A Weak Instrument Is an Instrumental Variable

question 4

Multiple Choice

A weak instrument is an instrumental variable:

• A) whose distribution is non-normal.
• B) whose partial correlation with the outcome is small.
• C) whose partial correlation with the (endogenous) treatment variable is small.
• D) that suffers from heteroscedasticity.

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Definitions:

Expectancy Theory

A psychological theory stating that an individual's motivation to engage in an activity is influenced by the expected outcome and the value of that outcome to the individual.

Expectancy

In psychology, a theory that explains the motivation behind choices, suggesting that people are motivated to act in a certain way because they expect their actions will lead to their desired goal.

Instrumentality

In expectancy theory, the belief that a certain level of performance will lead to a specific outcome or reward.

Effort

The amount of energy, work, or concentration applied towards a task or goal.