In a multiple regression with 40 observations the following

Question

In a multiple regression with 40 observations, the following sample regression equation is obtained: y = 12.8 + 2.6x₁ - 1.2x₂ with se = 5.84. Also, when x₁ equals 15 and x₂ equals 6, se(y₀) = 2.20.

a. Construct a 95% confidence interval for E(y) if x₁ equals 15 and x₂ equals 6.

b. Construct a 95% prediction interval for y if x₁ equals 15 and x₂ equals 6.

c. Which interval is wider? Explain.