Less Red Meat! One desirable dietary change if you want to “eat right,” is to reduce...

Less Red Meat! One desirable dietary change if you want to “eat right,” is to reduce the intake of red meat and to substitute poultry or fish. Researchers tracked beef and chicken consumption, y (in annual pounds per person), and found the consumption of beef declining and the consumption of chicken increasing over a period of 7 years. A summary of their data is shown in the table.

Consider fitting the following model, which allows for simultaneously fitting two simple linear regression lines:

where y is the annual meat (either beef or chicken) consumption per person per year,

a. How well does the model fit? Use any relevant statistics and diagnostic tools from the printout to answer this question.

b. Write the equations of the two straight lines that describe the trend in consumption over the period of 7 years for beef and for chicken.

c. Use the prediction equation to find a point estimate of the average per-person beef consumption in year 8. Compare this value with the value labeled “Fit” in the printout.

d. Use the printout to find a 95% confidence interval for the average per-person beef consumption in year 8. What is the 95% prediction interval for the perperson beef consumption in year 8? Is there any problem with the validity of the 95% confidence level for these intervals?