Made up data (will give very high R2)

Y X1 X2 X3 X4

27 2 10 b q

43 8 5 a p

55 5 6 b p

84 9 8 b p

88 11 4 b q

42 10 10 a r

34 4 18 a p

16 1 19 b q

71 9 2 b q

39 4 19 b r

68 8 11 b r

74 10 11 b q

96 12 7 b r

42 5 20 b q

25 3 10 a r

63 12 6 a p

49 9 2 a p

83 10 19 b r

83 8 2 b p

28 1 11 b p

48 8 8 a p

99 11 6 b p

15 4 19 a q

39 6 11 a r

82 10 10 b r

1. Do a regression with X1, X2, X3, and X4. Interpret results.

2. Include an interaction between X1 and X3, then X1 and X4. Interpret results; how do results differ from those in (1)?

3. From the results in (2), how would you report the effect of X1?