# Question

Refer to Exercise 13.54. The agronomist is concerned that there may be a distinct difference between the models for land in West Texas and for land in East Texas. Observations 1– 23 are data values from East Texas and 24- 46 are from West Texas.

a. At the α = .05 level, are there differences between the models for the two regions?

b. For each of the two regions, produce a 95% confidence interval on the average evaporation for the values of the explanatory variables given in Exercise 13.54.

c. Was the there a large difference in the point estimators for the two regions? Compare the widths of the intervals for the two regions.

In exercise

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a. At the α = .05 level, are there differences between the models for the two regions?

b. For each of the two regions, produce a 95% confidence interval on the average evaporation for the values of the explanatory variables given in Exercise 13.54.

c. Was the there a large difference in the point estimators for the two regions? Compare the widths of the intervals for the two regions.

In exercise

QUESTION CONTINUE TO NEXT PAGE……

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