Q. Briefly discuss any changes in individual significance levels when using robust standard errors.
Q. Write down the expression for the fitted value of nettfa using the estimated coefficients and standard notation for regressors: inc,inc2,inc3, etc.
Q. Write down the partial derivative of the fitted value with respect to inc; it estimates the effect of a one-unit increase in income.
(c) Plot the predicted average wealth as a function of income for 35-year-old married respondents who are eligible for 401k plan, with 3 persons in the household: