Using the data of Problem 15.6 on page 581, stored in Cost Estimation, perform a square-root transformation of the independent variable (unit production). Using total cost as the dependent variable and the transformed independent variable, perform a regression analysis, a. State the regression equation.
b. Predict the total cost when production is 145 units.
c. Perform a residual analysis of the results and determine whether the regression model is valid.
d. At the 0.05 level of significance, is there a significant relationship between total cost and the square root of unit production?
e. Interpret the meaning of the coefficient of determination, r2, in this problem.
f. Compute the adjusted r2.
g. Compare your results with those of Problems 15.6 and 15.12. Which model is best? Why?