Overview: Model Retraining
Model retraining is updating a machine learning model with new data or refining its parameters to ensure that it remains accurate and effective over time. Equity-aware practices must drive this process.
Bias Detection Monitoring in New Data Sets and Features
Monitoring bias detection in new datasets or features is essential for maintaining fairness and transparency in AI systems. The steps outlined below serve as a useful framework for monitoring bias detection:1
- Identify key metrics to quantify bias in the dataset, such as demographic parity, equal opportunity, or disparate impact.
- Implement automated processes to continuously monitor bias metrics in new datasets or features.
- Integrate bias detection into the data pipeline, ensuring that it occurs as part of routine data processing.
- Analyze the importance of new features in the model's predictions and assess their potential impact on bias.
- Identify features that may correlate with sensitive attributes and require closer scrutiny.
- Continuously evaluate the performance of AI models on new datasets, paying attention to fairness metrics across different demographic groups.
- Compare model performance on historical and new data to detect discrepancies or biases.
- Incorporate human reviewers or ethicists to assess potential biases in new datasets or features.
Bias detection is an ongoing process, and applying a systematized approach ensures AI systems' fairness and transparency.
Model Versioning
Comparing models with prior versions, implementing versioning, enabling rollback mechanisms, and incorporating incremental training facilitate the management of changes and updates, ensure reproducibility, and allow for adaptation to evolving data and requirements. The following scheme can guide developers in integrating these aspects into their workflow:2
Model Comparison with Prior Versions: Continuously track performance metrics (e.g., accuracy, precision, recall) for each model version. Compare the performance of new models with previous versions to assess improvements or regressions.
Versioning:
- Unique Identifiers: Assign unique identifiers to each model version to facilitate tracking and management.
- Version Control Systems: Utilize version control systems (e.g., Git) to manage changes to model code, configurations, and data preprocessing steps.
- Model Metadata: Store metadata for each model version, including training data, hyperparameters, and evaluation results.
Rollback Mechanisms:
- Automated Rollback: Implement automated rollback mechanisms triggered by performance degradation or validation failures. Rollback to the previous stable version to ensure uninterrupted service and mitigate risks associated with model regressions.
- Manual Intervention: Provide the option for manual intervention to initiate rollbacks based on human judgment or specific criteria.
Incremental Training:
- Data Accumulation: Accumulate new data continuously or periodically to update models with the latest information. Retraining Strategies: Develop strategies for incremental training, such as online learning or mini-batch updates, to incorporate new data while minimizing computational resources.
- Transfer Learning: Leverage transfer learning techniques to efficiently adapt pre-trained models to new data domains or tasks.
A/B Testing and Experimentation: Conduct A/B tests to compare the performance of new model versions against baseline or existing models. Use experimentation frameworks to systematically evaluate changes and iterate on model improvements.3
Automated Pipelines: Set up Continuous Integration and Deployment (CI/CD) pipelines to automate model training, testing, and deployment processes. Ensure that each code commit triggers automated tests and validation checks before deployment.
Monitoring and Alerting:
- Performance Monitoring: Continuously monitor model performance in production, including latency, throughput, and accuracy.
- Anomaly Detection: Implement anomaly detection mechanisms to detect deviations from expected behavior and trigger alerts for potential issues.
Documentation and Communication:
- Change Logs: Maintain detailed change logs documenting modifications made to each model version.
- Communication Channels: Establish communication channels for notifying stakeholders about model updates, rollbacks, and performance changes.
Stakeholder Involvement: Involve diverse stakeholders, including data scientists, engineers, product managers, and business analysts, in the model management process. Foster collaboration and knowledge sharing to ensure alignment with business goals and user needs.
Developers wishing to dive deeper into the technical aspects of ensuring equity in AI can access our GitHub site.
Reference this resource we created, Model Retraining Guiding Questions, to support your discussion at this phase.
- McKenna, M. (n.d.). Bias in AI: How to Mitigate Bias in AI Systems. Toptal. toptal.com
- Henry, J. (2023). Model Rollbacks Through Versioning. Towards Data Science. towardsdatascience.com
- Patel, H. (n.d.). How to A/B Test ML Models?. Censius. censius.ai
Overview: Model Retraining
Model retraining is updating a machine learning model with new data or refining its parameters to ensure that it remains accurate and effective over time. Equity-aware practices must drive this process.