Data Leakage: Your 99% Accuracy Model is a Lie
Last Updated on October 15, 2025 by Editorial Team
Author(s): Rohan Mistry
Originally published on Towards AI.
Training Accuracy: 99%. Production Accuracy: 53%. Welcome to Data Leakage Hell.
You spent 3 months building the perfect model.
The article discusses the challenges of data leakage in machine learning, where a model achieves high accuracy during training but drastically fails in production due to flawed data handling and feature selection. It emphasizes the common pitfalls that lead to data leakage across various applications, including fraud detection, churn prediction, and stock forecasting, providing readers with insights on how to identify and prevent it. The author outlines practical checklists and strategies to ensure robust model performance, reinforcing the importance of using only training data features that would be available at the prediction time.
Read the full blog for free on Medium.
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