The TSLS Estimator Is

question 12

Multiple Choice

The TSLS estimator is

• A)(X'X)^-1 X'Y
• B)(X'Z(Z'Z)^-1 Z'X)^-1 X'Z(Z'Z)^-1 Z' Y
• C)(XΩ^-1X)^-1(XΩ^-1Y)
• D)(X'P_z)^-1P_zY

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Definitions:

Tunic

A layer or covering, often referred to in biology as the outer, fibrous covering of organisms such as tunicates or the covering around certain seeds.

Body Covering

The outermost layer or material that covers the body of an organism, such as skin, fur, feathers, or scales.

Venom

A toxic substance secreted by animals, such as snakes and spiders, often used to immobilize or kill prey and for defense.

Stingrays

Marine cartilaginous fish known for their flat bodies and long, whip-like tails equipped with venomous stingers, used for defense.