# Question

Refer to Exercise 11.40. Often in drug evaluations, a logarithmic transformation of the dose levels will yield a linear relationship between the response variable and the independent variable. Let xi be the natural logarithm of the dose levels, and evaluate the regression of the response of the drug in the 15 test tubes to the transformed independent variable: yi = β0 + β1xi + ɛi.

a. Plot the response of the drug versus the natural logarithm of the dose levels. Does it appear that a linear model is appropriate?

b. Fit a linear regression model to these data.

c. From a plot of the residuals, do these appear to be a possible lack of fit of the linear model?

d. Conduct a test for lack of fit of the lineat regression model.

In exercise

a. Plot the response of the drug versus the natural logarithm of the dose levels. Does it appear that a linear model is appropriate?

b. Fit a linear regression model to these data.

c. From a plot of the residuals, do these appear to be a possible lack of fit of the linear model?

d. Conduct a test for lack of fit of the lineat regression model.

In exercise

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