black market
A situation in which products are sold at prices that violate a legal price
control.
utility
The satisfaction that a consumer receives from consuming some good or
service.
total utility
The consumer’s total satisfaction resulting from the consumption of a
given product.
marginal utility
The additional satisfaction obtained from consuming one additional unit
of a product.
real income
Income expressed in terms of the purchasing power of money income—
that is, the quantity of goods and services that can be purchased with the
money income.
substitution effect
The change in the quantity of a product demanded resulting from a
change in its relative price (holding real income constant).
income effect