The data file German Income shows 22 annual observations from the Federal Republic of Germany on percentage change in wages and salaries (y), productivity growth (x1), and the rate of inflation (x2), as measured by the gross national product price deflator. Estimate by least squares the following regression:
yt = β0 + β1x1t + β2x2t + εt
Write a report summarizing your findings, including a test for heteroscedasticity and a test for autocorrelated errors.