Let W Be the Included Exogenous Variables in a Regression

question 1

Multiple Choice

Let W be the included exogenous variables in a regression function that also has endogenous regressors (X) .The W variables can

• A)be control variables
• B)have the property E(ui|Wi)= 0
• C)make an instrument uncorrelated with u
• D)all of the above

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Definitions:

Puberty

The developmental period in which a child's body transitions into an adult body capable of sexual reproduction.

Underarm Hair

Hair that grows under the arms, which begins to appear during puberty as a result of hormonal changes in the body.

Growth Spurt

A rapid increase in physical growth during puberty or other developmental stages.

Secondary Sex Characteristics

Traits that emerge during puberty, which are not directly involved in reproduction, but distinguish between the sexes.