Use the information given in Problem 2 of Chapter 8, as well as the computer output given here, to answer the following questions about the data from that problem.
a. Conduct overall regression F tests for these three models: Y regressed on X1 and X2; Y regressed on X1 alone; and Y regressed on X2 alone. Based on your answers, how would you rate the importance of the two variables in predicting Y? Comment on how your answer compares with the answer to Problem 2(b) in Chapter 8.
b. Provide variables-added-in-order tests for both variables, with thinking disturbances (X1) added first. Use α = .05.
c. Provide variables-added-in-order tests for both variables, with hostile suspiciousness (X2) added first. Use α = .05.
d. Provide a table of variables-added-last tests.
e. What, if any, differences are present in the approaches in parts (a) through (d)?
f. Which predictors appear to be necessary? Why?

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Y Regressed on X1 and X2 DF Sum of Squares Mean Square F Value Pr> F Source Model Error Corrected Total 2753,87136 11037 29845 13791.16981 1376.93568 220.74597 6.24 0.0038 50 52 R-Square Coeff Var Root MSEY Mean 0.199684 65.45708 14.85752 22.69811 Mean Square FValue Pr> F Source DF X1 X2 Type I SS 1535.856965 1218.014394 1535.856965 6.96 0.0111 1218.014394552 0.0228 Mean Square F ValuePr>F Source X1 X2 DFType III SS 12596.024025 2596.024025 11.76 0.0012 1 1218.014394 5.52 00228 1218.014394 Estimate Standard Error Value Pr> It Parameter Intercept X1 X2 -0.63535020 20.96833367 0.03 0.9759 6 8350964 343 0002 2.35 0.0228 23.45143521 0726020 301092484 .3 00228