Least-squares models and prediction

What this note covers

1. Fit a least-squares line and read its parts
2. Predict by interpolation
3. Recognise extrapolation and its risk
4. Use residuals to audit a prediction
5. Connect slope, r and r squared
6. Write a bounded prediction and decision
7. Worked least-squares fit: slope, residuals and checked interpolation
8. Worked prediction review: range, residual pattern and model choice

8 sections · 10 key terms & formulas · 6 common mistakes