Tugas Tulisan Bahasa Inggris bisnis 2

MARKET

A market is any one of a variety of systems, institutions, procedures, social relations and infrastructures whereby parties engage in exchange. While parties may exchange goods and services by barter, most markets rely on buyers offer their goods or services (including labor) in exchange for money (legal tender such as fiat money) from buyers.

For a market to be competitive, there must be more than a single buyer or seller. It has been suggested that two people may trade, but it takes at least three persons to have a market, so that there is competition on at least one of its two sides. However, competitive markets rely on much larger numbers of both buyers and sellers. A market with single seller and multiple buyers is a monopoly. A market with a single buyer and multiple sellers is a monopsony. These are the extremes of imperfect competition.

Markets vary in form, scale (volume and geographic reach), location, and types of participants, as well as the types of goods and services traded. Examples include:

• physical retail markets, such as local farmers' markets, which be held in town squares or parking lots on an ongoing or occasional basis, shopping centers and shopping malls
• (non-physical) internet markets (see electronic commerce)
• ad hoc auction markets
• markets for intermediate goods used in production of other goods and services
• labor markets
• international currency and commodity markets
• stock markets, for the exchange of shares in corporations
• artificial markets created by regulation to exchange rights for derivatives that have been designed to ameliorate externalities, such as pollution permits (see carbon trading)
• illegal markets such as the market for illicit drugs, arms or pirated products

In mainstream economics, the concept of a market is any structure that allows buyers and sellers to exchange any type of goods, services and information. The exchange of goods or services for money is a transaction. Market participants consist of all the buyers and sellers of a good who influence its price. This influence is a major study of economics and has given rise to several theories and models concerning the basic market forces of supply and demand. There are two roles in markets, buyers and sellers. The market facilitates trade and enables the distribution and allocation of resources in a society. Markets allow any tradable item to be evaluated and priced. A market emerges more or less spontaneously or is constructed deliberately by human interaction in order to enable the exchange of rights (cf. ownership) of services and goods.Historically, markets originated in physical marketplaces which would often develop into — or from — small communities, towns and cities.

Types of markets

Although many markets exist in the traditional sense — such as a marketplace — there are various other types of markets and various organizational structures to assist their functions. The nature of business transactions could define markets.

Financial markets

Financial markets facilitate the exchange of liquid assets. Most investors prefer investing in two markets, the stock markets and the bond markets. NYSE, AMEX, and the NASDAQ are the most common stock markets in the US. Futures markets, where contracts are exchanged regarding the future delivery of goods are often an outgrowth of general commodity markets.

Currency markets are used to trade one currency for another, and are often used for speculation on currency exchange rates.The money market is the name for the global market for lending and borrowing.

Prediction markets

Prediction markets are a type of speculative market in which the goods exchanged are futures on the occurrence of certain events. They apply the market dynamics to facilitate information aggregation.

Organization of markets

A market can be organized as an auction, as a private electronic market, as a commodity wholesale market, as a shopping center, as a complex institution such as a stock market, and as an informal discussion between two individuals.

Markets of varying types can spontaneously arise whenever a party has interest in a good or service that some other party can provide. Hence there can be a market for cigarettes in correctional facilities, another for chewing gum in a playground, and yet another for contracts for the future delivery of a commodity. There can be black markets, where a good is exchanged illegally and virtual markets, such as eBay, in which buyers and sellers do not physically interact during negotiation. There can also be markets for goods under a command economy despite pressure to repress them.

Mechanisms of markets

In economics, a market that runs under laissez-faire policies is a free market. It is "free" in the sense that the government makes no attempt to intervene through taxes, subsidies, minimum wages, price ceilings, etc. Market prices may be distorted by a seller or sellers with monopoly power, or a buyer with monopsony power. Such price distortions can have an adverse effect on market participant's welfare and reduce the efficiency of market outcomes. Also, the relative level of organization and negotiating power of buyers and sellers markedly affects the functioning of the market. Markets where price negotiations meet equilibrium though still do not arrive at desired outcomes for both sides are said to experience market failure.

Study of markets

The study of actual existing markets made up of persons interacting in space and place in diverse ways is widely seen as an antidote to abstract and all-encompassing concepts of “the market” and has historical precedent in the works of Fernand Braudel and Karl Polanyi. The latter term is now generally used in two ways. First, to denote the abstract mechanisms whereby supply and demand confront each other and deals are made. In its place, reference to markets reflects ordinary experience and the places, processes and institutions in which exchanges occurs. Second, the market is often used to signify an integrated, all-encompassing and cohesive capitalist world economy. A widespread trend in economic history and sociology is skeptical of the idea that it is possible to develop a theory to capture an essence or unifying thread to markets. For economic geographers, reference to regional, local, or commodity specific markets can serve to undermine assumptions of global integration, and highlight geographic variations in the structures, institutions, histories, path dependencies, forms of interaction and modes of self-understanding of agents in different spheres of market exchange. Reference to actual markets can show capitalism not as a totalizing force or completely encompassing mode of economic activity, but rather as "a set of economic practices scattered over a landscape, rather than a systemic concentration of power".

C. B. Macpherson identifies an underlying model of the market underlying Anglo-American liberal-democratic political economy and philosophy in the seventeenth and eighteenth centuries: Persons are cast as self-interested individuals, who enter into contractual relations with other such individuals, concerning the exchange of goods or personal capacities cast as commodities, with the motive of maximizing pecuniary interest. The state and its governance systems are cast as outside of this framework. This model came to dominant economic thinking in the later nineteenth century, as economists such as Ricardo, Mill, Jevons, Walras and later neo-classical economics shifted from reference to geographically located marketplaces to an abstract "market". This tradition is continued in contemporary neoliberalism, where the market is held up as optimal for wealth creation and human freedom, and the states’ role imagined as minimal, reduced to that of upholding and keeping stable property rights, contract, and money supply. This allowed for boilerplate economic and institutional restructuring under structural adjustment and post-Communist reconstruction.

Similar formalism occurs in a wide variety of social democratic and Marxist discourses that situate political action as antagonistic to the market. In particular, commodification theorists such as Georg Lukács insist that market relations necessarily lead to undue exploitation of labour and so need to be opposed in toto. Pierre Bourdieu has suggested the market model is becoming self-realizing, in virtue of its wide acceptance in national and international institutions through the 1990s. The formalist conception faces a number of insuperable difficulties, concerning the putatively global scope of the market to cover the entire Earth, in terms of penetration of particular economies, and in terms of whether particular claims about the subjects (individuals with pecuniary interest), objects (commodities), and modes of exchange (transactions) apply to any actually existing markets.

A central theme of empirical analyses is the variation and proliferation of types of markets since the rise of capitalism and global scale economies. The Regulation School stresses the ways in which developed capitalist countries have implemented varying degrees and types of environmental, economic, and social regulation, taxation and public spending, fiscal policy and government provisioning of goods, all of which have transformed markets in uneven and geographical varied ways and created a variety of mixed economies. Drawing on concepts of institutional variance and path dependency, varieties of capitalism theorists (such as Hall and Soskice) identify two dominant modes of economic ordering in the developed capitalist countries, "coordinated market economies" such as Germany and Japan, and an Anglo-American "liberal market economies". However, such approaches imply that the Anglo-American liberal market economies in fact operate in a matter close to the abstract notion of "the market". While Anglo-American countries have seen increasing introduction of neo-liberal forms of economic ordering, this has not lead to simple convergence, but rather a variety of hybrid institutional orderings. Rather, a variety of new markets have emerged, such as for carbon trading or rights to pollute. In some cases, such as emerging markets for water, different forms of privatization of different aspects of previously state run infrastructure have created hybrid private-public formations and graded degrees of commodification, commercialization and privatization.

Problematic for market formalism is the relationship between formal capitalist economic processes and a variety of alternative forms, ranging from semi-feudal and peasant economies widely operative in many developing economies, to informal markets, barter systems, worker cooperatives, or illegal trades that occur in most developed countries. Practices of incorporation of non-Western peoples into global markets in the nineteenth and twentieth century did not merely result in the quashing of former social economic institutions. Rather, various modes of articulation arose between transformed and hybridized local traditions and social practices and the emergence world economy. So called capitalist markets in fact include and depend on a wide range of geographically situated economic practices that do not follow the market model. Economies are thus hybrids of market and non-market elements.

Helpful here is J. K. Gibson-Graham’s complex topology of the diversity of contemporary market economies describing different types of transactions, labour, and economic agents. Transactions can occur in underground markets (such as for marijuana) or be artificially protected (such as for patents). They can cover the sale of public goods under privatization schemes to co-operative exchanges and occur under varying degrees of monopoly power and state regulation. Likewise, there are a wide variety of economic agents, which engage in different types of transactions on different terms: One cannot assume the practices of a religious kindergarten, multinational corporation, state enterprise, or community-based cooperative can be subsumed under the same logic of calculability. This emphasis on proliferation can also be contrasted with continuing scholarly attempts to show underlying cohesive and structural similarities to different markets.

A prominent entry point for challenging the market model's applicability concerns exchange transactions and the homo economicus assumption of self-interest maximization. There are now a number of streams of economic sociological analysis of markets focusing on the role of the social in transactions, and the ways transactions involve social networks and relations of trust, cooperation and other bonds. Economic geographers in turn draw attention to the ways in exchange transactions occur against the backdrop of institutional, social and geographic processes, including class relations, uneven development, and historically contingent path dependencies. A useful schema is provided by Michel Callon's concept of framing: Each economic act or transaction occurs against, incorporates and also re-performs a geographically and cultural specific complex of social histories, institutional arrangements, rules and connections. These network relations are simultaneously bracketed, so that persons and transactions may be disentangled from thick social bonds. The character of calculability is imposed upon agents as they come to work in markets and are "formatted" as calculative agencies. Market exchanges contain a history of struggle and contestation that produced actors predisposed to exchange under c An emerging theme worthy of further study is the interrelationship, interpenetrability and variations of concepts of persons, commodities, and modes of exchange under particular market formations. This is most pronounced in recent movement towards post-structuralist theorizing that draws on Foucault and Actor Network Theory and stress relational aspects of personhood, and dependence and integration into networks and practical systems. Commodity network approaches further both deconstruct and show alternatives to the market models concept of commodities. Here, both researchers and market actors are understood as reframing commodities in terms of processes and social and ecological relationships. Rather than a mere objectification of things traded, the complex network relationships of exchange in different markets calls on agents to alternatively deconstruct or “get with” the fetish of commodities. Gibson-Graham thus read a variety of alternative markets, for fair trade and organic foods, or those using Local Exchange Trading Systems as not only contributing to proliferation, but also forging new modes of ethical exchange and economic subjectivities.

Most markets are regulated by state wide laws and regulations. While barter markets exist, most markets use currency or some other form of money.Any investments made in markets should be carefully analyzed and read through before investing if the market crashes value of stock may go down leading to heavy losses

Size parameters

Market size can be given in terms of the number of buyers and sellers in a particular market or in terms of the total exchange of money in the market, generally annually (per year). When given in terms of money, market size is often termed market value, but in a distinguished sense than the market value of individual products. For one and the same goods, there may be different (and generally increasing) market values at the production level, the wholesale level and the retail level. For example, the value of the global illicit drug market for the year 2003 was estimated by the United Nations to be US$13 billion at the production level, $94 billion at the wholesale level (taking seizures into account), and US$322 billion at the retail level (based on retail prices and taking seizures and other losses into account).

Tugas Tulisan Bahasa Inggris bisnis 2

In economics, demand is the desire to own anything, the ability to pay for it, and the willingness to pay (see also supply and demand). The term demand signifies the ability or the willingness to buy a particular commodity at a given point of time.

Economists record demand on a demand schedule and plot it on a graph as a demand curve that is usually downward sloping. The downward slope reflects the relationship between price and quantity demanded: as price decreases, quantity demanded increases. In principle, each consumer has a demand curve for any product that he or she would consider buying, and the consumer's demand curve is equal to the marginal utility (benefit) curve. When the demand curves of all consumers are added up, the result is the market demand curve for that product. If there are no externalities, the market demand curve is also equal to the social utility (benefit) curve.

Elements of the Law of Demand As Melvin and Boyes note the law of demand is defined as:

1. The quantity of a well defined good or service that:
2. People are willing and able to buy.
3. During a particular period of time.
4. Decreases/increases as the price of that good or service rises/falls
5. All other factors remain constant.

Demand is a relationship between two variables, price and quantity demanded, with all other factors that could affect demand being held constant. 'well defined'- The key phrase in the first element is “well defined”. The purpose of the phrase is to ensure that we are examining the relationship between price and quantity demanded for the same good. If we are interested in demand for a particular good there is no reason to compare the relationship between the price of the good and the change in quantity demanded of a different goods. Goods are well defined if they share the same characteristics - brand, model, age, quality and performance to name a few. For example a Cadillac CTS-V is a high performance car manufactured by General Motors. The defining feature of the car is its engine a a supercharged OHV 6.2 liter L V-8. The engine produces 556 horsepower and 551 lb·ft of torque. The enables the to go from zero to 60 in 3.9 seconds. The car cost about 65,000.00. If we are interested in the demand for the CTS-V we need to compare the price of a CTS-V to the quantity demanded for a CTS-V and not a Ford Festiva.

willing and able - to participate in the market a consumer must not only be willing to buy a good she must be able to buy as well. For example, John may want to buy a Cadillac CTS. However unless he has the cash or credit to consummate the purchase his unrealized desires are irrelevant.

particular time period - demand measures the rate at which goods are being purchased during a specified period of time. For example to say that four thousand units are sold at a price of 65,000 does not tell us the level of demand unless we specify the time period per day per week per month.

nature of the relationship - this portion of the definition establishes that the price and quantity demanded have a negative or inverse relationship along the demand curve.

held constant ; there are innumerable factors other than price than can affect the level of demand. Some of the more important are income, price of related goods^[4], number of buyers, expectations and tastes and preferences.^[5] To focus on the cause and effect relationship between the good's own price and the quantity of the good demanded all these other factors must be held constant. To hold a variable constant means to freeze its value and not allow it to change.

Factors affecting demand

Innumerable factors and circumstances could affect a buyer's willingness or ability to buy a good. Some of the more common factors are:

Good's own price:The basic demand relationship is between potential prices of a good and the quantities that would be purchased at those prices. Generally the relationship is negative meaning that an increase in price will induce a decrease in the quantity demanded. This negative relationship is embodied in the downward slope of the consumer demand curve. The assumption of a negative relationship is reasonable and intuitive. If the price of a new novel is high, a person might decide to borrow the book from the public library rather than buy it. Or if the price of a new piece of equipment is high a firm may decide to repair existing equipment rather than replacing it.

Price of related goods: The principal related goods are complements and substitutes. A complement is a good that is used with the primary good. Examples include hotdogs and mustard, beer and pretzels, automobiles and gasoline. (Perfect complements behave as a single good.) If the price of the complement goes up the quantity demanded of the other good goes down. Mathematically, the variable representing the price of the complementary good would have a negative coefficient in the demand function. For example, Q_d = a - P - P_g where Q is the quantity of automobiles demanded, P is the price of automobiles and P_g is the price of gasoline. The other main category of related goods are substitutes. Substitutes are goods that can be used in place of the primary good. The mathematical relationship between the price of the substitute and the demand for the good in question is positive. If the price of the substitute goes down the demand for the good in question goes down.

Income: In most cases, the more income you have the more likely you buy.

Tastes or preferences:The greater the desire to own a good the more likely you are to buy the good. There is a basic distinction between desire and demand. Desire is a measure of the willingness to buy a good based on its intrinsic qualities. Demand is the willingness and ability to put one's desires into effect. It is assumed that tastes and preferences are relatively constant.

Consumer expectations about future prices and income: If a consumer believes that the price of the good will be higher in the future he is more likely to purchase the good now. If the consumer expects that her income will be higher in the future the consumer may buy the good now. In other words positive expectations about future income may encourage present consumption.

• This list is not exhaustive. All facts and circumstances that a buyer finds relevant to his willingness or ability to buy goods can affect demand. For example, a person caught in an unexpected storm is more likely to buy an umbrella than if the weather were bright and sunny.

Demand function and demand equation

The demand equation is the mathematical expression of the relationship between the quantity of a good demanded and those factors that affect the willingness and ability of a consumer to buy the good. For example, Q_d = f(P; P_rg, Y) is a demand equation where Q_d is the quantity of a good demanded, P is the price of the good, P_rg is the price of a related good, and Y is income; the function on the right side of the equation is called the demand function. The semi-colon in the list of arguments in the demand function means that the variables to the right are being held constant as we plot the demand curve in (quantity, price) space. A simple example of a demand equation is Q_d = 325 - P - 30P_rg + 1.4Y. Here 325 is the repository of all relevant non-specified factors that affect demand for the product. P is the price of the good. The coefficient is negative in accordance with the law of demand. The related good may be either a complement or a substitute. If a complement, the coefficient of its price would be negative as in this example. If a substitute, the coefficient of its price would be positive. Income, Y, has a positive coefficient indicating that the good is a normal good. If the coefficient was negative the good in question would be an inferior good meaning that the demand for the good would fall as the consumer's income increased. Specifying values for the non price determinants, Prg = 4.00 and Y = 50, results in the demand equation Q = 325 - P - 30(4) +1.4(50) or Q = 275 - P. If income were to increase to 55 the new demand equation would be Q = 282 - P. Graphically this change in a non price determinant of demand would be reflected in an outward shift of the demand function caused by a change in the x intercept.

Demand curve

Demand curve The relationship of price and quantity demanded can be exhibited graphically as the demand curve. The curve is generally negatively sloped. The curve is two-dimensional and depicts the relationship between two variables only: price and quantity demanded. All other factors affecting demand are held constant. However, these factors are part of the demand curve and influence the location of the curve. In many economics graphs, such as that of the demand curve, the independent variable is plotted on the vertical axis and the dependent variable on the horizontal axis. Consequently, the graphical presentation is technically that of the equation P = f(Q) where f(Q) is the inverse demand function, although the graph is referred to simply as the demand curve.

Income and Substitution Effects

The negative slope of the demand curve is due to the substitution and income effects. If the relative price of a good falls consumers will substitute that good for more expensive goods -that will buy more of the good whose relative price has fallen and less of the other goods. This is the substitution effect. When the relative price of a good falls the consumer can buy the same bundle of goods as before the price decline and have some money left over. This money can be used to purchase more of all his consumption goods. In other words his purchasing power is called the income effect.

Discrete goods

In some cases it is impractical to represent the relationship between price and demand with a continuous curve because of small quantities demanded. Goods and services measured in small units are best represented with a smooth curve. Examples include food measured in calories and leisure measured in minutes. However, when the price of a good is very high in proportion to a consumer's budget there is a need to incorporate this limitation in both the mathematical analysis and the graph representing the relationship. While cars and houses are discrete goods for most people, cheaper goods such as glasses and bicycles are discrete goods only for the very poor. On the national level, nuclear power plants or space stations may be considered discrete goods. The concept is more useful at the individual consumer's level than at the consumers' aggregate level, because for example the difference between 3,000,000 cars demanded and 3,000,001 cars demanded is so little that the market demand for cars can be viewed as essentially continuous.

The demand curve in the discrete case

The price where the consumer is indifferent between buying an extra unit and not buying an extra unit is called the reservation price (r) after the same term used in auctions. If p is the price of the good and n units of the good are demanded, then r_n>=p>=r_n+1. For example, John is considering whether to buy a car or not (n=0 or n=1). The price of the car is $15,000 (p=15,000). The determining factor in John's consumption choice is his reservation price, r, simply the maximum price he is willing to pay for the car, reflecting his preferences. If John purchases this car and only this car then r₁>=15,000>=r₂ but if he does not purchase the car then r₀>=15,000>=r₁.

As with other demand curves, discrete demand curves are usually downward sloping, but in the case of discrete goods the curve is shaped like a staircase, reflecting the properties of goods which can only be consumed in quantities of integers. The horizontal line segments represent prices at which the consumer is indifferent between buying an extra unit or not. The vertical line segments represent ranges of prices where the quantity demanded does not vary. Nevertheless, as prices change within these ranges, the consumer surplus may change.

Movements versus shifts

The demand curve is a two-dimensional depiction of the relationship between price and quantity demanded. Movements along the curve occur only if there is a change in quantity demanded caused by a change in the good's own price. A shift in the demand curve, referred to as a change in demand, occurs only if a non-price determinant of demand changes. For example, if the price of a complement were to increase, the demand curve would shift leftward reflecting a decrease in demand. The shifted demand curve represents a new demand equation.

Movement along a demand curve due to a change in the good's price results in a change in the quantity demanded, not a change in demand. A change in demand refers to a shift in the position of the demand curve in two-dimensional space resulting from a change in one of the other arguments of the demand function.

From individual to market demand curve

The market demand curve is the horizontal summation of individual consumer demand curves. Aggregation introduces three additional non-price determinants of demand: (1) the number of consumers; (2) "the distribution of tastes among the consumers"; and (3) "the distribution of incomes among consumers of different taste." Thus if the population of consumers increases, ceteris paribus the market demand curve will shift outward (to the right). If the proportion of consumers with a strong preference for a good increases, ceteris paribus the demand for the good will increase. Finally if the distribution of income changes is favor of those consumers with a strong preference for the good in question the demand will shift out. Factors that affect individual demand can also affect market demand. However, net effects must be considered. For example, a good that is a complement for one person is not necessarily a complement for another; Further, the strength of the relationship would vary among persons. So in the aggregate the goods might be substitutes or complements. Finally the demand for a firm's product or services will often depend on such factors as competitors prices and marketing strategies.

Determinants of PED

The overriding factor in determining PED is the willingness and ability of consumers after a price changes to postpone immediate consumption decisions concerning the good and to search for substitutes (wait and look). The greater the incentive the consumer has to delay consumption and search for substitutes and the more readily available substitutes are the more elastic the demand will be. Specific factors are:

Availability of substitutes: The more choices that are available, the more elastic is the demand for a good. If the price of Pepsi goes up by 20%, one can always purchase Coke, 7-Up, Dr. Pepper and so forth. One's willingness and ability to postpone the consumption of Pepsi and get by with a "lesser brand" makes the PED of Pepsi relatively elastic.

Necessity: With a true necessity a consumer has neither the willingness nor the ability to postpone consumption. There are few or no satisfactory substitutes. Insulin is the ultimate necessity, so the demand for it is inelastic.

Importance is terms of proportion of income spent on a good: Most consumers have both the willingness and ability to postpone the purchase of big ticket items. If an item constitutes a significant portion of one's income, it is worth one's time to search for substitutes. A consumer will give more time and thought to the purchase of a $3000 television than a $1 candy bar, so demand for the former will be more elastic than demand for the latter.

Duration: The more time a consumer has to search for substitute goods, the more elastic the demand.

Breadth of definition: how specifically the good is defined. For example, the demand for automobiles is less elastic than the demand for Toyotas, which is in turn less elastic than the demand for Red Toyota Priuses.

Availability of information concerning substitute goods: The easier it is for a consumer to locate the substitute goods, the more willing he will be to undertake the search, and the more elastic demand will be.

Elasticity along linear demand curve

The slope of a linear demand curve is constant. The elasticity of demand changes continuously as one moves down the demand curve because the ratio of price to quantity continuosly falls. At the point the demand curve intersects the y-axis PED is infinitely elastic, because the variable Q apperaing in the demominator of the elasticity formula is zero there. At the point the demand curve intersects the x-axis PED is zero, because the variable P appearing in the numerator of the elasticity formula is zero there. At one point on the demand curve PED is unitary elastic: PED equals one. Above the point of unitary elasticity is the elastic range of the demand curve (meaning that the elasticity is greater than one). Below is the inelastic range, in which the elasticity is less than one. The decline in elasticity as one moves down the curve is due to the falling P/Q ratio.

Market structure and the demand curve

In perfectly competitive markets the demand curve, the average revenue curve, and the marginal revenue curve all coincide and are horizontal at the market-given price. The demand curve is perfectly elastic and coincides with the average and marginal revenue curves. Economic actors are price-takers. Perfectly competitive firms have zero market power; that is, they have no ability to affect the terms and conditions of exchange. A perfectly competitive firm's decisions are limited to whether to produce and if so, how much. In less than perfectly competitive markets the demand curve is negatively sloped and there is a separate marginal revenue curve. A firm in a less than perfectly competitive market is a price-setter. The firm can decide how much to produce or what price to charge. In deciding one variable the firm is necessarily determining the other variable.

Inverse demand function

In its standard form a linear demand equation is Q = a - bP. That is, quantity demanded is a function of price. The inverse demand equation, or price equation, treats price as a function g of quantity demanded: P = f(Q). To compute the inverse demand equation, simply solve for P from the demand equation. For example, if the demand equation is Q = 240 - 2P then the inverse demand equation would be P = 120 - .5Q, the right side of which is the inverse demand function.

The inverse demand function is useful in deriving the total and marginal revenue functions. Total revenue equals price, P, times quantity, Q, or TR = P×Q. Multiply the inverse demand function by Q to derive the total revenue function: TR = (120 - .5Q) × Q = 120Q - 0.5Q². The marginal revenue function is the first derivative of the total revenue function; here MR = 120 - Q. Note that the MR function has the same y-intercept as the inverse demand function in this linear example; the x-intercept of the MR function is one-half the value of that of the demand function, and the slope of the MR function is twice that of the inverse demand function. This relationship holds true for all linear demand equations. The importance of being able to quickly calculate MR is that the profit-maximizing condition for firms regardless of market structure is to produce where marginal revenue equals marginal cost (MC). To derive MC the first derivative of the total cost function is taken. For example assume cost, C, equals 420 + 60Q + Q². Then MC = 60 + 2Q. Equating MR to MC and solving for Q gives Q = 20. So 20 is the profit maximizing quantity: to find the profit-maximizing price simply plug the value of Q into the inverse demand equation and solve for P.

Residual demand curve

The demand curve facing a particular firm is called the residual demand curve. The residual demand curve is the market demand that is not met by other firms in the industry at a given price. The residual demand curve is the market demand curve D(p), minus the supply of other organizations, So(p): Dr(p) = D(p) - So(p )