A residual plot from a linear model shows a clear funnel shape (increasing spread).
The most appropriate response is:
- A
Fit a higher-order polynomial
- B
Switch to a categorical variable
- Ccheck_circle
Consider a transformation (e.g., log of y) to stabilize spread
- D
Increase the sample size
Explanation
Heteroscedasticity often calls for a variance-stabilizing transformation such as log(y) or sqrt(y).