Releasing a Machine Learning (ML) model into the wild does not mark the end of an AI project, contrary to a widespread misconception among companies venturing into AI. In reality, it's the exact opposite - ML initiatives call for constant attention even after deployment, primarily from your top-notch engineers and researchers.
The Need for Constant Model Upkeep
If you've developed and utilized a model extensively, it's evident that its performance progressively deteriorates. To retain the initial precision and circumvent this degradation, it's imperative to maintain a regular update schedule and monitor the model frequently. With every fresh influx of data, it's best if algorithms are updated. This upkeep demand isn't automated, requiring a meticulous review, analytical thinking, and manual efforts that only highly skilled data scientists can offer.
Comparing ML Solutions to Traditional Software
Operating ML solutions thus has higher incremental costs than traditional software solutions, while the intent of deploying these is to cut down expenses related to human labor.
Understanding Model Degradation
Why degradation occurs? As soon as the models leave the training stage, their accuracy is often at the peak. Making accurate predictions using a model built on suitable and available data is a strong start but the question is, for how long do you expect the now aging data to continue making accurate forecasts? The latent performance of the model is bound to decline daily – a phenomenon known as concept drift. It's well studied in academia but less addressed in the commercial realm. When the statistical characteristics of the target variable your model is trying to predict, alter unpredictably over time, concept drift happens.
Implications of Concept Drift
In simple terms, your model isn’t aptly modeling the outcome it previously did, leading to ML model degradation, a fault commonly observed in human behavior models. The fundamental distinction between an ML model and a basic calculator is interaction with the real world. Consequently, data produced and acquired changes over time and forecasting this data evolution should be integral to any ML study.
Detecting and Addressing Degradation
Identifying degradation: Observe your ML systems closely, as they're more fragile than anticipated. Should you notice model degradation, revamping your model pipeline is the answer. One such detection method is manual learning. Here, we run new accumulative data through our system, repeating the same training and deployment procedure as when it was initially built. This time-consuming process is not mainly about updating and retraining, but identifying new features to resist concept drift.
Furthermore, scale your data. Certain algorithms make it easy, while others necessitate a custom-built approach. One possible strategy is to inverse proportional age weighting, assigning greater weight to the most recent data and lesser to the oldest data in your training dataset. This allows your system to spot any potential drifts and make necessary adjustments.
Implementing Always-On Production Systems
The most effective solution is designing an always-on production system for repeated evaluation and retraining of your models. An advantage of such continual learning system is its high levels of automation, thereby reducing human labor costs.
The Consequences of Ignoring Concept Drift
ML models in production function differently from their training phase due to concept drift. This issue could lead to subpar user experiences or even model failure if not adequately anticipated. Monitoring your data and early drift detection is crucial when your data evolves over time. Tactics such as frequent retraining or ensemble methods can help prevent drifts initially.
Tackle machine learning drift before it starts affecting your product. If left unaddressed, it leads to a sharp dip in trust and formidable repair costs. Always be proactive!