2. Estimate a regression of growth on tradeshr with heteroskedasticity-robust standard errors. a) What is the coefficient on tradeshr? Explain in words what it means. Is the numerical value of your estimate large or small in an economic (real-world) sense? b) Graph the data points and the estimated regression line. c) Is the slope coefficient statistically significantly different from zero at the 5% significance level? Show how you reach this conclusion. d) Report the 95% confidence interval for 1, the slope of the population regression line. e) What is the R of this regression? What does this mean? f) Compute the correlation coefficient between growth and tradeshr, and compare its square to the R. How are the correlation coefficient and the R related? g) What is the value of the root mean squared error of the regression? What does this mean? h) Based on your graph from (b), does the regression error appear to be homoskedastic or heteroskedastic? i) Estimate the regression again with homoskedasticity-only standard errors. Compare the results to what you obtained with the heteroskedasticity-robust standard errors. What is different? j) You should see an outlier in the data set. Rerun the regression (with the "robust" option), dropping the outlier. Does dropping the outlier make a qualitative difference to your results? Explain. k) What is the outlying observation? Considering the economics of the relation you are investigating, in your judgment should that outlier be omitted from the regression? (You might need to do a bit of research about that outlier to answer this question properly.)