Hinis for marginal revenue: the change in revenue possible from producing and selling an additional unit of output. For a firm, the marginal revenue associated with producing and selling additional output is calculated as the change in total revenues divided by the respective change in output. market: a collection of demanders and suppliers who exchange goods and services. market failure: when prices fail to adjust in ways that allow the efficient distribution or production of goods and services within a market. Market failures can occur when consumers (free riders) obtain public goods without compensating the good’s suppliers or when externalities are present, and can become an argument for allowing government intervention in the economy. market power: the ability of a firm to set prices in excess of marginal cost. Market power is sometimes also referred to as monopoly power. Hinis 2016.