- [Maximum mark: 6]
A vet wants to find a relationship between the age in days of a breed of puppy (d) and its weight in kg (w).
To do this he collects a large quantity of data and plots two graphs. He finds the regression line for each graph. His results are summarized in the table.
| Horizontal axis | Vertical axis | Gradient | Intercept on vertical axis | R² | |
|---|---|---|---|---|---|
| Graph 1 | d | ln w | 0.00571 | 1.54 | 0.72 |
| Graph 2 | ln d | ln w | 0.302 | 0.693 | 0.95 |
Based on these results, find the best of the two possible relationships between w and d. Express your relationship in the form w = f(d) where f is a simplified expression. Justify your choice of expression. [6]