understandable by clear lineage documentation.
Model Data Control
When an ML model goes awry, the training dataset is to blame in most cases. It is critical to ensure that the training data is neither preferentially sampled, nor reflecting an existing societal bias. Both can be detected early and fixed by tweaking the data preprocessing techniques. An example could be when our credit application dataset is collected from a very narrow social segment, with the model showing only working males of a specific age group as having been granted loans. This may wrongly train the algorithm to not consider nonworking female candidates as creditworthy candidates.
Even after the ML model is deployed, it is possible that the supervised model is overwhelmed by a wide variety of unseen data with an unknown pattern. Some of the premeditated data poisoning attacks also fall in this category. The result is simple: Model integrity is lost, and it comes up with outrageous decisions.
Additionally, data privacy must not be compromised. We must ensure that sensitive parameters critical for an accurate model forecast are used for building the model.
Data remediation is not simple; extensive training for datasets and rigorous validation processes are recommended. Periodic monitoring of operational model outcome helps to assess model decay and detect adversarial attacks.
An Independent Model Audit
Involving a human in independent model oversight and understanding logic and data is a significant control and a chief asset to any ML governance practice. This can ensure that complete model autonomy does not break the system or make unpredictable decisions with negative consequences. Another benefit of bringing a human into the equation is ensuring that the typical human-centered values, fundamental rights or democratic values are not endangered by the ML models. Consider an AI-powered customer onboarding system: The ML model responsible for performing digital due diligence on and onboarding new customers may reject an application due to a discriminatory profiling logic. A human layer of model outcome validation may help to fix such wrongful decisions.
A European Approach to Excellence in AI
The European Commission has recently proposed a legal framework toward achieving trustworthy artificial intelligence, the essence of which is a risk-based approach for classifying and remediating AI-based systems. Regulatory authorities are encouraging usage of regulatory sandboxes for controlled testing and validation of ML models before they are operationalized. This helps to identify bigger systemic risks (e.g., an ML model that ignores genuine fraudulent transactions as nonsuspicious) at the pre-marketing phase.
An Ethical Risk Assessment Framework
It is possible that human prejudices or historical societal biases get perpetuated into ML models as well because the models are trained using historical real data and human engineers are training those. It is also possible that due to imbalanced or underrepresented datasets, the ML model overlooks a certain segment during its training process.
All these risks have potential impact on human rights, including equality, liberty and privacy. An online campaign management system driven by ML models may target a specific racial group for a financial product due to its training data. This outcome is discriminatory on prohibited biases, and hence, not ethical by certain standards.
A thorough ethical risk assessment is needed for the various ML models impacting processes including new customer onboarding, online loan approval, cross-selling or upselling a financial product, credit scoring and so on. This assessment is not only to detect algorithmic bias, but also to take note of any proxy or parameters used by the model that can be considered sensitive. Unethical behavior by ML models could be a massive source of misconduct risk and subsequent litigation. This is important.
Conclusion
With the advent of more innovation in the ML models, we will expect to see extremely sophisticated tools and techniques in this space in the future. Therefore, the machine learning governance framework must equally evolve to manage all the societal, legal and reputational implications brought in by this new wave of intelligent models.
Sanjukta Dhar leads the market and treasury risk management portfolio within the BFSI CRO Strategic Initiative of Tata Consultancy Services (TCS). Dhar has played the role of a business analyst, solution architect, SME and implementation lead across multiple financial risk management system implementations for major banks and financial services.
