Least-squares regression line: equation, interpolation and extrapolation

What this note covers

1. What is the least-squares regression line?
2. Determining the equation — by hand and by technology
3. Worked example — finding and interpreting the regression equation
4. Using the equation to make predictions
5. Interpolation vs. extrapolation — a deeper look
6. Interpreting the gradient and intercept in context
7. Exam technique and common pitfalls

7 sections · 12 key terms & formulas · 6 common mistakes