An Introduction to Statistical Learning: With Applications in Python, Gareth James, Daniela Witten, Trevor Hastie, Robert Tibshirani, and Jonathan Taylor, 2023 (Springer) - A highly regarded introductory textbook that covers fundamental concepts of statistical learning, including linear regression, training-test splitting, and evaluation metrics for regression problems.
Regression metrics, scikit-learn developers, 2024 - Official documentation detailing the definitions and implementation of various regression performance metrics, such as MAE, MSE, and R-squared, essential for model evaluation.
Applied Predictive Modeling, Max Kuhn and Kjell Johnson, 2013 (Springer)DOI: 10.1007/978-1-4614-6849-3 - This book provides practical guidance on the entire process of building and evaluating predictive models, with specific attention to robust data splitting techniques and the appropriate use of performance metrics.