QUESTION 7 You are requested to estimate a function for South African real imports of goods and services from 1970 to 2013, based on the following potential relationship: R Z . = at BIRGDP + + B 2PZ + & (Equation 1) The variables are: cto Variable name Description Real imports of goods and services (R millions) RGDP Real gross domestic product (R millions) N Import prices (Index) Upon estimation of Equation 1 using OLS, you obtain the following results: In(RZ.) = 8.51 + 0.26In(RGDPt) - 0.29ln(PZt) ta = 4.11; to, =9.27; tB, =-2.37 R2 = 0.9678; Radi = 0.9645 F = 293.28 DW = 1.25 mCorrelation coefficient between RGDP, and PZt: p = 0.05 7.1 Economically evaluate the results above. (2) 7.2 Economically interpret the slope parameters above. (2 ) " 7.3 Statistically evaluate the individual estimated slope parameters. (4) 7.4 Statistically evaluate the joint parameter significance / overall model significance. (2 ) Statistically evaluate the goodness-of-fit of the model. (2) 7.6 Does this model suffer from the problems of multicollinearity and serial correlation? Why/why not? (4) [16] [End of Questions - please turn the page for the Appendices]