A. Compare the regression diagnostics (Studentized residual, leverage, and Cook’s distance) computed in Problem 4.12 above with those obtained using a quadratic fit to the same data (see Problem...

A. Compare the regression diagnostics (Studentized residual, leverage, and Cook’s distance) computed in Problem 4.12 above with those obtained using a quadratic fit to the same data (see Problem 4.13). B. Explain any differences.

Problem 4.12

Evaluate the goodness of the fit of the linear model used to relate antibiotic effectiveness to blood level of the antibiotic in Problem 2.4 (data in Table D-3, Appendix D). If the linear model is not appropriate, propose a better model.

Table D-3

Table D-3