Your First Candidate for a Regression to Identify the Effect

question 5

Multiple Choice

Your first candidate for a regression to identify the effect of X₁ on Y is: Y_i = β₀ + β₁X_1i + β₂X_2i + U_i, where X₂ is a control variable. Suppose a member of your consulting team suggests to you that another variable R_i should be a control that is also included in your regression, in order for you not to be worried about the endogeneity problem. What condition could you credibly test using data on Y, X₁, X₂, and R which could justify the inclusion of R_i as a control in your regression?

• A) R_i has no effect per se on Y_i.
• B) R_i has a strong correlation with X₂.
• C) R_i is exogenous.
• D) spcorr(R_i, Y_i (X_i1, X_i2)) ≠ 0

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Definitions:

Peribrachial Area

A region in the brainstem associated with the processing of sensory information, particularly related to pain and visceral inputs, playing a crucial role in the modulation of autonomic functions.

Medial Pontine Reticular Formation

The Medial Pontine Reticular Formation is a part of the brainstem involved in regulating the sleep-wake cycle and coordinating motor activities.

Raphe Nuclei

A group of nuclei found in the brain stem involved in the regulation of sleep and mood, among other functions.

Neurotransmitters

Neurotransmitters are chemical messengers that transmit signals across a chemical synapse, from one neuron to another target neuron, muscle cell, or gland cell.