# 3. Linear Regression
## Learning Objectives
- Perform linear regression with a **single predictor variable.**
- Estimate the **standard error** of regression coefficients.
- Evaluate the **goodness of fit** of a regression.
- Perform linear regression with **multiple predictor variables.**
- Evaluate the **relative importance of variables** in a multiple linear regression.
- Include **interaction effects** in a multiple linear regression.
- Perform linear regression with **qualitative predictor variables.**
- Model **non-linear relationships** using polynomial regression.
- Identify **non-linearity** in a data set.
- Compare and contrast linear regression with **KNN regression.**