The Following Is Not Part of the Extended Least Squares $\sigma _ { u } ^ { 2 }$

question 29

Multiple Choice

The following is not part of the extended least squares assumptions for regression with a single regressor:

• A)var(u_i | X_i)= \(\sigma _ { u } ^ { 2 }\)
• B)E(u_i | X_i)= 0.
• C)the conditional distribution of u_i given X_i is normal.
• D)var(u_i | X_i)= \(\sigma _ { u , i } ^ { 2 }\)

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Definitions:

Randomly Assigned

A process in experimental design where participants are allocated to different groups or conditions by chance, minimizing bias and ensuring each participant has an equal chance of being assigned to any group.

Treatments

In experimental research, different conditions applied to groups to observe and measure the effects.

Observational Study

A research method in which the researcher observes subjects in their natural environment without manipulation or intervention.

Data Collection

The process of gathering and measuring information on targeted variables to answer relevant questions and evaluate outcomes.