Why drift in machine learning can deteriorate your model’s performance—and what you can do about it
Why drift in machine learning can deteriorate your model’s performance—and what you can do about it



Machine learning models are powerful tools that help organizations make smarter decisions. However, over time, a model’s performance can drop as the data it was trained on no longer reflects current conditions. This phenomenon is known as drift. In this post, we explain drift in machine learning, explore the different types, and discuss how decision makers can take simple steps to maintain model performance—even if they are not data science experts.
Machine learning models are powerful tools that help organizations make smarter decisions. However, over time, a model’s performance can drop as the data it was trained on no longer reflects current conditions. This phenomenon is known as drift. In this post, we explain drift in machine learning, explore the different types, and discuss how decision makers can take simple steps to maintain model performance—even if they are not data science experts.
Machine learning models are powerful tools that help organizations make smarter decisions. However, over time, a model’s performance can drop as the data it was trained on no longer reflects current conditions. This phenomenon is known as drift. In this post, we explain drift in machine learning, explore the different types, and discuss how decision makers can take simple steps to maintain model performance—even if they are not data science experts.
What is drift in machine learning?
Drift in machine learning occurs when a model that once made accurate predictions begins to perform poorly. It doesn’t refer to cars drifting on a racetrack; rather, it describes a change over time in the data environment that makes the original model less effective. Drift happens when the characteristics of the input data change or when the relationship between the data and the target outcome shifts.
Think of it like this: Imagine you built a model based on last year’s customer data. If your customer demographics or buying behavior change this year, the model might not predict trends as accurately. This decline in performance is drift at work.

Drift can show up in several ways. It may occur suddenly, as when a new data collection method is introduced, or it might happen gradually as the underlying patterns slowly evolve. Sometimes, drift follows a recurring pattern, such as seasonal changes. Recognizing drift early helps prevent significant drops in performance.
The four types of drift
Understanding the specific type of drift that affects your model is key to choosing the right countermeasure. In our discussion, we focus on four types: feature drift, label drift, prediction drift, and concept drift.
1. Feature drift
Feature drift refers to changes in the input variables your model relies on. For example, imagine your original training data had mostly female subjects. Over time, if your incoming data shifts to predominantly male subjects, the distribution of your features changes. This shift may cause your model to misinterpret the data, ultimately lowering its accuracy.
2. Label drift
Label drift occurs when the distribution of the outcomes or labels changes. Consider a model that flags spam emails. If the percentage of spam emails increases from 1% to 10%, a model that was trained on data with a lower rate might start missing important signals. In this case, the labels (spam versus not spam) have shifted, and the model needs to be updated.
3. Prediction drift
Prediction drift happens when the model’s own outputs begin to show unexpected trends. This type of drift might occur due to a change in how data is interpreted by the model. For instance, if a model that once predicted a 5% chance of an event starts predicting 10% or 15% without a corresponding change in the input data, prediction drift is likely at work.
4. Concept drift
Concept drift is when the underlying relationship between the input data and the outcome changes. This drift is often the result of external factors. For instance, during an economic downturn, the factors that determine credit card defaults may shift dramatically. Even if the data features remain constant, the model’s predictions may suffer because the concept itself has evolved.

Databricks Demo on YouTube : https://youtu.be/tGckE83S-4s?si=uPUrJ86GayUkI-p4&t=470
By breaking down drift into these four types, you can pinpoint which part of your data environment has changed. Each type of drift requires a slightly different approach to address it.
How to detect and prevent drift
Once you understand what drift is and the ways it can manifest, the next step is detecting it and taking action. The most common strategy is to retrain your model using new data that reflects current conditions. However, knowing when to retrain is critical to avoid unnecessary costs or missed opportunities.
Monitoring your data
You can monitor drift by tracking key metrics that reveal changes in data distribution. For instance, by checking average values, medians, or even the spread of your data, you can see if the input variables begin to stray from their historical patterns. Statistical tests, such as the Kolmogorov-Smirnov test or Jensen-Shannon divergence, can also help quantify these changes.
Tracking model performance
Another method involves keeping an eye on the model’s performance metrics. Metrics like accuracy, the area under the curve (AUC), and root mean square error (RMSE) are reliable indicators of how well your model is doing. If you notice that these metrics decline consistently, it might be time to retrain your model.

Databricks Demo on YouTube: https://youtu.be/tGckE83S-4s?si=0Nhky3lK7WJae2n0&t=654
Using tools for drift detection
Modern tools make drift detection more straightforward. One such tool is Evidently AI, an open-source platform that offers preset evaluations to generate comprehensive drift reports. Evidently AI can produce interactive HTML reports that highlight drift across different aspects of your data, such as feature distributions and performance metrics.
Even better, the tool provides structured outputs. This means you can integrate the results into your workflow. When drift reaches a certain threshold, you might automatically trigger model retraining. This process helps ensure your models remain accurate over time without constant manual oversight.
Best practices for handling drift
Set Clear Thresholds: Decide on the performance metrics that matter most to your business. Set thresholds that trigger a review or retraining process when these metrics drop.
Automate Monitoring: Whenever possible, automate the data and performance monitoring process. Automated alerts can help you react quickly before the drift causes serious issues.
Retrain When Necessary: The rule of thumb is to retrain your model “when you need to.” Some environments change slowly and may require annual retraining. In fast-paced settings, retraining might be needed more frequently.
Use Visual Reports: Visual dashboards and interactive reports make it easier for decision makers to understand the data. They provide a clear picture of when drift occurs, allowing you to take timely action.
Bringing it all together
Drift in machine learning poses a real challenge, but it does not have to be a roadblock. By understanding the types of drift and monitoring key indicators, you can keep your models performing at their best. Whether you choose to monitor manually or set up an automated process, the key is to remain proactive and responsive.
For decision makers, this means investing in the right tools and strategies today can save considerable time and resources tomorrow. For data scientists, it emphasizes the importance of a proactive approach to model management. It’s not about if your model will drift, but when. You must be ready to diagnose and refresh when needed as to minimize downtime, mistakes & costs.

Next steps
If you believe your organization could benefit from enhanced drift monitoring, consider scheduling a phone call with our team. We can help you review your current model management practices and identify opportunities for improvement. A simple discussion can lead to significant gains in model performance and business outcomes.
Key Takeaways
Drift in machine learning refers to a decline in model performance over time due to changes in data or underlying relationships.
Four types of drift—feature, label, prediction, and concept drift—affect models in different ways.
Early detection is crucial. Monitor both your data and performance metrics to catch drift before it impacts your business.
Tools like Evidently AI help generate comprehensive reports and enable automated retraining when performance drops.
The mantra is simple: Retrain only when necessary to balance performance improvements with cost considerations.
By keeping these principles in mind, organizations can maintain robust machine learning models that adapt to changing data environments. This proactive approach not only improves model accuracy but also supports long-term strategic planning.
If you have questions or want to explore drift management strategies further, feel free to reach out and schedule a phone call with our experts. We’re here to help you navigate the challenges of maintaining high-performing machine learning models.
What is drift in machine learning?
Drift in machine learning occurs when a model that once made accurate predictions begins to perform poorly. It doesn’t refer to cars drifting on a racetrack; rather, it describes a change over time in the data environment that makes the original model less effective. Drift happens when the characteristics of the input data change or when the relationship between the data and the target outcome shifts.
Think of it like this: Imagine you built a model based on last year’s customer data. If your customer demographics or buying behavior change this year, the model might not predict trends as accurately. This decline in performance is drift at work.

Drift can show up in several ways. It may occur suddenly, as when a new data collection method is introduced, or it might happen gradually as the underlying patterns slowly evolve. Sometimes, drift follows a recurring pattern, such as seasonal changes. Recognizing drift early helps prevent significant drops in performance.
The four types of drift
Understanding the specific type of drift that affects your model is key to choosing the right countermeasure. In our discussion, we focus on four types: feature drift, label drift, prediction drift, and concept drift.
1. Feature drift
Feature drift refers to changes in the input variables your model relies on. For example, imagine your original training data had mostly female subjects. Over time, if your incoming data shifts to predominantly male subjects, the distribution of your features changes. This shift may cause your model to misinterpret the data, ultimately lowering its accuracy.
2. Label drift
Label drift occurs when the distribution of the outcomes or labels changes. Consider a model that flags spam emails. If the percentage of spam emails increases from 1% to 10%, a model that was trained on data with a lower rate might start missing important signals. In this case, the labels (spam versus not spam) have shifted, and the model needs to be updated.
3. Prediction drift
Prediction drift happens when the model’s own outputs begin to show unexpected trends. This type of drift might occur due to a change in how data is interpreted by the model. For instance, if a model that once predicted a 5% chance of an event starts predicting 10% or 15% without a corresponding change in the input data, prediction drift is likely at work.
4. Concept drift
Concept drift is when the underlying relationship between the input data and the outcome changes. This drift is often the result of external factors. For instance, during an economic downturn, the factors that determine credit card defaults may shift dramatically. Even if the data features remain constant, the model’s predictions may suffer because the concept itself has evolved.

Databricks Demo on YouTube : https://youtu.be/tGckE83S-4s?si=uPUrJ86GayUkI-p4&t=470
By breaking down drift into these four types, you can pinpoint which part of your data environment has changed. Each type of drift requires a slightly different approach to address it.
How to detect and prevent drift
Once you understand what drift is and the ways it can manifest, the next step is detecting it and taking action. The most common strategy is to retrain your model using new data that reflects current conditions. However, knowing when to retrain is critical to avoid unnecessary costs or missed opportunities.
Monitoring your data
You can monitor drift by tracking key metrics that reveal changes in data distribution. For instance, by checking average values, medians, or even the spread of your data, you can see if the input variables begin to stray from their historical patterns. Statistical tests, such as the Kolmogorov-Smirnov test or Jensen-Shannon divergence, can also help quantify these changes.
Tracking model performance
Another method involves keeping an eye on the model’s performance metrics. Metrics like accuracy, the area under the curve (AUC), and root mean square error (RMSE) are reliable indicators of how well your model is doing. If you notice that these metrics decline consistently, it might be time to retrain your model.

Databricks Demo on YouTube: https://youtu.be/tGckE83S-4s?si=0Nhky3lK7WJae2n0&t=654
Using tools for drift detection
Modern tools make drift detection more straightforward. One such tool is Evidently AI, an open-source platform that offers preset evaluations to generate comprehensive drift reports. Evidently AI can produce interactive HTML reports that highlight drift across different aspects of your data, such as feature distributions and performance metrics.
Even better, the tool provides structured outputs. This means you can integrate the results into your workflow. When drift reaches a certain threshold, you might automatically trigger model retraining. This process helps ensure your models remain accurate over time without constant manual oversight.
Best practices for handling drift
Set Clear Thresholds: Decide on the performance metrics that matter most to your business. Set thresholds that trigger a review or retraining process when these metrics drop.
Automate Monitoring: Whenever possible, automate the data and performance monitoring process. Automated alerts can help you react quickly before the drift causes serious issues.
Retrain When Necessary: The rule of thumb is to retrain your model “when you need to.” Some environments change slowly and may require annual retraining. In fast-paced settings, retraining might be needed more frequently.
Use Visual Reports: Visual dashboards and interactive reports make it easier for decision makers to understand the data. They provide a clear picture of when drift occurs, allowing you to take timely action.
Bringing it all together
Drift in machine learning poses a real challenge, but it does not have to be a roadblock. By understanding the types of drift and monitoring key indicators, you can keep your models performing at their best. Whether you choose to monitor manually or set up an automated process, the key is to remain proactive and responsive.
For decision makers, this means investing in the right tools and strategies today can save considerable time and resources tomorrow. For data scientists, it emphasizes the importance of a proactive approach to model management. It’s not about if your model will drift, but when. You must be ready to diagnose and refresh when needed as to minimize downtime, mistakes & costs.

Next steps
If you believe your organization could benefit from enhanced drift monitoring, consider scheduling a phone call with our team. We can help you review your current model management practices and identify opportunities for improvement. A simple discussion can lead to significant gains in model performance and business outcomes.
Key Takeaways
Drift in machine learning refers to a decline in model performance over time due to changes in data or underlying relationships.
Four types of drift—feature, label, prediction, and concept drift—affect models in different ways.
Early detection is crucial. Monitor both your data and performance metrics to catch drift before it impacts your business.
Tools like Evidently AI help generate comprehensive reports and enable automated retraining when performance drops.
The mantra is simple: Retrain only when necessary to balance performance improvements with cost considerations.
By keeping these principles in mind, organizations can maintain robust machine learning models that adapt to changing data environments. This proactive approach not only improves model accuracy but also supports long-term strategic planning.
If you have questions or want to explore drift management strategies further, feel free to reach out and schedule a phone call with our experts. We’re here to help you navigate the challenges of maintaining high-performing machine learning models.
What is drift in machine learning?
Drift in machine learning occurs when a model that once made accurate predictions begins to perform poorly. It doesn’t refer to cars drifting on a racetrack; rather, it describes a change over time in the data environment that makes the original model less effective. Drift happens when the characteristics of the input data change or when the relationship between the data and the target outcome shifts.
Think of it like this: Imagine you built a model based on last year’s customer data. If your customer demographics or buying behavior change this year, the model might not predict trends as accurately. This decline in performance is drift at work.

Drift can show up in several ways. It may occur suddenly, as when a new data collection method is introduced, or it might happen gradually as the underlying patterns slowly evolve. Sometimes, drift follows a recurring pattern, such as seasonal changes. Recognizing drift early helps prevent significant drops in performance.
The four types of drift
Understanding the specific type of drift that affects your model is key to choosing the right countermeasure. In our discussion, we focus on four types: feature drift, label drift, prediction drift, and concept drift.
1. Feature drift
Feature drift refers to changes in the input variables your model relies on. For example, imagine your original training data had mostly female subjects. Over time, if your incoming data shifts to predominantly male subjects, the distribution of your features changes. This shift may cause your model to misinterpret the data, ultimately lowering its accuracy.
2. Label drift
Label drift occurs when the distribution of the outcomes or labels changes. Consider a model that flags spam emails. If the percentage of spam emails increases from 1% to 10%, a model that was trained on data with a lower rate might start missing important signals. In this case, the labels (spam versus not spam) have shifted, and the model needs to be updated.
3. Prediction drift
Prediction drift happens when the model’s own outputs begin to show unexpected trends. This type of drift might occur due to a change in how data is interpreted by the model. For instance, if a model that once predicted a 5% chance of an event starts predicting 10% or 15% without a corresponding change in the input data, prediction drift is likely at work.
4. Concept drift
Concept drift is when the underlying relationship between the input data and the outcome changes. This drift is often the result of external factors. For instance, during an economic downturn, the factors that determine credit card defaults may shift dramatically. Even if the data features remain constant, the model’s predictions may suffer because the concept itself has evolved.

Databricks Demo on YouTube : https://youtu.be/tGckE83S-4s?si=uPUrJ86GayUkI-p4&t=470
By breaking down drift into these four types, you can pinpoint which part of your data environment has changed. Each type of drift requires a slightly different approach to address it.
How to detect and prevent drift
Once you understand what drift is and the ways it can manifest, the next step is detecting it and taking action. The most common strategy is to retrain your model using new data that reflects current conditions. However, knowing when to retrain is critical to avoid unnecessary costs or missed opportunities.
Monitoring your data
You can monitor drift by tracking key metrics that reveal changes in data distribution. For instance, by checking average values, medians, or even the spread of your data, you can see if the input variables begin to stray from their historical patterns. Statistical tests, such as the Kolmogorov-Smirnov test or Jensen-Shannon divergence, can also help quantify these changes.
Tracking model performance
Another method involves keeping an eye on the model’s performance metrics. Metrics like accuracy, the area under the curve (AUC), and root mean square error (RMSE) are reliable indicators of how well your model is doing. If you notice that these metrics decline consistently, it might be time to retrain your model.

Databricks Demo on YouTube: https://youtu.be/tGckE83S-4s?si=0Nhky3lK7WJae2n0&t=654
Using tools for drift detection
Modern tools make drift detection more straightforward. One such tool is Evidently AI, an open-source platform that offers preset evaluations to generate comprehensive drift reports. Evidently AI can produce interactive HTML reports that highlight drift across different aspects of your data, such as feature distributions and performance metrics.
Even better, the tool provides structured outputs. This means you can integrate the results into your workflow. When drift reaches a certain threshold, you might automatically trigger model retraining. This process helps ensure your models remain accurate over time without constant manual oversight.
Best practices for handling drift
Set Clear Thresholds: Decide on the performance metrics that matter most to your business. Set thresholds that trigger a review or retraining process when these metrics drop.
Automate Monitoring: Whenever possible, automate the data and performance monitoring process. Automated alerts can help you react quickly before the drift causes serious issues.
Retrain When Necessary: The rule of thumb is to retrain your model “when you need to.” Some environments change slowly and may require annual retraining. In fast-paced settings, retraining might be needed more frequently.
Use Visual Reports: Visual dashboards and interactive reports make it easier for decision makers to understand the data. They provide a clear picture of when drift occurs, allowing you to take timely action.
Bringing it all together
Drift in machine learning poses a real challenge, but it does not have to be a roadblock. By understanding the types of drift and monitoring key indicators, you can keep your models performing at their best. Whether you choose to monitor manually or set up an automated process, the key is to remain proactive and responsive.
For decision makers, this means investing in the right tools and strategies today can save considerable time and resources tomorrow. For data scientists, it emphasizes the importance of a proactive approach to model management. It’s not about if your model will drift, but when. You must be ready to diagnose and refresh when needed as to minimize downtime, mistakes & costs.

Next steps
If you believe your organization could benefit from enhanced drift monitoring, consider scheduling a phone call with our team. We can help you review your current model management practices and identify opportunities for improvement. A simple discussion can lead to significant gains in model performance and business outcomes.
Key Takeaways
Drift in machine learning refers to a decline in model performance over time due to changes in data or underlying relationships.
Four types of drift—feature, label, prediction, and concept drift—affect models in different ways.
Early detection is crucial. Monitor both your data and performance metrics to catch drift before it impacts your business.
Tools like Evidently AI help generate comprehensive reports and enable automated retraining when performance drops.
The mantra is simple: Retrain only when necessary to balance performance improvements with cost considerations.
By keeping these principles in mind, organizations can maintain robust machine learning models that adapt to changing data environments. This proactive approach not only improves model accuracy but also supports long-term strategic planning.
If you have questions or want to explore drift management strategies further, feel free to reach out and schedule a phone call with our experts. We’re here to help you navigate the challenges of maintaining high-performing machine learning models.
Ready to reach your goals with data?
If you want to reach your goals through the smarter use of data and A.I., you're in the right place.
Ready to reach your goals with data?
If you want to reach your goals through the smarter use of data and A.I., you're in the right place.
Ready to reach your goals with data?
If you want to reach your goals through the smarter use of data and A.I., you're in the right place.
Ready to reach your goals with data?
If you want to reach your goals through the smarter use of data and A.I., you're in the right place.