Concept explainers
Suppose you fit the multiple regression model
y =β0 + β1 x1 + β2x2 + β3x3 + ε
to n = 30 data points and obtain the following result:
The estimated standard errors of
a. Test the null hypothesis H0: β2 = 0 against the alternative hypothesis Ha: β2 ≠ 0. Use α = .05.
b. Test the null hypothesis H0: β3 = 0 against the alternative hypothesis Ha: β3 ≠ 0. Use α = .05.
c. The null hypothesis H0: β2 = 0 is not rejected. In contrast, the null hypothesis H0: β3 = 0 is rejected. Explain how this can happen even though
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Statistics for Business and Economics (13th Edition)
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