The Following Is Not One of the Gauss-Markov Conditions:
A)var(u_i $\sigma _ { u } ^ { 2 }$

question 13

Multiple Choice

The following is not one of the Gauss-Markov conditions:

• A)var(u_i | X₁,…, X_n)= \(\sigma _ { u } ^ { 2 }\) , 0 < \(\sigma _ { u } ^ { 2 }\) < ? for i = 1,…, n,
• B)the errors are normally distributed.
• C)E(u_iu_j | X₁,…, X_n)= 0, i = 1,…, n, j = 1,..., n, i ? j
• D)E(u_i | X₁,…, X_n)= 0

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Definitions:

Natural Sampling Variation

The variability observed in sample statistics that occurs naturally because every sample differs due to the random selection of observations.

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Null Hypothesis

A statistical hypothesis that assumes no significant difference or effect in a particular test, used as a starting point for experimentation.