World economyThe world economy or global economy is the economy of all humans of the world, referring to the global economic system, which includes all economic activities which are conducted both within and between nations, including production, consumption, economic management, work in general, exchange of financial values and trade of goods and services. In some contexts, the two terms are distinct "international" or "global economy" being measured separately and distinguished from national economies, while the "world economy" is simply an aggregate of the separate countries' measurements.
Welfare economicsWelfare economics is a field of economics that applies microeconomic techniques to evaluate the overall well-being (welfare) of a society. This evaluation is typically done at the economy-wide level, and attempts to assess the distribution of resources and opportunities among members of society. The principles of welfare economics are often used to inform public economics, which focuses on the ways in which government intervention can improve social welfare.
Pigouvian taxA Pigouvian tax (also spelled Pigovian tax) is a tax on any market activity that generates negative externalities (i.e., external costs incurred by the producer that are not included in the market price). The tax is normally set by the government to correct an undesirable or inefficient market outcome (a market failure) and does so by being set equal to the external marginal cost of the negative externalities. In the presence of negative externalities, social cost includes private cost and external cost caused by negative externalities.
