The Notation for Panel Data Is $\left( X _ { i t } , Y _ { i t } \right) , i = 1 , \ldots , n \text { and } t = 1 , \ldots , T$

question 20

Multiple Choice

The notation for panel data is $\left( X _ { i t } , Y _ { i t } \right) , i = 1 , \ldots , n \text { and } t = 1 , \ldots , T$
because

• A) we take into account that the entities included in the panel change over time and are replaced by others.
• B) the X 's represent the observed effects and the Y the omitted fixed effects.
• C) there are n entities and T time periods.
• D) n has to be larger than T for the OLS estimator to exist.

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Definitions:

Tungsten Lightbulb

A type of incandescent light bulb that uses a tungsten filament to produce light when heated by an electric current.

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A measure of light intensity now largely replaced by the metric unit, candela.

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An energy-efficient lighting device using mercury vapor to emit UV light, which then causes a phosphorescent coating to glow.

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