\begin{question}
Under the assumptions of the Gauss-Markov theorem the errors
of a linear regression model need to be:
\begin{answerlist}
  \item independent
  \item uncorrelated
  \item normally distributed
  \item identically distributed
  \item homoscedastic
  \item zero
\end{answerlist}
\end{question}

\begin{solution}
Under the assumptions of the Gauss-Markov theorem the errors of a linear
regression model need to be uncorrelated, homoscedastic, and with mean zero.
\begin{answerlist}
  \item False. Independence is not assumed, only lack of correlation.
  \item True. The errors need to be uncorrelated.
  \item False. No distribution assumption is needed.
  \item False. No distribution assumption is needed.
  \item True. The errors need to be homoscedastic with finite variance.
  \item False. Only their conditional expectation needs to be zero.
\end{answerlist}
\end{solution}

\exname{Gauss-Markov assumptions}
\extype{mchoice}
\exsolution{010010}
\exshuffle{5}