# Question: Refer to Exercise 13 17 a Using an indicator variable fit a

Refer to Exercise 13.17.

a. Using an indicator variable, fit a single model to the hops data for varieties Fuggle and Northern Brewer.

b. Using your results from part (a), obtain separate prediction equations for varieties Fuggle and Northern Brewer.

c. Interpret the values of the coefficients (βs) in the model.

d. Using your prediction equations in part (b), estimate the mean alpha acid percent-age when the atmospheric conditions are a mean temperature of 19° C and a mean sunshine of 6.5. How different are the two estimates?

e. Place 95% confidence intervals on your estimates.

In exercise

a. Using an indicator variable, fit a single model to the hops data for varieties Fuggle and Northern Brewer.

b. Using your results from part (a), obtain separate prediction equations for varieties Fuggle and Northern Brewer.

c. Interpret the values of the coefficients (βs) in the model.

d. Using your prediction equations in part (b), estimate the mean alpha acid percent-age when the atmospheric conditions are a mean temperature of 19° C and a mean sunshine of 6.5. How different are the two estimates?

e. Place 95% confidence intervals on your estimates.

In exercise

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