In economics

Economics

Economics is the social science that analyzes the production, distribution, and consumption of goods and services. The term economics comes from the Ancient Greek from + , hence "rules of the house"...

, market structure (also known as the number of firms producing identical products).

• Monopolistic competition
  Monopolistic competition
  Monopolistic competition is imperfect competition where many competing producers sell products that are differentiated from one another...
  
  , also called competitive market, where there are a large number of firms, each having a small proportion of the market share and slightly differentiated products.
• Oligopoly
  Oligopoly
  An oligopoly is a market form in which a market or industry is dominated by a small number of sellers . The word is derived, by analogy with "monopoly", from the Greek ὀλίγοι "few" + πόλειν "to sell". Because there are few sellers, each oligopolist is likely to be aware of the actions of the others...
  
  , in which a market is dominated by a small number of firms that together control the majority of the market share.
• Duopoly
  Duopoly
  A true duopoly is a specific type of oligopoly where only two producers exist in one market. In reality, this definition is generally used where only two firms have dominant control over a market...
  
  , a special case of an oligopoly with two firms.
• Oligopsony
  Oligopsony
  An oligopsony is a market form in which the number of buyers is small while the number of sellers in theory could be large. This typically happens in a market for inputs where numerous suppliers are competing to sell their product to a small number of buyers...
  
  , a market where many sellers can be present but meet only a few buyers.
• Monopoly
  Monopoly
  A monopoly exists when a specific person or enterprise is the only supplier of a particular commodity...
  
  , where there is only one provider of a product or service.
• Natural monopoly
  Natural monopoly
  A monopoly describes a situation where all sales in a market are undertaken by a single firm. A natural monopoly by contrast is a condition on the cost-technology of an industry whereby it is most efficient for production to be concentrated in a single form...
  
  , a monopoly in which economies of scale
  Economies of scale
  Economies of scale, in microeconomics, refers to the cost advantages that an enterprise obtains due to expansion. There are factors that cause a producer’s average cost per unit to fall as the scale of output is increased. "Economies of scale" is a long run concept and refers to reductions in unit...
  
   cause efficiency to increase continuously with the size of the firm. A firm is a natural monopoly if it is able to serve the entire market demand at a lower cost than any combination of two or more smaller, more specialized firms.
• Monopsony
  Monopsony
  In economics, a monopsony is a market form in which only one buyer faces many sellers. It is an example of imperfect competition, similar to a monopoly, in which only one seller faces many buyers...
  
  , when there is only one buyer in a market.
• Perfect competition
  Perfect competition
  In economic theory, perfect competition describes markets such that no participants are large enough to have the market power to set the price of a homogeneous product. Because the conditions for perfect competition are strict, there are few if any perfectly competitive markets...
  
   is a theoretical market structure that features unlimited contestability (or no barriers to entry
  Barriers to entry
  In theories of competition in economics, barriers to entry are obstacles that make it difficult to enter a given market. The term can refer to hindrances a firm faces in trying to enter a market or industry - such as government regulation, or a large, established firm taking advantage of economies...
  
  ), an unlimited number of producers and consumers, and a perfectly elastic demand curve
  Demand curve
  In economics, the demand curve is the graph depicting the relationship between the price of a certain commodity, and the amount of it that consumers are willing and able to purchase at that given price. It is a graphic representation of a demand schedule...
  
  .

The imperfectly competitive structure is quite identical to the realistic market conditions where some monopolistic competitors

Monopolistic competition

Monopolistic competition is imperfect competition where many competing producers sell products that are differentiated from one another...

, monopolists

Monopoly

A monopoly exists when a specific person or enterprise is the only supplier of a particular commodity...

, oligopolists

Oligopoly

An oligopoly is a market form in which a market or industry is dominated by a small number of sellers . The word is derived, by analogy with "monopoly", from the Greek ὀλίγοι "few" + πόλειν "to sell". Because there are few sellers, each oligopolist is likely to be aware of the actions of the others...

, and duopolists

Duopoly

A true duopoly is a specific type of oligopoly where only two producers exist in one market. In reality, this definition is generally used where only two firms have dominant control over a market...

 exist and dominate the market conditions. The elements of Market Structure include the number and size distribution of firms, entry conditions, and the extent of differentiation.

These somewhat abstract concerns tend to determine some but not all details of a specific concrete market system

Market system

A market system is any systematic process enabling many market players to bid and ask: helping bidders and sellers interact and make deals. It is not just the price mechanism but the entire system of regulation, qualification, credentials, reputations and clearing that surrounds that mechanism and...

 where buyers and sellers actually meet and commit to trade

Trade

Trade is the transfer of ownership of goods and services from one person or entity to another. Trade is sometimes loosely called commerce or financial transaction or barter. A network that allows trade is called a market. The original form of trade was barter, the direct exchange of goods and...

. Competition is useful because it reveals actual customer demand and induces the seller (operator) to provide service quality levels and price levels that buyers (customers) want, typically subject to the seller’s financial need to cover its costs. In other words, competition can align the seller’s interests with the buyer’s interests and can cause the seller to reveal his true costs and other private information. In the absence of perfect competition, three basic approaches can be adopted to deal with problems related to the control of market power and an asymmetry between the government and the operator with respect to objectives and information: (a) subjecting the operator to competitive pressures, (b) gathering information on the operator and the market, and (c) applying incentive regulation.

Quick Reference to Basic Market Structures

Market Structure	Seller Entry Barriers	Seller Number	Buyer Entry Barriers	Buyer Number
Perfect Competition Perfect competition In economic theory, perfect competition describes markets such that no participants are large enough to have the market power to set the price of a homogeneous product. Because the conditions for perfect competition are strict, there are few if any perfectly competitive markets...	No	Many	No	Many
Monopolistic competition Monopolistic competition Monopolistic competition is imperfect competition where many competing producers sell products that are differentiated from one another...	No	Many	No	Many
Oligopoly Oligopoly An oligopoly is a market form in which a market or industry is dominated by a small number of sellers . The word is derived, by analogy with "monopoly", from the Greek ὀλίγοι "few" + πόλειν "to sell". Because there are few sellers, each oligopolist is likely to be aware of the actions of the others...	Yes	Few	No	Many
Oligopsony Oligopsony An oligopsony is a market form in which the number of buyers is small while the number of sellers in theory could be large. This typically happens in a market for inputs where numerous suppliers are competing to sell their product to a small number of buyers...	No	Many	Yes	Few
Monopoly Monopoly A monopoly exists when a specific person or enterprise is the only supplier of a particular commodity...	Yes	One	No	Many
Monopsony Monopsony In economics, a monopsony is a market form in which only one buyer faces many sellers. It is an example of imperfect competition, similar to a monopoly, in which only one seller faces many buyers...	No	Many	Yes	One

The correct sequence of the market structure from most to least competitive is perfect competition, imperfect competition, oligopoly, and pure monopoly.

The main criteria by which one can distinguish between different market structures are: the number and size of producers and consumer

Consumer

Consumer is a broad label for any individuals or households that use goods generated within the economy. The concept of a consumer occurs in different contexts, so that the usage and significance of the term may vary.-Economics and marketing:...

s in the market, the type of goods

Product (business)

In general, the product is defined as a "thing produced by labor or effort" or the "result of an act or a process", and stems from the verb produce, from the Latin prōdūce ' lead or bring forth'. Since 1575, the word "product" has referred to anything produced...

 and services being traded, and the degree to which information

Information

Information in its most restricted technical sense is a message or collection of messages that consists of an ordered sequence of symbols, or it is the meaning that can be interpreted from such a message or collection of messages. Information can be recorded or transmitted. It can be recorded as...

 can flow freely.

See also

• Economics
  Economics
  Economics is the social science that analyzes the production, distribution, and consumption of goods and services. The term economics comes from the Ancient Greek from + , hence "rules of the house"...
  
  
• Microeconomics
  Microeconomics
  Microeconomics is a branch of economics that studies the behavior of how the individual modern household and firms make decisions to allocate limited resources. Typically, it applies to markets where goods or services are being bought and sold...
  
  
• Macroeconomics
  Macroeconomics
  Macroeconomics is a branch of economics dealing with the performance, structure, behavior, and decision-making of the whole economy. This includes a national, regional, or global economy...
  
  
• Industrial organization
  Industrial organization
  Industrial organization is the field of economics that builds on the theory of the firm in examining the structure of, and boundaries between, firms and markets....
  
  
• Herfindahl index
  Herfindahl index
  The Herfindahl index is a measure of the size of firms in relation to the industry and an indicator of the amount of competition among them. Named after economists Orris C. Herfindahl and Albert O. Hirschman, it is an economic concept widely applied in competition law, antitrust and also...
  
  
• List of marketing topics
• List of management topics
• List of economics topics
• List of accounting topics
• List of finance topics

The market form can equally be known to an extent by the barriers on entry and exit.
It is to be noted that the Perfectly Competitive market, there exists free entry and exit; this applies to prospective/existing buyers and sellers. Though, this is not the case with the Imperfect market structure.

External links

• Microeconomics by Elmer G. Wiens: Online Interactive Models of Oligopoly, Differentiated Oligopoly, and Monopolistic Competition