(Requires Appendix material)When the fifth assumption in the Fixed Effects regression (cov (uit,uis Xit,Xis)= 0 for t ≠ s)is violated,then
A)using heteroskedastic-robust standard errors is not sufficient for correct statistical inference when using OLS.
B)the OLS estimator does not exist.
C)you can use the simple homoskedasticity-only standard errors calculated in your regression package.
D)you cannot use fixed time effects in your estimation.

Question

(Requires Appendix material)When the fifth assumption in the Fixed Effects regression (cov (uit,uis  Xit,Xis)= 0 for t ≠ s)is violated,then
A)using heteroskedastic-robust standard errors is not sufficient for correct statistical inference when using OLS. 
B)the OLS estimator does not exist. 
C)you can use the simple homoskedasticity-only standard errors calculated in your regression package. 
D)you cannot use fixed time effects in your estimation.

Quizplus · Accepted Answer

The Answer of (Requires Appendix material)When the fifth assumption in the Fixed Effects regression (cov (uit,uis  Xit,Xis)= 0 for t ≠ s)is violated,then
A)using heteroskedastic-robust standard errors is not sufficient for correct statistical inference when using OLS. 
B)the OLS estimator does not exist. 
C)you can use the simple homoskedasticity-only standard errors calculated in your regression package. 
D)you cannot use fixed time effects in your estimation.

(Requires Appendix Material)When the Fifth Assumption in the Fixed Effects