# Question

Refer to Exercise 13.54.

a. Formulate a new model using a variable selection procedure with AIC and then BIC as the criterion to select the independent variables. Was there a large difference in the selected variables for the two methods?

b. Compare the standard errors of the estimated βs in the model selected by BIC to those in the full model fit in Exercise 13.54. Was there an increase or a decrease in the standard errors of the estimated βs?

c. Produce a 95% confidence interval on the average evaporation for the values of the explanatory variables given in Exercise 13.54. Was there a large difference in the two point estimators? Compare the widths of the two intervals.

In exercise

QUESTION CONTINUE TO NEXT PAGE……

a. Formulate a new model using a variable selection procedure with AIC and then BIC as the criterion to select the independent variables. Was there a large difference in the selected variables for the two methods?

b. Compare the standard errors of the estimated βs in the model selected by BIC to those in the full model fit in Exercise 13.54. Was there an increase or a decrease in the standard errors of the estimated βs?

c. Produce a 95% confidence interval on the average evaporation for the values of the explanatory variables given in Exercise 13.54. Was there a large difference in the two point estimators? Compare the widths of the two intervals.

In exercise

QUESTION CONTINUE TO NEXT PAGE……

## Answer to relevant Questions

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