a Suppose that the response variable y is related to the exp

(a) Suppose that the response variable y is related to the explanatory variables x1 and x2 by the regression equation. Complete parts (a) through (f). Y = 3 + .6 x1 - 1.4x2 (b) Construct a graph showing the relationship between the expected value of y and x1 for x2 = 10, 20 and 30. choose the correct answer below (c) How can we tell from the graphs alone that there is no interaction between x1 and x2? (d) Construct a graph showing the relationship between the expected value of y and x1 for x2 10,20, and 30 with the interaction term 0.05x1,x2 added to the regression equation. Choose the correct answer below. (e) Construct a graph showing the relationship between the expected value of y and x2 for x1 = 40,50, and 60 with the interaction term 0.05 x1x2, added to the regression equation. Choose the correct answer below. (f) flow do the graphs from parts (d) and (e) differ from the graphs in parts (a) and (b)? A. The slopes of the lines are now negative in the graphs from parts (d) and (e). B. The y-intercepts of the lines are now equal in the graphs from parts (d) and (e). C. The lines are no longer parallel in the graphs from parts (d) and (e). D. The lines are now parallel in the graphs from parts (d) and (e).

Solution

(a)B

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(b)C

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(c)D

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(d)B

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(e)D

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(f)B