The Sampling Variance for the Instrumental Variables (IV) Estimator Is

question 19

Multiple Choice

The sampling variance for the instrumental variables (IV) estimator is larger than the variance for the ordinary least square estimators (OLS) because _____.

• A)R² > 1
• B)R² < 0
• C)R² = 1
• D)R² < 1

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Definitions:

Atmospheric Oxygen

The oxygen gas (O2) present in the Earth's atmosphere, essential for the respiratory processes of most living organisms.

Photosynthesizing Bacteria

Microorganisms that convert light energy into chemical energy through the process of photosynthesis.

Terrestrial Plants

Plants that grow on land, as opposed to aquatic (water-based) or epiphytic (growing on other plants) plants.

Primitive Atmosphere

The early atmosphere of Earth, which was very different in composition from the current one, possibly composed of gases such as methane, ammonia, and water vapor.