Lesson Introduction

Hello! Today, we will learn about the R-squared metric, a vital measure in machine learning. Have you ever wondered how to measure how well your model fits the real data? That’s exactly what the R-squared metric helps with! By the end of this lesson, you'll understand what R-squared is, why it’s essential, and how to calculate it using Python.

Understanding R-squared

What is R-squared (R²)?

Imagine you're predicting how the height of children changes with age. R-squared, also called the coefficient of determination, helps us understand how well our model explains this variability in height based on age.

The formula for R-squared is:

R2=1−SSresSStotR^2 = 1 - \frac{SS_{res}}{SS_{tot}}, where:

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