Snow geese feeding trial. Refer to the Journal of Applied Ecology (Vol. 32, 1995) study of the feeding habits of baby snow geese, Exercise. The data on gosling weight change, digestion efficiency, acid-detergent fiber (all measured as percentages) and diet (plants or duck chow) for 42 feeding trials are saved in the SNOWGEESE file. (The table shows selected observations.) The botanists were interested in predicting weight change (y) as a function of the other variables. The first-order model E(y) = β₀ + β₁x₁ + β₂x₂, where x₁ is digestion efficiency and x2 is acid-detergent fiber, was fit to the data. The MINITAB printout is given below.

(a) Find the least squares prediction equation for weight change, y.

(b) Interpret the β-estimates in the equation, part a.

(c) Conduct the F-test for overall model adequacy using α = .01.

(d) Find and interpret the values of R₂ and R₂ a. Which is the preferred measure of model fit?

(e) Conduct a test to determine if digestion efficiency, x₁, is a useful linear predictor of weight change. Use α = .01.

(f) Form a 99% confidence interval for β₂. Interpret the result.