Using the data of Problem 15.6 on page 637, stored in Tomato, perform a natural logarithm transformation of the dependent variable (yield). Using the transformed dependent variable and the fertilizer application rate as the independent variable, perform a regression analysis.
a. State the regression equation.
b. Predict the yield when 55 pounds of fertilizer is applied per 1,000 square feet.
c. Perform a residual analysis of the results and determine whether the regression assumptions are valid.
d. At the 0.05 level of significance, is there a significant relationship between the natural logarithm of yield and the fertilizer application rate?
e. Interpret the meaning of the coefficient of determination, r2, in this problem.
f. Compute the adjusted r2.
g. Compare your results with those in Problem 15.6. Which model is better? Why?