Suppose you fit the model y = PO + Plxl + P~X: + hx2 + P4~1~2 +

to n = 25 data points with the following results:

SSE = .41 R2 = .83 .

a. Is there sufficient evidence to conclude that at least one of the parameters PI, P2, P3, or P4 is nonzero?

Test using a = .05.

h. Test H,,: = 0 against Ha: PI < 0. Use a = .05.

c. Test H,,: p2 = 0 against Ha: p2 > 0. Use n = .05.

d. Test H,,: p, = 0 against Ha: p, # 0. Use n = .05.