Chapter 1: What is Economics? Definition of Economics What we can get as a society is limited by our productive resources such as the gifts of nature, human labor and ingenuity, tools and equipment that we have produced. Scarcity: Our inability to satisfy all our wants. Faced with scarcity, we must choose among the available alternatives. E.g. The child must choose between the pop or the gum. However, the choices that we make depend on the incentives. Incentive: A reward that encourages an action or a penalty that discourages one. E.g. If the price of pop falls, the child has an incentive to choose more pop. Economics: Social science that studies the choices that individuals, businesses, governments, and entire societies make as they cope with scarcity and the incentives that influence and reconcile those choices. Economics is divided into two main parts: Microeconomics and Macroeconomics. Microeconomics: The study of the choices that individuals and businesses make, the way these choices interact in markets, and the influence of governments. E.g. How would a tax on e commerce affect eBay? Macroeconomics: The study of the performance of the national economy and the global economy. E.g. Why did inflation in Canada start to increase in 2008? Two Big Economic Questions Two big questions summarize the scope of economics: 1. How do choices end up determining what, how, and for whom goods and services are produced? What: What goods/services do we produce? How: How do we use the factors of production to produce these goods? For Whom: Who consumes the goods/services that are produced? 2. How can choices made in the pursuit of selfinterest also promote the social interest? Goods and services are produced by using productive resources that economists call factors of production.
1. Land: Natural resources. (Minerals, oil, gas, coal, water, forests, fish.) 2. Labor: Physical and mental efforts of peoples work/time. The quality of labor depends on human capital (knowledge and skill that people obtain from education, onthejob training, work experience). 3. Capital: Tools, instruments, machines, buildings and other constructions that businesses use to produce goods and services. (Money, stocks, bonds, are financial capital.) 4. Entrepreneurship: Human Resource that organizes the first 3 factors. People earn their incomes by selling the services of the factors of production they own: 1. Land earns rent, 2. Labor earns wages, 3. Capital earns interest, 4. Entrepreneurship earns profit. Labor earns the most income. (70%. The other 3 share the rest.) Selfinterested choices promote the social interest if they lead to an outcome that is the best for society as a whole by using resources efficiently and distributing goods and services equitably among individuals. Economists assume that incentives are key in reconciling selfinterest and the social interest. Human nature cannot change. Five topics that illustrate the 2 nd big economic question: Globalization, informationage economy, global warming, natural resource depletion, economic instability. The Economic Way of Thinking Buying power can be redistributed/transferred from one person to another in 3 ways: 1. Voluntary payments, 2. Theft, 3. Taxes and benefits organized by the gov. The Big Tradeoff: Tradeoff between equality and efficiency. (E.g. Taxing the rich and making transfers to the poor. Opportunity Cost: The opportunity cost of something is the highestvalued alternative that we must give up to get it. (E.g. The opportunity cost of a movie ticket is the number of coffee forgone.) Marginal Benefit: Additional benefit. E.g. Having a 3.0 but studying an extra night to raise GPA to 3.5. The marginal benefit is the extra 0.5 Marginal Cost: Additional Cost. E.g. The extra night spent studying is the marginal cost. Rational Choice: A rational choice is one that compares costs and benefits, and achieves the greatest benefit over cost for the person making the choice. Economics as Social Science and Policy Tool
Positive Statement: Could be right or wrong, but can be tested. It is about what is . Normative Statement: Expresses an opinion that cannot be tested. It is about what ought to be . Economic Model: Description of some aspect of the economic world that includes only those features that are needed for the purpose at hand. (E.g. Economic model of a cell phone: Prices of calls, number of users. Not used: Colors, ringtones). An economic model is simpler than the reality it describes. A model is tested by comparing its predictions with the facts. This is hard to do, so economists use natural experiments, statistical investigations, and economic experiments, to help. Natural Experiment: Situation in economic life where one factor of interest is diff and other things are equal or similar. E.g. Comparing Canada and the U.S. due to Canada having higher unemployment benefits but the people in both countries are similar. Statistical Investigation: Looks for correlation (a tendency for the values of two variables to move together, either in the same direction or in opposite directions) in a predictable and related way. E.g. Cigarette smoking and lung cancer are correlated. Economic Experiment: Puts people in a decisionmaking situation and varies the influence of one factor at a time to discover how they respond. The main economics policy tool is to compare/evaluate marginal benefits and marginal costs. To find greatest gain. It is useful for personal, business, and government policy.
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Production Possibilities and Opportunity Cost Production Possibilities Frontier (PPF): Boundary between those combinations of goods and services that can be produced and those that cannot. Points inside the PPF or on the PPF are attainable. However, points outside the PPF are production inefficient bcus resources are unused or misallocated, as opposed to points on the PPF which are production efficient where we can produce at the lowest possible cost. Points outside the PPF are unattainable. Opportunity Cost is a Ratio: It is the decrease in the quantity produced of one good divided by the increase in the quantity produced of another good as we move along the PPF. Because opportunity cost is a ratio, the opportunity cost of producing an additional can of cola is equal to the inverse of the opportunity cost of producing an additional pizza. Discrimination causes underemployment of resources. Women not allow to produce up to full abilities. (The point would be inside the PPF). If discrimination disappeared, than the point inside would go towards the point on the PPF. PPFs are generally outwardbowed (concave) shaped, and reflect increasing opportunity cost and resources that are not equally productive in all activities. By moving between two points on the PPF, more good X can be obtained only by producing less good Y. If no opportunity cost happens, then goods are being produced inside the PPF. There is no opportunity cost in moving from a point inside the PPF to a point on the PPF. Opportunity Cost Formula: quantity of goods you must give up quantity of goods you will get Using Resources Efficiently Allocative Efficiency: Only 1 point on the PPF that achieves the best production efficiency with the lowest cost and greatest benefit, and where marginal benefit=marginal cost. Marginal cost of a good can be calculated from the slope of the PPF. It is the opportunity cost of producing one more unit of that good. Marginal cost curve slops upwards bcus of increasing opportunity cost. Marginal benefit curve slopes downwards bcus of decreasing marginal benefit. Benefits apply to consumers only. To describe preferences, economists use the concept of marginal benefit. To illustrate preferences, economists use the marginal benefit curve.
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Principle of Decreasing Marginal Benefit: The more we have of a good/service, the smaller is its marginal benefit, and the less we are wiling to pay for an additional unit of it. When the PPF is a straight line (linear), it means constant opportunity and marginal costs. (Does not increase, but stays constant) Economic Growth Capital accumulation (including human capital), changes in resources such as its quantity, or technological change shifts the PPF outward, called economic growth, and expands production possibilities. The decrease in today’s consumption is the opportunity cost of tomorrow’s increase in consumption. To expand production possibilities in the future, a nation must devote fewer resources to producing consumption goods/services, and some resources to accumulating capital and developing new technologies. Gains from Trade Specialization: Producing only one good or a few goods. Specialization and exchange allow consumption (not production) at points outside the PPF. Comparative Advantage: A person has a comparative advantage if he/she can produce/perform at a lower opportunity cost than anyone else. The resources and technologies available determine the comparative advantages someone will have. Absolute Advantage: A person has an absolute advantage if he/she is more productive than another person in a large number of activities by using the same quantity of resources. Comparative advantage compares opportunity cost. Absolute advantage compares productivities (production per hour). A person who has an absolute advantage does not have a comparative advantage in every activity. Dynamic Comparative Advantage: A person has a dynamic comparative advantage when they have specialized in an activity by learningbydoing and, became the lowestcost producer. Economic Coordination Gains from trade and specialization require an economic coordination system. Two systems have been used:
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1. Central economic planning (rarely used anymore: Russia, China), 2. Decentralized markets In order for decentralized markets to work, 4 complementary social institutions are needed: (All of these are prerequisites to specialize and exchange) 1. Firms: Hire and organize factors of production to produce and sell goods/services. Coordinate much economic activity. Firms cannot get too big or produce all of their own goods. It is more efficient to specialize and trade with each other. 2. Markets: Coordinates buying/selling decisions through price adjustments. 3. Property Rights: Governing ownership, use, and disposal of recourses, goods/services. 4. Money: Any commodity or token acceptable as a mean of payment. E.g. Exchange of smoothies and salads between Joe and Liz. Circular Flows in the Market Economy: (Results from the choices that households and firms make.) Factors Market: (Red flow) 1. Households: Specialize and choose the quantities of labor, land, capital, entrepreneurial services to sell or rent to firms. 2. Firms: Choose the quantities of factors of production to hire. Goods Market: (Red flow) 1. Households: Choose the quantities of goods/services to buy. 2. Firms: Choose the quantities of goods/services to produce. Green flow: Households receive incomes and make expenditures on goods/services.
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Chapter 3: Demand and Supply Markets and Prices Competitive Market: A market with many buyers/sellers, so no one can influence the price. Money Price: Price of an object in numbers of dollars that must be given up in exchange for it. Relative Price: Ratio of the price of one good/service to the price of another good/service. A relative price is an opportunity cost. E.g. Money price of coffee is $2 a cup, money price of gum is $1 a pack. Formula of opportunity cost: price of 1 cup of coffee/price of 1 pack of gum . The opportunity cost and ratio of 1 cup of coffee is 2 packs of gum. Demand Quantity Demanded: Amount of a good/service that consumers plan to buy during a given time period at a particular price. Quantity demanded is not necessarily the same as the quantity actually bought. Sometimes the quantity demanded exceeds the amount of goods available, so the quantity bought is less than the quantity demanded. The Law of Demand: Other things remaining the same, the higher the price of a good, the smaller is the quantity demanded; and the lower the price of a good, the greater is the quantity demanded. Higher prices lowers demand due to substitution effect and income effect. Demand Curve: Represents the inverse relationship between quantity demanded and price. It is also a willingnessandabilitytopay curve which measures marginal benefit. Change in Quantity Demanded: Caused by a change in price which results in movement along the demand curve. Decrease in qu. demanded moves the curve up due to price rise, increase in qu. demanded moves the curve down due to price fall. Change in Demand: Caused by any other factor then the price which results in a shift of the demand curve. When demand increases, the demand curve shifts rightward, and the quantity demanded at each price is greater. If demand decreases, curve shifts leftward. 6 factors shift the demand curve: 1. Prices of related (substitute) goods, 2. Expected future prices, 3. Income, 4. Expected future income and credit, 5. Population, 6. Preferences. The demand curve shifts rightward if: (demand increases) 1. Price of a substitute rises, 2. Price of a complement falls, 3. Expected future price of the good rises, 4. Income increases (for a normal good), 5. Expected future income or credit increases, 6. Population increases.
Chapter 3: Demand and Supply The demand curve shifts leftward if: (demand decreases) 1. Price of a substitute falls, 2. Price of a complement rises, 3. Expected future price of the good falls, 4. Income decreases (for a normal good), 5.Expected future income or credit decrease, 6. Population decreases. Change in quantity demanded brings a movement on the demand curve. Change in demand shifts the demand curve right or left. Supply Quantity Supplied: Amount that producers plan to sell during a given time period at a particular price. The quantity supplied is not necessarily the same amount as the quantity actually sold. Sometimes the quantity supplied is greater than the quantity demanded, so the quantity sold is less than the quantity supplied. The Law of Supply: Other things remaining the same, the higher the price of a good, the greater is the quantity supplied; and the lower the price of a good, the smaller is the quantity supplied. Higher prices increase quantity supplied because marginal cost increases. Price must rise for producers to be willing to increase production and incur higher marginal cost. Supply Curve: Represents the positive relationship between quantity supplied and price. It is also a minimumsupplyprice curve, which shows the lowest price at which someone is willing to sell another unit. This lowest price is the marginal cost. Change in the Quantity Supplied: Caused by a change in price resulting in movement along the supply curve. Change in Supply: Caused by any other factor then the price which results in a shift of the supply curve. 6 main factors bring change in supply: 1. Price of factors of production, 2. Price of related goods produced, 3. Expected future prices, 4. Number of suppliers, 5. Technology, 6. State of nature (weather, environment). The supply curve shifts rightward if: (supply increases) 1. Prices of factors of production decreases, 2. Price of a complement in production increases, 3. Price of a substitute in production decreases, 4. Expected future prices decreases, 5. Number of suppliers increases, 6. Technology increases, 7. State of nature increases. The supply curve shifts leftward if: (supply decreases)
Chapter 3: Demand and Supply 1. Prices of factors of production increases, 2. Price of a complement in production decreases, 3. Price of a substitute in production increases, 4. Expected future prices increases, 5. Number of suppliers decreases, 6. Technology decreases, 7. State of nature decreases. For complements in production, higher price for one good will cause increased quantity for the other good as well. Change in quantity supplied brings a movement on the demand curve Change in supply shifts the demand curve right or left. Market Equilibrium Equilibrium Price: Price at which the quantity demanded equals quantity supplied. Equilibrium Quantity: Quantity bought and sold at the equilibrium price. Above the equilibrium price, there is a surplus, and price will fall. Below the equilibrium price, there is a shortage, and price will rise.
Chapter 4: Elasticity Elasticity is the measurement of how changing one economic variable affects others. Price Elasticity of Demand Price Elasticity of Demand: Measures responsiveness of quantity demanded to change in price. Formula to calculate the price elasticity of demand: E.g. Original point: $20.50 and 9 pizzas, New point: $19.50 and 11 pizzas. Change in price between $20.50 to $19.50: price falls by $1, and the average price is $20. So you do ($1/$20) x 100 = 5% Change in qu. demanded between 9 pizzas and 11 pizzas: Demand rises by 2 pizzas, and average demand is 10 pizzas. So you do (2/10) x 100 = 20% Price elasticity of demand: Percentage change in quantity demanded = 20% = 4 Percentage change in price 5%
Elasticity is the ratio of two percentage changes. A positive change in price brings a negative change in the quantity demanded, and therefore the price elasticity of demand is a negative number.
Chapter 4: Elasticity It is the magnitude or absolute value of the price elasticity of demand that tells us how responsive the quantity demanded is. To compare price elasticity of demand, we use the magnitude of the elasticity and ignore the minus sign. 5 types of elasticity demand curves: 1. Perfectly inelastic demand (vertical): Quantity demanded is constant regardless of the price. The price elasticity of demand is zero. E.g. Insulin for diabetics.
2. Inelastic demand: The percentage change in the qu. demanded is less than the percentage change in the price. The price elasticity of demand is between zero and 1. E.g. Food and shelters. 3. Unit elastic demand: The percentage change in the quantity demand equals the percentage change in the price. The price elasticity of demand is 1.
Chapter 4: Elasticity
4. Perfectly elastic demand (horizontal): The quantity demanded changes by an infinitely large percentage in respond to a tiny price change. The price elasticity of demand is infinity. E.g. Two soft drink machines located right beside each other with the same prices. People will buy equally from both machines. They are both the perfect substitutes.
Chapter 4: Elasticity 5. Elastic demand: The percentage change in the quantity demanded is less than the percentage change in the price. The price elasticity of demand is between zero and 1. E.g. Automobiles and furniture. Elasticity along a straightline demand curve:
On a straightline demand curve, elasticity decreases as the price falls, and the quantity demanded increases. Demand is unit elastic at the midpoint, elasticity is at 1. Above the midpoint, demand is elastic, below the midpoint, demand is inelastic. Total revenue: price of good x quantity sold. (P x Q) A change in the price changes the total revenue. But a rise in the price does not always increase total revenue. It depends on the elastic of demand: 1. If demand is elastic: A 1 percent price cut increases the qu. sold by more than 1 percent and total revenue increases. 2. If demand is inelastic: A 1 percent price cut increases the qu. sold by less than 1 percent and total revenue decreases. 3. If demand is unit elastic: A 1 percent price cut increases the qu. sold by 1 percent and total revenue does not change.
Chapter 4: Elasticity Total Revenue Test: Method of estimating the price elasticity of demand by observing the change in total revenue that results from a change in the price, when all other influences on the quantity sold remain the same. Your expenditure and your elasticity: 1. If your demand is elastic: A 1 percent price cut increase the qu. you buy by more than 1 percent, and your expenditure on the item increases. 2. If your demand is inelastic: A 1 percent price cut increases the qu. you buy by less than 1 percent, and your expenditure on the item decreases. 3. If your demand is unit elastic: A 1 percent price cut increases the qu. you buy by 1 percent and your expenditure on the item does not change. Summary: If you spend more on an item when its price falls your demand for that item is elastic. If you spend the same amount your demand is unit elastic, and if your spend less, your demand is inelastic. The elasticity of demand for a good depends on: 1. The closeness of substitutes: The closer the substitutes for a good/service, the more elastic is the demand. E.g. Oil which makes gasoline has substitutes such as electric cars, but not very close to gasoline, so the demand for oil is inelastic. Plastics are close substitutes for metals, so the demand for metals is elastic. Goods defined more narrowly have higher elasticity. E.g. A personal computer has no really close substitutes, but a Dell PC is a close substitute for a HewlettPackard PC. So the elasticity of demand for personal computers is lower than the elasticity of demand for a Dell or HP. Necessities generally have poor substitutes and inelastic demands, and luxuries generally have many substitutes and elastic demands. 2. The proportion of income spent on the good: The greater the proportion of income spent on the good, the more elastic is the demand for it. 3. The time elapsed since price change: The longer the time has elapsed since a price change, the more elastic is demand. Shortrun demand describes responsiveness to a change in price before sufficient time for all substitutions to be made. Longrun demand describes responsiveness to a change in price after sufficient time for all substitutions to be made. Shortrun demand is usually less elastic than longrun demand. More Elasticities of Demand
Chapter 4: Elasticity Cross Elasticity of Demand: Measure of the responsiveness of the demand for a good to a change in the price of a substitute or complement, other things remaining the same. Formula of cross elasticity of demand: percentage change in quantity demanded percentage change in price of a substitute or complement The cross elasticity of demand can be positive or negative. It is positive for a substitute (curve shifts rightward) and negative for a complement (curve shifts leftward). E.g. Original qu. of pizzas: 9 pizzas/h. New qu. of pizzas: 11 pizzas/h. So it’s a rise of +2 pizzas. And the average qu. is 10 pizzas. (+2/10) x 100 = +20% Original price of a burger: $1.50. New price of a burger: $2.50. (A burger is a substitute for pizza). So it’s a rise of $1 per burger. And the average price is $2 a burger. (+$1/$2) x 1000 = +50% Final answer using formula: +20% = 0.4 +50% If two items are close substitutes such as two brands of spring water, the cross elasticity is large. If two items are close complements such as movies and popcorn, the cross elasticity is large. If two items are somewhat unrelated to each other, such as newspapers and orange juice, the cross elasticity is small—perhaps even zero. Income Elasticity of Demand: Measure of the responsiveness of the demand for a good or service to a change in income, other things remaining the same. Formula to calculate elasticity of demand: percentage change in qu. demanded percentage change in income Income elasticities can be positive or negative. They fall into 3 ranges: 1. Greater than 1 (normal good, income elastic) 2. Positive and less than 1 (normal good, income inelastic) – Quantity demanded 3. Negative (inferior good) E.g. For income elastic demand – normal good. Income is $975/week, and 9 pizzas/h are bought. Income changes to $1,025/week, and 11 pizzas/h are bought. The change in the qu. demanded is +2 pizzas. The average qu. is 10 pizzas: (+2/10) x 100 = 20%. The change in income is +$50, and the average income is $1000: (+ $50/$1000) x 100 = 5% Using formula: 20% = 4 5%
Chapter 4: Elasticity The demand for pizza is income elastic. (because percentage increase in the qu. of pizza demanded exceeds the percentage increase in income.) Elasticity of Supply Elasticity of supply: Measures responsiveness of quantity supplied to change in price. Formula to calculate the elasticity of supply: percentage in change of quantity supplied percentage in change in price The Factors That Influence the Elasticity of Supply (1) Resource Substitution Possibilities: Goods/services produced only by using unique or rare productive resources have low, perhaps even a zero elasticity of supply. E.g. Van Gogh painting has a vertical supply curve and a zero elasticity of supply. Goods/services produced by using commonly available resources that could be allocated to a wide variety of alternative tasks have a high elasticity of supply. E.g. Wheat can be grown on land where corn can be grown as well, so it is just as easy to grow wheat as corn. The supply curve is almost horizontal and its elasticity of supply is very large. A good produced in many diff countries such as sugar and beef, the supply of good is highly elastic. The supply of most goods/services lies between these 2 extremes. (2) Time Frame for the Supply Decision: To study the influence of the amount of time elapsed since a price change, there are 3 time frames of supply: 1. Momentary supply When the price of a good rises or falls, the momentary supply curve shows the response of the quantity supplied immediately following the price change. E.g. Fruits have perfectly inelastic momentary supply curve vertical. Farmers ship however many oranges they have for that day to the market. No matter the price of oranges, producers cannot change their output. E.g. In contrast, long distance phone calls have perfectly elastic momentary supply, because when a great number of ppl use it at the same time, there is a big surge in the demand, but the price remains constant. They company makes sure that quantity supplied equals quantity demanded. 2. Longrun Supply
Chapter 4: Elasticity The longrun supply curve shows the response of the quantity supplied to a price change after all the technologically possible ways of adjusting supply have been exploited. E.g. For oranges, the long run is the time it takes new plantings to grow to full maturity – 15 years. In some cases, the longrun adjustment occurs only after a completely new production plant as been built and workers have been trained to operate it, which might take several years. 3. The Shortrun Supply The shortrun supply curve shows how the quantity supplied responds to a price change when only some of the technologically possible adjustments to production have been made. The shortrun supply curve slopes upward bcus producers can take actions quite quickly to change the qu. supplied in response to a price change. E.g. If the price of oranges fall, growers can stop picking ad leave oranges to tor on the trees. If the price rises, they can use more fertilizer to increase the yields of their existing trees.
Chapter 5: Efficiency and Equity Resource Allocation Methods Resources are scare, so they must be allocated somehow. Trading in markets is just one of several alternative methods. Resources might be allocated by the following 8 methods: (1) Market Price Resources go to those most willing and able to pay. (2) Command System Allocates resources by the order of someone in authority. E.g. Your labor at work is allocated to specific tasks by a command (your boss). Works best in organizations in which the lines of authority are clear. Works badly when the range of activities to be monitored are large. (3) Majority Rule Allocates resources in the way that a majority of voters choose. E.g. Societies use majority rule to elect representative governments that make some of the biggest decisions. (4) Contest Allocates resources to a winner (or a group of winners). E.g. Sporting events. The total output produced by the workers is much greater than it would be without the contest. (5) FirstCome, FirstServed Allocates resources to those who are first in line. (6) Lottery Allocates resources to those who pick the winning number, draw the lucky cards, or come up lucky in some other gaming system.
Chapter 5: Efficiency and Equity E.g. The purchase of tickets on eBay. Lotteries work best when there is no effective way to distinguish among potential users of scare resource. (7) Personal Characteristics Resources are allocated on the basis of personal characteristics, such as resources that matter the most to you. E.g. Choosing a marriage partner on the basis of personal characteristics, or allocating the best jobs to white males and discriminating against visible minorities and women which is unacceptable. (8) Force Plays a crucial role, both good and ill. Ill force is used for war with the use of military force by one nation against another. Or European settlers in the Americas and Australia. Theft in largescale and smallscale. Good force is transferring wealth from the rich to the poor. Demand and Marginal Benefit Resources are allocated efficiently when they are used in the way that people value most highly. This outcome occurs when marginal benefit = marginal cost. Demand, Willingness to Pay, and Value: Value is what consumers are willing to pay. Price is what consumers actually pay. The value of one more unit of a good/service is its marginal benefit. And we measure marginal benefit by the max price that is willingly paid for another unit of the good/service. Willingness to pay determines demand. A demand curve is a marginal benefit curve.
Chapter 5: Efficiency and Equity Individual Demand and Market Demand Individual demand: Relationship between the price of a good and the quantity demanded by one person. Market demand: Relationship between the price of a good and the quantity demanded by all buyers. The market demand curve is the horizontal sum of the individual demand curves and is formed by adding the quantities demanded by all the individuals at each price. E.g. At a price of $1 a slice, Lisa demands 30 slices, while Nick demands 10 slices. So the market quantity demanded at $1 Is 40 slices. From the market demand curve, we see that the economy is willing to pay $1 for 40 slices a day.
The market demand curve is the marginal social benefit (MSB) curve. Consumer Surplus When people buy something for less than it is worth to them, they receive a consumer surplus. Consumer surplus: Value (or marginal benefit) of a good minus the price paid for it, summed over the quantity bought. It is the triangle are under the demand curve, but above market price. E.g. Lisa buys 30 slices of pizza at $1 a slice per month because the 30th slice is worth exactly $1 to her. But Lisa is willing to pay $2 for the 10th slice, so her marginal benefit from this slice is $1 more than she pays for it—she receives a surplus of $1 on the 10th slice.
Chapter 5: Efficiency and Equity Lisa’s consumer surplus is the sum of the surpluses on all of the slices she buys. The area of this triangle is equal to its base (30 slices) multiplied by its height ($1.50) divided by 2 = $22.50
Supply and Marginal Cost Supply, Cost, and Minimum Supply Price Consumers distinguish between value and price Producers distinguish between cost and price. Cost is what a producer gives up, price is what a producer receives. Marginal cost is the minimum price that producers must receive to induce them to offer one more unit of a good/service. The minimum supplyprice determines supply. A supply curve is a marginal cost curve. Individual Supply and Market Supply Individual supply: The relationship between the price of a good and the quantity supplied by one producer. Market supply: The relationship between the price of a good and the quantity supplied by all producers. The market supply curve is the horizontal sum of the individual supply curves and is formed by adding the quantities supplied by all the producers at each price.
Chapter 5: Efficiency and Equity E.g. At a price of $15 a pizza, Max supplies 100 pizzas and Mario 50 pizzas. So the quantity supplied by the market at $15 a pizza is 150 pizzas. 100 + 50 The market supply curve is the marginal social cost (MSC) curve. Producer Surplus When price exceeds marginal cost, the firm receives a producer surplus. Producer surplus: Price received for a good minus its minimum supplyprice (or marginal cost), summed over the quantity sold. E.g. Max sells pizzas for 15$ each. At this price, he sells 100 pizzas a month bcus the 100 th pizza costs him $15 to produce. But Max is willing to produce the 50th pizza for his marginal cost, which is $10, so he receives a surplus of 5$ on this pizza. Max’s producer surplus is the sum of the surpluses on the pizza he sells. The sum is the area of the blue triangle—the area below the market price and above the supply curve. The base (100) multiplied by its height ($10) divided by 2 = $500. The producer surplus for the market is the sum of the producer surpluses of Max and Mario.
Is the Competitive Market Efficient? Efficiency of Competitive Equilibrium In competitive equilibrium: (1) Marginal social benefit (MSB) = Marginal social cost (MSC).
Chapter 5: Efficiency and Equity (2) Resource allocation is efficient. (3) Total surplus (=consumer surplus + producer surplus) is maximized. Underproduction and Overproduction Inefficiency (from underproduction or overproduction) of measured by deadweight loss— decrease in total surplus below efficient levels.
Chapter 5: Efficiency and Equity Obstacles to Efficiency (1) Price and quantity regulations: Price regulations can put a cap on the rent a landlord can charge, or laws that require employers to pay a minimum wage, sometimes block the price adjustments that balance the quantity demanded and the quantity supplied. Quantity regulations can limit the amount a farm produces. Both lead to underproduction. (2) Taxes and Subsidies: Taxes increase the prices paid by buyers and lower the prices received by sellers. Taxes decrease the quantity produced and lead to underproduction. Subsidies (payments by the gov to producers), decrease the prices paid by buyers and increase the prices received by sellers. It creates increase in the quantity produced and lead to overproduction. (3) Externalities: An externality is a cost or benefit that affects someone other than the seller of the buyer. An external cost arises when an electric utility burns coal and emits carbon dioxide which cause climate change, which results in overproduction. An external benefit arises when an apartment owner installs a smoke detector and decreases her neighbor’s fire risk. The result is underproduction. (4) Public Goods and Common Resources: A public good is a good or service that is consumed simultaneously by everyone even if they don’t pay for it. E.g. National defense. Competitive markets would underproduce national dense bcus it is in each person interest to free ride on everyone else and avoid paying for her or hi shared of such a good. A common resource is owned by no one but available to be used by everyone. E.g. Atlantic cod. It is in everyone’s selfinterest to ignore the costs hey impose on others when they deiced how much of a common resource to use. The result is that the resource is overused. (5) Monopoly: A monopoly is a firm that is the sole provider of a good or service. E.g. Water supply, cable tv. The monopoly’s selfinterest is to maximize its profit, restrict output. The monopoly produces too little and charges too high, leading to underproduction.
Chapter 5: Efficiency and Equity (6) High Transaction Costs Opportunity costs of making trades in a market. When transaction costs are high, the market might underproduce. Is the Competitive Market Fair? Ideas about fairness divide into 2 approaches: (1) Its not fair if the result isn’t fair. There should be equality of incomes. Utilitarianism: 19 th century idea that only equality brings efficiency. It is a principle that states that we should strive to achieve “the greatest happiness for the greatest number”, by transferring income from the rich to the poor. Income transfers create the big tradeoff between efficiency and fairness. Transfers use scarce resources and weaken incentives, so a more equally shared pie results in a smaller pie. Modified utilitarianism—after incorporating costs of income transfers, result should make the poorest person as well off as possible. (2) Its not fair if the rules aren’t fair. Based on the symmetry principle, which is the requirement that ppl in similar situations be treated similarly. In economic life, this principle translates into equality of opportunity. Requires property rights and voluntary exchange.
Chapter 9: Possibilities, Preferences, and Choices Consumption Possibilities Budget line: Shows the limits to household consumption, given income, and prices of goods and services. The numbers in the table and the points A through F in the graph describe Lisa’s consumption possibilities.
Divisible goods: Goods that can be bought in any quantity desired along the budget line. E.g. Gasoline, electricity. Divisible goods are the intermediate points between A through F. Invisible goods must be bought in whole units at the points marked (E.g. movies)
Chapter 9: Possibilities, Preferences, and Choices The budget line can be described by using a budget equation. Expenditure = Income. Budget Equation Formula: PpQp + PmQm = Y Pp=price of pop, Qp=Quantity of pop, Pm=Price of movie, Qm=quantity of movie, Y=income Real income: A households real income is its income expressed as a quantity of goods that the household can afford to buy. Relative Price Price of one good divided by the price of another. A change in the relative price changes the opportunity cost and changes the slope of the budget line. A Change in Prices
Chapter 9: Possibilities, Preferences, and Choices A change in prices will change the budget line. The lower the price of the good measured on the xaxis, the flatter is the budget line. The higher the price of the good measured on the xaxis, the steeper is the budget line.
A change in Income A change in money income changes real income but does not change the relative price. The budget line shifts, but its slope does not change. A increase in money income increases real income and shifts the budget line rightward. A decrease in money income increases real income and shifts the budget line leftward.
Preferences and Indifference Curves A preference map is based on the intuitively appealing idea that people can sort all the possible combinations of goods into three groups: Preferred, not preferred, and indifferent.
Chapter 9: Possibilities, Preferences, and Choices The green curve (the indifference curve), is the key element in a preference map and is called an indifference curve. It is all the combinations of movies and pop that are just as acceptable to Lisa as her current situation at point C. The yellow part, above the indifference curve, is also the preferred combinations. Indifference Curve: Line that shows combinations of goods among which a consumer is indifferent. There are many families of indifference curves. Here is another example:
All 3 curves are indifference curves. Lisa prefers any point on curve I2 to any point on curve I1, and she prefers any point on I1 to any point on I0. I2 is a higher indifference curve than I1, and I1 is a higher indifference curve than I0. A preference map is a series of indifference curves that resemble the contour lines on a map. Indifference curves generally slope downward because it shows that when a person gives up some of good “x” they must increase their consumption of good “y” to remain indifferent.
Chapter 9: Possibilities, Preferences, and Choices Indifference curves bow toward the origin (convex) because the more of good “x” that you consume the less you are willing to give up of good “y” to get more of good “x” and remain indifferent. Indifference curves farther from the origin represent higher levels of satisfaction. Indifference curves never intersect. Marginal Rate of Substitution (MRS) Marginal Rate of Substitution (MRS): The rate at which a person will give up good “y” (the good measured on the yaxis) to get an additional unit of good “x” (the good measured on the x axis) while remaining indifferent (remaining on the same indifference curve). The magnitude of the slope of an indifference curve measures the marginal rate of substitution. If the indifference curve is steep, the marginal rate of substitution is high. The person is willing to give up a large quantity of good “y” to get an additional unit of good “x” while remaining indifferent. If the indifference curve is flat, the marginal rate of substitution is low. The person is willing to give up a small amount of good “y” to get an additional unit of good “x” while remaining indifferent.
Chapter 9: Possibilities, Preferences, and Choices How to calculate the marginal rate of substitution: The red line at point C tells us that Lisa is willing to give up 10 cases of pop to see 5 movies. 10 / 5 = 2, so the marginal rate of substitution at point C is 2. The red line at point G tells us that Lisa is willing to give up 4.5 cases of pop to see 9 movies. 4.5 / 9 = 1/2, so the marginal rate of substitution at point G is ½ As Lisa sees more movies and buys less pop, her marginal rate of substitution diminishes. Diminishing marginal rate of substitution is the key assumption about preferences. A diminishing marginal rate of substitution is a general tendency for a person to be willing to give up less of a good “y” to get on more unit of good “x”, while at the same time remaining indifferent as the quantity of x increases. The general rule is, the greater the number of movies you see, the smaller is the quantity of pop you are willing to give up to see one additional movie. The shape of a person’s indifference curves incorporates the principle of the diminishing marginal rate of substitution because the curves are bowed towards the origin. More substitutability between goods yields straighter indifference curves. Less substitutability between goods yields more tightly curved indifference curves. Degree of Substitutability Most of us would not regard movies and pop as being close substitutes, but they are substitutes because for example, no matter how much you love going to the movies, some number of cans of pop will compensate you for being deprived of seeing one movie. A person’s indifference curves for movies and pop might look something like those for most ordinary goods and services as seen in the picture.
Chapter 9: Possibilities, Preferences, and Choices
Close substitutes: When 2 goods are perfect substitutes, their indifference curves are straight lines that slope downward, as seen in the picture below. The marginal rate of substitution is constant.
Chapter 9: Possibilities, Preferences, and Choices
Complements: Indifference curves of perfect complements are Lshaped.
Chapter 9: Possibilities, Preferences, and Choices Predicting Consumer Choices Best Affordable Choice Point C is the best affordable choice. The best affordable point is on the budget line. Lisa prefers all the points on the budget line between F and H to point I. Every point on the budget line lies on an indifference curve. Point C is the highest attainable indifference curve. Marginal rate of substitution equals relative price. At point C, Lisa’s marginal rate of substitution between movies and pop is equal to the relative price of movies and pop. Lisa’s willingness to pay for a movie equals her opportunity cost of a movie.
A Change in Price Price Effect: The effect of a change in the price on the quantity of a good consumed. E.g. 1. Price of a movie = $8, price of a case of pop = $4, Lisa’s income = $40. 2. Lisa buys 6 cases of pop and sees 2 movies a month at point C. 3. If the price of a movie falls to $4, with a lower price of a movie, the budget line rotates outward and becomes flatter. The new budget line is now the orange line. 4. Lisa’s best affordable point is now point J, where she sees 6 movies and drinks 4 pop.
Chapter 9: Possibilities, Preferences, and Choices 5. When the price of a movie falls and the price of pop and her income remain constant, Lisa substitutes movies for pop.
A Change in Income Income Effect: The effect of a change in income on buying plans. Lisa’s income is $40, price of a movie is $6 and pop is $4, so Lisa buys 6 movies and 4 pops, and she is at affordable point J. If her income falls to $28, her best affordable point is K. She sees 4 movies and buys 3 pops. When Lisa’s income falls, she buys less of both goods. Movies and pop are normal good.
Chapter 9: Possibilities, Preferences, and Choices
A change in income leads to a shift in the demand curve. Since Lisa’s income fell and plans to see fewer movies, her demand curve shifts leftward. A change in income shifts the budget line, changes the best affordable point, and change demand. WorkLeisure Choices Labor Supply and Labor Supply Curve The relationship between leisure and income is described by an incometime budget line. The higher wage rate has both a substitution effect and an income effect. A rising wage changes the slope of the budget line yielding: 1. Substitution effects: More time spent laboring. 2. Income effects: More income for consuming more of all normal goods, including leisure. The labor supply curve is: 1. Upwardsloping when substitution effect is higher than income effect. 2. Backwardbending when income effect is higher than substitution effect.
Chapter 10: Organizing Production The Firm and Its Economic Problem Economic goal: To predict firms’ behavior. To do so, we need to know a firm’s goal and the constraints it faces. Depreciation is the fall in the value of a firm’s capital. (E.g. Campus Sweaters’ buildings and knitting machines) Economic Profit: Equal to total revenue minus total cost, with total cost measured as the opportunity cost. The opportunity cost of production is the value of the best alternative use of the resources that a firm uses in production. A firm’s opportunity cost of production is the sum of the cost of using resources: 1. Bought in the market, 2. Owned by the firm, 3. Supplied by the firm’s owner. The firm’s opportunity cost of using the capital it owns is called the implicit rental rate of capital. The implicit rental rate of capital has two components: economic depreciation and forgone interest. Accountants measure depreciation, the fall in the value of a firms capital, using formulas that are unrelated to the change in the market value of capital. Economic depreciation: Fall in the market value of a firms capital over a given period. It equals the market price of the capital at the beginning of the period minus the market price of the capital at the end of the period. Forgone interest is an opportunity cost of production. A firm’s owner might supply both entrepreneurship and labor. The return to entrepreneurship is profit, and the profit that an entrepreneur earns on average is called normal profit. Normal profit is the cost of entrepreneurship and is a cost of production. The owner might supply labor but not take a wage. The opportunity cost of the owner’s labor is the wage income forgone by not taking the best alternative job. When an accountant does the calculations, he does not include rent forgone (on owned capital), economic depreciation (on owned capital), interest forgone (on savings account), normal profit.
Chapter 10: Organizing Production Decisions To achieve the objective of max economic profit, a firm must make five decisions: 1. What to produce and in what quantities. 2. How to produce. 3. How to organize and compensate its managers and workers. 4. How to market and price its products. 5. What to produce itself and buy from others. The Firm’s Constraints 1. Technological constraints: A technology is any method of producing a good or service. Includes the detailed designs of machines, the layout of the workplace, and the organization of the firm. The increase in profit that a firm can achieve is limited by the technology available. 2. Information constraints: A firm is constrained by limited information about the quality and efforts of its workforce, the current and future buying plans of its customers, and the plans of its competitors. 3. Market constraints The quantity each firm can sell and the price it can obtain are constrained by its customers’ willingness to pay and by the prices and marketing efforts of other firms. Technological and Economic Efficiency There are two concepts of production efficiency: technological efficiency and economy efficiency.
Chapter 10: Organizing Production Technological efficiency: Occurs when the firm produces a given output by using the least amount of inputs. Economic efficiency: Occurs when the firm produces a given output at the least cost. A technologically inefficient method is never economically efficient. Economic efficiency depends on the relative costs of resources. The economically efficient method is the one that uses a smaller amount of the more expensive resource and a large amount of the less expensive resource.
Information and Organization Firms organize production depending on which system they use, command or incentive systems. Command system: Method of organizing production that uses a managerial hierarchy. Commands pass downward through the hierarchy, and information passes upward. The military uses the purest form of command system. Managers always have incomplete information about what is happening in the division of the firm for which they are responsible. For this reason, firms use incentive systems as well as command systems to organize production . A production line is organized with a command system. Incentive Systems Method of organizing production that uses a marketlike mechanism inside the firm. Instead of using commands, senior managers create compensation schemes to induce workers to perform in ways that maximize the firms profit. Mixing the Systems
Chapter 10: Organizing Production Firms use commands when it is easy to monitor performance or when a small deviation from an ideal performance is very costly. They use incentives when monitoring performance is either not possible or too costly to be worth doing.
Principalagent problem: Problem of devising compensation rules that include an agent to act in the best interest of a principal. E.g. The stockholders of RIM are principals, and the firms managers are agents. Three ways of attempting to cope with the principleagent problem: 1. Ownership: By assigning ownership (or partownership) of a business to mangers or workers, it is sometimes possible to induce a job performance that increase a firms profits. 2. Incentive pay: Incentive based on profits, production, or sales targets. Promoting an employee. 3. Longterm contracts: A multiyear employment contract for a CEO encourages that person to take a longterm view and devise strategies that achieve maximum profit over a sustained period. Types of business Organization: 1. Sole proprietorship: Firm with a single owner, a proprietor, who has unlimited liability. Unlimited liability is the legal responsibility for all the debts of a firm up to an amount equal to the entire wealth of the owner. If a sole proprietorship cannot pay its debts, those to whom the firm owes money can claim the personal property of firm of the owner. 2. Partnership: Firm with two or more owners who have unlimited liability. Liability for the full debts of the partnership is called joint unlimited liability.
Chapter 10: Organizing Production 3. Corporation: Firm owned by one or more limited liability stockholders. Limited liability means that the owners have legal liability only for the value of their initial investment. If the corporation becomes bankrupt, its owners are not required to use their personal wealth to pay the corporations debts. Stockholders pay tax on dividends and a capital gains tax on the profit they earn when they sell a stock for a higher price than they paid for it. Corporate stocks generate capital gains when a corporation retains some of its profit and reinvests it in profitable activities. Retained earnings are taxed twice because the capital gains they generated are taxed. The different types of business organization arise from firms trying to cope with the principal agent problem.
Markets and the Competitive Environment Economists identify four market types:
Chapter 10: Organizing Production 1. Perfect competition: Arises when there are many firms, each selling an identical product, many buyers, and no restrictions on the entry of new firms into the industry. E.g. Corn, rice, and other grain crops. Most extreme form of competition. 2. Monopolistic competition: Market structure in which a large number of firms compete by making similar but slight different products. Making a product slightly different from the product of a competing firm is called product differentiation.
Chapter 10: Organizing Production E.g. In the market for pizzas, hundreds of firms make their own version of the perfect pizza. 3. Oligopoly: Market structure in which a small number of firms compete. E.g. Computer software, airplane manufacture, and internal air transportation. 4. Monopoly: Market structure in which there is only one firm and it produces a good or service that has no close substitutes and the firm is protected by a barrier preventing the entry of new firms. E.g. Telephone, gas, electricity, cable television, water suppliers, are local monopolies; monopolies restricted to a given location. Microsoft Corporation is an example of a global monopoly. Most extreme absence of competition.
Measures of Concentration Economists use two measures of concentration: 1. The fourfirm concentration ratio: Percentage of the value of sales accounted for by the four largest firms in an industry. The range of the concentration ratio is from almost zero for perfect competition to 100 percent for monopoly. This ratio is the main measure used to assess market structure. A low concentration ratio indicates a high degree of competition, and a high concentration ratio indicates an absence of competition. A monopoly has a concentration ratio of 100 percent—the largest (and only) firm has 100 percent of the sales. A fourfirm concentration ratio that exceeds 60 percent is regarded as an indication of a market that is highly concentrated and dominated by a few firms in an oligopoly. A ratio of less than 60 percent is regarded as an indication of a competitive market. 2. The HerfindahlHirschman Index:
Chapter 10: Organizing Production Also called the HHI, is the square of the percentage market share of each firm summed over the largest 50 firms (or summed over all the firms if there are fewer than 50) in a market. E.g. If there are 4 firms in a market, and the market shares of the firms are 50 percent, 25 percent, 15 percent, and 10 percent, the HerfindahlHirschman Index is: HHI = 50^2 + 25^2 + 15^2 + 10^2 = 3,450 In perfect competition, the HHI is small.
The HHI can be used to classify markets across a spectrum of types. A market in which the HHI is less than 1,000 is regarded as being competitive—the smaller the number, the greater the degree of competition. A market in which the HHI lies between 1,000 and 1,800 is regarded as being moderately competitive—a form of monopolistic completion. A market in which the HHI exceeds 1800 is regarded as being uncompetitive and a potential matter of concern for regulators. Limitations of a Concentration Measure The three main limitations of using only concentration measures as determinants of market structure are their failures to take proper account of: 1. The geographical scope of the market: Concentration measures take a national view of the market. Many goods are sold in a national market, but some are sold in a regional market and some in a global one. 2. Barriers to entry and firm turnover: Some markets are highly concentrated but entry is easy and the turnover of firms is large. E.g. small towns have few restaurants, but no restrictions hinder a new restaurants from opening and many attempt to do so. A market with only a few firms might be competitive because of potential entry. 3. The correspondence between a market and an industry : To calculate contraction ratios, Statistics Canada classifies each firm as being in a particular industry. But markets do not always correspond closely to industries for three reasons:
Chapter 10: Organizing Production First, markets are often narrower than industries. Second, most firms make several products that compete in different industries. Third, firms switch from one market to another depending on profit opportunities.
Concentration measure do provide a basis for determining the degree of completion in a market when they are combined with information about the geographical scope of the market, barriers to entry, and the extent to which large, multiproduct firms straddle a variety of markets.
Market and Firms A firm is an institution that hires factors of production and organizes them to produce and sell goods and services. Markets can coordinate production. Outsourcing is an example of market coordination. Whether a firm or markets coordinate a particular set of activities, or whether firms decide to buy from another firm or manufacture an item themselves, is a question of cost. Firms coordinate economic activity when they can perform a task more efficiently than markets can. Firms are often more efficient than markets as coordinators of economic activity because they can achieve:
Chapter 10: Organizing Production 1. Lower transactions costs: Transaction costs are the costs that arise from finding someone with whom to do business, of reaching an agreement about the price and other aspects of the exchange, and of ensuring that the terms of the agreement are fulfilled. 2. Economies of scale: When the cost of producing a unit of a good falls as its output rate increases. Arise from specialization and the division of labor that can be reaped more efficiently by a firm coordination rather than market coordination. 3. Economies of scope: Experienced by a firm when it uses specialized (and often expensive) resources to produce a range of goods and services. 4. Economies of team production: Production process in which the individuals in a group specialize in mutually supportive tasks. Because firms can economize on transactions costs, reap economies of scale and economies of scope, and organize efficient team production, it is firms rather than markets that coordinate most of our economic activity. There are however limits to the economic efficiency of firms. If a firm becomes too big or too diversified, the cost of managing its activities, per unit of output, rises. When a firm is too big, it can become more efficient by trimming down and buying more inputs in the market from other firms.
Chapter 11: Output and Costs Decision Time Frames The biggest decision that an entrepreneur makes is in what industry to establish a firm, and on the expectation that total revenue will exceed total cost. Decisions about the quantity to produce and the price to charge depend on the type of market in which the firm operates: perfect competition, monopolistic competition, oligopoly, monopoly. Decisions about how to produce a given output do not depend on the type of market. There are 2 decision time frames that study the relationship between a firm’s output decision and its costs: the short run, and the long run. The Short Run: Time frame in which the quantity of at least one factor of production is fixed. Capital, land, and entrepreneurship are fixed factors of production. Labor is the variable factor of production. Fixed factors of production are the firm’s plant: In the short run, a firm’s plant is fixed. To increase output in the short run, a firm must increase the quantity of a variable factor of production, which is usually labor. Short run decisions are easily reversed. The Long Run Time frame in which the quantities of all factors of production can be varied. The long run is a period in which the firms can change its plant. Long run decisions are not easily reversed. Sunk cost: Past expenditure on a plant that has no resale value. A sunk cost is irrelevant to the firms current decisions. The only costs that influence its current decision are the shortrun cost of changing its labor inputs and the longrun cost of changing its plant.
Chapter 11: Output and Costs ShortRun Technology Constraint The relationship between output and the quantity of labor employed is described by 2 related concepts: total product, marginal product, and average product. These product concepts can be illustrated either by product schedules or by product curves.
Product Schedules Total product: Maximum output that a given quantity of labor can produce. Marginal product: of labor is the increase in total product that results from a oneunit increase in the quantity of labor employed, other inputs remaining the same. Average product: of labor is equal to the total product divided by the quantity of labor employed. Tells how productive workers are on average. Product Curves Graphs of the relationships between employment and the three product concepts. Total Product Curve Similar to the production possibilities frontier. All the points above the curve are unattainable. Points that lie below the curve, in the orange area, are attainable, but inefficient. They use more labor than is necessary to produce a given output. Only the points on the total product curve are technologically efficient.
Chapter 11: Output and Costs Marginal Product Curve Total Product: The orange bars illustrate the marginal product of labor. The height of a bar measures marginal product. Marginal product is also measured by the slope of the total product curve.
Marginal Product: The height of this curve measures the slope of the total product curve at a point.
Chapter 11: Output and Costs
The shapes of the product curves are similar because almost every production process has 2 features: increasing marginal returns initially, and diminishing marginal returns eventually. Increasing Marginal Returns: Occurs when the marginal product of an additional worker exceeds the marginal product of the previous worker. Increasing marginal returns arise from increased specialization and division of labor in the production process. Diminishing Marginal Returns: Occurs when the marginal product of an additional worker is less than the marginal product of the previous worker. All production processes eventually reach a point of diminishing marginal return. Arises from the fact that more and more workers are using the same capital and working in the same space. The law of diminishing returns: As a firm uses more of a variable factor of production, with a given quantity of the fixed factor of production, the marginal product of the variable factor eventually diminishes. Average Product Curve Average product is largest when average product and marginal product are equal.
Chapter 11: Output and Costs For the numbers of workers at which marginal product exceeds average product, average product is increasing. For the number of workers at which marginal product is less than average product, average product is decreasing. ShortRun Cost To produce more output in the short run, a firm must employ more labor, which means that it must increase its costs. The relationship between output and costs is described by using three cost concepts: total cost, marginal cost, and average cost. Total Cost A firms total cost (TC) is the cost of all the factors of production it uses. Total cost is separated into total fixed cost and total variable cost. Total fixed cost (TFC): Cost of the firm’s fixed factors. The quantities of fixed factors don’t change as output changes, so total fixed cost is the same at all outputs. Total variable cost (TVC): Cost of the firms variable factors. Total variable cost changes as output changes. Total cost is the sum of total fixed costs and total variable cost: TC=TFC+TVC Marginal Cost A firm’s marginal cost is the increase in total cost that results from a oneunit increase in output. We calculate marginal cost as the increase in total cost divided by the increase in output. E.g. Output increases from 10 sweaters to 13 sweaters, total cost increases from $75 to $100. The change in output is 3 sweaters, and the change in total cost is $25. The marginal cost of one of those 3 sweaters ($25/3) which equals $8.33. At small outputs, marginal cost decreases as output increases because of greater specialization and the division of labor, but as output increases further, marginal cost eventually increase because of the law of diminishing returns. Marginal cost tells us how total cost changes as output increases. Average Cost Three average costs of production are: average fixed cost, average variable cost, and average total cost. Average fixed cost (AFC): Total fixed cost per unit of output.
Chapter 11: Output and Costs Average variable cost (AVC): Total variable cost per unit of output. Average total cost (ATC): Total cost per unit of output. The average cost concepts are calculated from the total cost concepts: TC= TFC+TVC. Divide each total cost term by the quantity produced Q: TC = TFC + TVC or ATC = AFC + AVC. Q Q Q Marginal Cost and Average Cost The marginal cost curve (MC) intersects the average variable cost curve and the average total cost curve at their minimum points. When marginal cost is less than average cost, average cost is decreasing, and when marginal cost exceeds average cost, average cost is increasing. Why the Average Total Cost Curve is UShaped Average total cost is the sum of average fixed cost and average variable cost, so the shape of the ATC curve combines the shapes of the AFC and AVC curves. U shape of the ATC curve arises from the influence of two opposing forces: 1. Spreading total fixed costs over a larger output. 2. Eventually diminishing returns. Diminishing returns means that as output increases, everlarger amounts of labor are needed to produce an additional unit of output. As output increases, average variable cost decreases initially but eventually increases, and the AVC curve slopes upward. The AVC curve is Ushaped. As output increase, both average fixed costs and average variable cost decrease, so average total cost decreases. The ATC curve slopes downward. Shifts in the Cost Curves The position of a firm’s shortrun cost curves depends on two factors: technology and prices of factors of production. Technology: Lowers the cost of production and shifts the cost curves downward. Prices of factors of production: An increase in the price of a factor of production increases the firms costs and shifts its cost curves. LongRun Cost
Chapter 11: Output and Costs Depends on the firms production function, which is the relationship between the maximum output attainable and the quantities of both labor and capital. The Production Function The marginal product of capital is the change in total product divided by the change in capital when the quantity of labor is constant. Each shortrun TC curve is Ushaped. For each shortrun ATC curve, the larger the plant, the greater is the output at which average total cost is at minimum. The longrun average cost curve is the relationship between the lowest attainable average total cost and output when the firm can change both plant it uses and the quantity of labor it employs. Economics of scale are features of a firm’s technology that make average total cost fall as output increases, and the LRAC curve slopes downward. Diseconomies of scale are features of a firms technology that make average total cost rise as output increases, and the LRAC curve slopes upward. Constant returns of scale are features of a firms technology that keep average total cost constant as output increases, and the LRAC curve is horizontal. A firm’s minimum efficient scale is the smallest output at which longrun average cost reaches its lowest level.
Chapter 12: Perfect Competition What is Perfect Competition? Raw competition. Extreme form of competition. Market in which: 1. Many firms sell identical products to many buyers. 2. There are no restrictions on entry into the market. 3. Established firms have no advantage over new ones. 4. Sellers and buyers are well informed about prices. E.g. of highly competitive industries: Farming, fishing, wood pulping and paper milling, the manufacture of paper cups and shopping bags, grocery retailing, photo finishing, lawn services, plumbing, painting, dry cleaning, and laundry services. Perfect competition arises if the minimum efficient scale of a single producer is small relative to the market demand for the good/service, which means that there is room for many firms. A firm’s minimum efficient scale is the smallest output at which longrun average cost reaches its lowest level. Each firm produces a good that has no unique characteristics, so consumers don’t care which firm’s good they buy. Firms in perfect competition are price takers. A price taker is a firm that cannot influence the market price because its production is an insignificant part of the total market. A firm’s goal is to maximize economic profit, which is equal total revenue minus total cost. E.g. Revenue Concepts: The market demand curve D and market supply curve S determine the market price. The market price is $25/sweater, so the most that Campus Sweaters can sell a sweater is $25.
Chapter 12: Perfect Competition
A firm’s total revenue equals the price of its output multiplied by the number of units of output sold (price x quantity). E.g. If Campus Sweater sells 9 sweaters, its total revenue is $225. (9 x $25 = $225). TR= Total revenue curve. Because each additional sweater sold brings in a constant amount $25the total revenue curve is an upward–sloping straight line .
Marginal revenue is the change in total revenue that results from a oneunit increase in the quantity sold. It is calculated by dividing the change in total revenue by the change in the quantity sold.
Chapter 12: Perfect Competition E.g. When the quantity sold increases from 8 to 9 sweaters, total revenue increases from $200 to $225, so marginal revenue is $25 a sweater. In perfect completion, the firm’s marginal revenue equals the market price. The firm’s marginal revenue curve (MR) shows as the horizontal line at the market price.
The demand curve for the firm’s product is a horizontal line at the market price, the same as the firms marginal revenue curve because the firm can sell any quantity it chooses at the market price. A horizontal demand curve illustrates a perfectly elastic demand, so the demand for the firm’s product is perfect elastic. A sweater from Campus Sweaters is a perfect substitute for a sweater from any other factory. The market demand for sweaters is not perfectly elastic: Its elasticity depends on the substitutability of sweaters for other goods/services. For a firm to achieve its goal to maximize economic profit, it must decide: 1. How to produce at minimum cost. 2. What quantity to produce. 3. Whether to enter or exit a market. A firm makes the first decision by operating with the plant that minimizes longrun average costby being on its longrun average cost curve. The Firm’s Output Decision A firm’s cost curves (total cost, average cost, and marginal cost) describe the relationship between its output and costs.
Chapter 12: Perfect Competition A firm’s revenue curves (total revenue and marginal revenue) describe the relationship between its output and revenue. From the firm’s cost curves and revenue curves, we can find the output that maximizes the firm’s economic profit. When the firm makes zero economic profit, it is called a breakeven point. Another way to find the profit maximizing output is to use marginal analysis, which compares marginal revenue, MR, with marginal cost. At low output levels, the firms incurs an economic loss, it cant cover its fixed costs. At intermediate output levels, the firm makes an economic profit. At high output levels, the firm again incurs an economic loss—now the firm faces steeply rising costs because of diminishing returns. The firm’s total cost equals total fixed cost (TFC) plus total variable cost (TVC) Total variable cost (TVC) varies with the amount of output produced. It is zero if the firm produces nothing. Total fixed cost (TFC) does not vary with the amount of output produced. Even if the firm produces nothing, it still has to pay the TFC. A firm’s shutdown point is the price and quantity at which it is indifferent between producing and shutting down. This point is where AVC is at its minimum, and where the MC curve crosses the AVC curve. At the shutdown point, the firm is indifferent between producing and shutting down temporarily. The firm incurs a loss equal to TFC from either action. A perfectly competitive firm’s supply curve shows how the firm’s profitmaximizing output varies as the market price varies, other things remaining the same. Output, Price, and Profit in the Short Run Profits and Losses in the Short Run Maximum profit is not always a positive economic profit. To determine whether a firm is making an economic profit or incurring an economic loss, we compare the firm’s average total cost at the profitmaximizing output with the market price. The shortrun market supply curve shows the quantity supplied by all firms in the market at each price when each firm’s plant and the number of firms remain the same. If price equals average total cost, the firm makes zero economic profit (breaks even).
Chapter 12: Perfect Competition If price exceeds average total cost, the firm makes a positive economic profit. If price is less than average total cost, the firm incurs an economic loss—economic profit is negative. The quantity supplied by the market at any given price is the sum of the quantities supplied by all the firms in the market at that price. At a price equal to minimum AVC, the shutdown price, some firms will produce the shutdown quantity and others will produce zero. The market supply curve is perfectly elastic. Shortrun market supply and market demand determine the market price and output. An increase in demand bring a rightward shift of the market demand curve: The price rises and the quantity increases. A decrease in demand brings a leftward shift of the demand curve: The price falls and the quantity decreases. Output, Price, and Profit in the Long Run In shortrun equilibrium, a firm may make an economic profit, break even, or incur an economic loss. Only one of them is a longrun equilibrium because firms can enter or exit the market. New firms enter an industry in which existing firms make an economic profit. Firms exit an industry in which they incur an economic loss. New firms have an incentive to enter the market. When they do, the market supply increases and the market price falls. Firms enter as long as firms are making economic profits. In the long run, the market supply increase, the market price falls and the firms make zero economic profit. Firms exist as long as firms are incurring economic losses. In the long run, the market supply decrease, the market price rises until firms make zero economic profit. Changing Tastes and Advancing Technology A decrease in demand shifts the market demand curve leftward. The price falls and the quantity decreases. The market price falls, and each firm decrease the quantity it produces. The market price is now below each firms minimum average total cost, so firms incur economic losses. Economic losses induce some firms to exit in the long run, which decreases the market supply and the price starts to rise. As the price rises, the quantity produced by all firms continues to decrease as more firms exit, but each firm remaining in the market starts to increase its quantity.
Chapter 12: Perfect Competition A new longrun equilibrium occurs when the price has risen to equal minimum average total cost. Firms make zero economic profits, and firms no longer exit the market. The main diff between the initial and new longrun equilibrium is the number of firms in the market. Fewer firms produce the equilibrium quantity. A permanent increase in demand shifts the demand curve rightward. The price rises and the quantity increases. Economic profit induces entry, which increase shortrun supply and shifts the shortrun market supply curve rightward. As the market supply increase, the price falls and the market quantity continues to increase. With a falling price, each firm decreases its output as it moves along its marginal cost curve (supply curve). A new longrun equilibrium occurs when the price has fallen to equal minimum average total cost. Firms make zero economic profit, and firms have no incentive to enter the market. The main difference between the initial and new longrun equilibrium is the number of firms. In the new equilibrium, a larger number of firms produce the equilibrium quantity. The change in the longrun equilibrium price following a permanent change in demand depends on external economies and external diseconomies. External economies are factors beyond the control of an individual firm that lower the firm’s costs as the industry output increases. External diseconomies are factors beyond the control of a firm that raise the firm’s costs as industry output increases. In the absence of external economies or external diseconomies, a firm’s costs remain constant as the market output changes. The longrun market supply curve shows how the quantity supplied in a market varies as the market price varies after all the possible adjustments have been made, including changes in each firm’s plant and the number of firms in the market. In the absence of external economies or external diseconomies, an increase in demand does not change the price in the long run. The longrun market supply curve is horizontal. When external diseconomies are present, an increase in demand brings a higher price in the long run. The longrun market supply curve is upward sloping. when external economies are present, an increase in demand brings a lower price in the long run. The longrun market supply curve is downward sloping.
Chapter 12: Perfect Competition A new technology enables firms to produce at a lower average cost and a lower marginal cost— firms’ cost curves shift downward. Firms that adopt the new technology make an economic profit. Newtechnology firms enter and oldtechnology firms either exit or adopt the new technology. Industry supply increases and the industry supply curve shifts rightward. The price falls and the quantity increases. Eventually, a new longrun equilibrium emerges in which all firms use the new technology, the price equals minimum average total cost, and each firm makes zero economic profit.