Consider the following regression model, Y;=B1+B2X12+ +BxX ik+ ej where E[ e,|x;]=0 and Var(e,|x,) depends on the value of ... i.e., Var(e,|x)= o². Choose the correct statement. a. To get around the...

Extracted text: Consider the following regression model, Y;=B1+B2X12+ +BxX ik+ ej where E[ e,|x;]=0 and Var(e,|x,) depends on the value of ... i.e., Var(e,|x)= o². Choose the correct statement. a. To get around the problem, we often assume that e; is normally distributed. O D. To fix the problem, we need to have an instrumental variable. O C. This problem implies that errors are correlated with one of (x2. ..., x ik): d. If we assume Var(e;|x) = o2, the confidence interval is not valid. e. None of the above is correct.