If People Who Drop Out of Study Are Systematically Different

question 24

Multiple Choice

If people who drop out of study are systematically different from those who stay, we have which threat to validity?

• A) selection
• B) mortality
• C) regression to the mean
• D) maturation

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Definitions:

Commodity Money

Anything that serves both as money and as a commodity; money that has intrinsic value such as gold or silver coins.

Double Coincidence

A situation in a barter system where two parties each hold an item the other wants, necessitating an exact match to complete an exchange.

Trade

The exchange of goods, services, or both between countries or individuals, allowing for the specialization and efficiency benefits.

Relative Values

A measure of the worth or importance of one thing in comparison to another, often used in economics to compare the value of different commodities or services.