Exponential regression, interpolation, extrapolation and reliability of predictions

What this note covers

1. The exponential model in this subject's notation
2. Interpreting a: the initial value
3. Interpreting b as a percentage increase or decrease
4. Interpolation and extrapolation
5. Writing a reliability comment that earns full marks
6. Worked example: fitting, interpreting and predicting from an exponential model
7. Choosing between the two models and reporting the comparison
8. How this is examined in the SACE paper — and what separates a top answer

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