Using data for the years 2005 to 2019 for US, an economist obtained the following demand function for automobiles: Yt: 5266 + 0.857 X₁ R² = 0.26
se = (0.02 ) (0.561)
Y= retail sales of passenger cars (thousands) and X = the real disposable income (billions of 2017 rand) Q.4.1 Construct a 90% confidence interval for β (Xt). Q.4.2 Test the following hypothesis at 5% level using a t-test: H: β = 0 H: β # 0