Microeconomics

Microeconomics (from Greek: μικρό-ς // small, little and οικονομία /ikono΄mia/ economy) is a branch of economics that studies how households and firms make decisions to allocate limited resources,^[1] typically in markets where goods or services are being bought and sold. Microeconomics examines how these decisions and behaviours affect the supply and demand for goods and services, which determines prices; and how prices, in turn, determine the supply and demand of goods and services.^[2][3]

This is a contrast to macroeconomics, which involves the "sum total of economic activity, dealing with the issues of growth, inflation and unemployment, and with national economic policies relating to these issues".^[2] Macroeconomics also deals with the effects of government actions (such as changing taxation levels) on them.^[4] Particularly in the wake of the Lucas critique, much of modern macroeconomic theory has been built upon 'microfoundations' — i.e. based upon basic assumptions about micro-level behaviour.

One of the goals of microeconomics is to analyze market mechanisms that establish relative prices amongst goods and services and allocation of limited resources amongst many alternative uses. Microeconomics analyzes market failure, where markets fail to produce efficient results, as well as describing the theoretical conditions needed for perfect competition. Significant fields of study in microeconomics include general equilibrium, markets under asymmetric information, choice under uncertainty and economic applications of game theory. Also considered is the elasticity of products within the market system.

Assumptions and definitions

The theory of supply and demand usually assumes that markets are perfectly competitive. This implies that there are many buyers and sellers in the market and none of them has the capacity to significantly influence prices of goods and services. In many real-life transactions, the assumption fails because some individual buyers or sellers have the ability to influence prices. Quite often a sophisticated analysis is required to understand the demand-supply equation of a good model. However, the theory works well in simple situations.

Mainstream economics does not assume a priori that markets are preferable to other forms of social organization. In fact, much analysis is devoted to cases where so-called market failures lead to resource allocation that is suboptimal by some standard (highways are the classic example, profitable to all for use but not directly profitable for anyone to finance). In such cases, economists may attempt to find policies that will avoid waste directly by government control, indirectly by regulation that induces market participants to act in a manner consistent with optimal welfare, or by creating "missing markets" to enable efficient trading where none had previously existed. This is studied in the field of collective action. It also must be noted that "optimal welfare" usually takes on a Paretian norm, which in its mathematical application of Kaldor-Hicks Method, does not stay consistent with the Utilitarian norm within the normative side of economics which studies collective action, namely public choice. Market failure in positive economics (microeconomics) is limited in implications without mixing the belief of the economist and his or her theory.

The demand for various commodities by individuals is generally thought of as the outcome of a utility-maximizing process. The interpretation of this relationship between price and quantity demanded of a given good is that, given all the other goods and constraints, this set of choices is that one which makes the consumer happiest.