Market concentrationIn economics, market concentration is a function of the number of firms and their respective shares of the total production (alternatively, total capacity or total reserves) in a market. Market concentration is the portion of a given market's market share that is held by a small number of businesses. To ascertain whether an industry is competitive or not, it is employed in antitrust law and economic regulation. When market concentration is high, it indicates that a few firms dominate the market and oligopoly or monopolistic competition is likely to exist.
Receptor antagonistA receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins. They are sometimes called blockers; examples include alpha blockers, beta blockers, and calcium channel blockers. In pharmacology, antagonists have affinity but no efficacy for their cognate receptors, and binding will disrupt the interaction and inhibit the function of an agonist or inverse agonist at receptors.
Postal codeA postal code (also known locally in various English-speaking countries throughout the world as a postcode, post code, PIN or ZIP Code) is a series of letters or digits or both, sometimes including spaces or punctuation, included in a postal address for the purpose of sorting mail. the Universal Postal Union lists 160 countries which require the use of a postal code. Although postal codes are usually assigned to geographical areas, special codes are sometimes assigned to individual addresses or to institutions that receive large volumes of mail, such as government agencies and large commercial companies.
Cost-effectiveness analysisCost-effectiveness analysis (CEA) is a form of economic analysis that compares the relative costs and outcomes (effects) of different courses of action. Cost-effectiveness analysis is distinct from cost–benefit analysis, which assigns a monetary value to the measure of effect. Cost-effectiveness analysis is often used in the field of health services, where it may be inappropriate to monetize health effect.
Competitive inhibitionCompetitive inhibition is interruption of a chemical pathway owing to one chemical substance inhibiting the effect of another by competing with it for binding or bonding. Any metabolic or chemical messenger system can potentially be affected by this principle, but several classes of competitive inhibition are especially important in biochemistry and medicine, including the competitive form of enzyme inhibition, the competitive form of receptor antagonism, the competitive form of antimetabolite activity, and the competitive form of poisoning (which can include any of the aforementioned types).
Financial marketA financial market is a market in which people trade financial securities and derivatives at low transaction costs. Some of the securities include stocks and bonds, raw materials and precious metals, which are known in the financial markets as commodities. The term "market" is sometimes used for what are more strictly exchanges, organizations that facilitate the trade in financial securities, e.g., a stock exchange or commodity exchange.
Competitive equilibriumCompetitive equilibrium (also called: Walrasian equilibrium) is a concept of economic equilibrium, introduced by Kenneth Arrow and Gérard Debreu in 1951, appropriate for the analysis of commodity markets with flexible prices and many traders, and serving as the benchmark of efficiency in economic analysis. It relies crucially on the assumption of a competitive environment where each trader decides upon a quantity that is so small compared to the total quantity traded in the market that their individual transactions have no influence on the prices.
Home videoHome video is recorded media sold or rented for home viewing. The term originates from the VHS and Betamax era, when the predominant medium was videotapes, but has carried over to optical disc formats such as DVD and Blu-ray. In a different usage, "home video" refers to amateur video recordings, also known as home movies. The home-video business distributes films, television series, telefilms and other audiovisual media in the form of videos in various formats to the public.
Postal censorshipPostal censorship is the inspection or examination of mail, most often by governments. It can include opening, reading and total or selective obliteration of letters and their contents, as well as covers, postcards, parcels and other postal packets. Postal censorship takes place primarily but not exclusively during wartime (even though the nation concerned may not be at war, e.g. Ireland during 1939–1945) and periods of unrest, and occasionally at other times, such as periods of civil disorder or of a state of emergency.
Budget constraintIn economics, a budget constraint represents all the combinations of goods and services that a consumer may purchase given current prices within his or her given income. Consumer theory uses the concepts of a budget constraint and a preference map as tools to examine the parameters of consumer choices . Both concepts have a ready graphical representation in the two-good case. The consumer can only purchase as much as their income will allow, hence they are constrained by their budget.
