# Question: Refer to the data of Exercise 12 9 Often a logarithmic

Refer to the data of Exercise 12.9. Often a logarithmic transformation can be used on the dose levels to linearize the response with respect to the independent variable. a. Obtain the natural logarithms of the five dose levels, ln(dose)

b. Let x = ln( dose), fit the model y = β0 + β1x + ɛ

c. Compare your results to the fitted models in Exercise 12.9. Does the logarithmic transformation provide a better fit than the models in Exercise 12.9?

In exercise

Dose Level Response

2…………………………... 5, 7, 3

4………………………. 10, 12, 14

8………………………. 15, 17, 18

16……………………... 20, 21, 19

32……………………... 23, 24, 29

b. Let x = ln( dose), fit the model y = β0 + β1x + ɛ

c. Compare your results to the fitted models in Exercise 12.9. Does the logarithmic transformation provide a better fit than the models in Exercise 12.9?

In exercise

Dose Level Response

2…………………………... 5, 7, 3

4………………………. 10, 12, 14

8………………………. 15, 17, 18

16……………………... 20, 21, 19

32……………………... 23, 24, 29

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