Final

Chapter 1: Ten Principles of Economics

Core Skills

• Identify trade-offs in everyday decisions: Recognize that choosing one course of action involves sacrificing alternatives.

• Compute and interpret opportunity cost: Determine what must be given up to obtain a specific item or engage in a specific activity.

• Apply marginal analysis: Compare marginal benefit ($MB$) versus marginal cost ($MC$) to make optimal decisions. Rational decision-makers take an action if and only if MB > MC.

• Recognize incentives and predict behavioral responses: Understand that people respond to changes in costs and benefits, and predict how behavior shifts when incentives change.

• Distinguish between efficiency and equality:   - Efficiency: The property of society getting the maximum benefits from its scarce resources (the size of the economic pie).   - Equality: The property of distributing economic prosperity uniformly among the members of society (how the pie is sliced).

• Identify examples of market failure: Recognize situations in which a market left on its own fails to allocate resources efficiently.

Core Concepts

• Scarcity and choice: Since resources are limited, society cannot produce all the goods and services people wish to have.

• Opportunity cost: The best alternative sacrificed for a chosen option.

• Marginal thinking: Small incremental adjustments to a plan of action.

• Incentives: Something (such as the prospect of a punishment or a reward) that induces a person to act.

• Gains from trade: Trade allows people and nations to specialize in what they do best and enjoy a greater variety of goods and services.

• Markets and the “invisible hand”: The phenomenon where households and firms interacting in markets act as if guided by an "invisible hand" that leads them to desirable market outcomes.

• Government roles:   - Property rights: The ability of an individual to own and exercise control over scarce resources.   - Correcting externalities: Intervening when one person’s actions impact the well-being of a bystander (e.g., pollution).

• Productivity and living standards: A country's standard of living depends on its ability to produce goods and services. High productivity leads to high living standards.

• Money growth and inflation: Inflation is an increase in the overall level of prices in the economy. It is primarily caused by large growths in the quantity of money, which decreases the value of money.

• Short-run tradeoff between inflation and unemployment: In the short run, many economic policies push inflation and unemployment in opposite directions, often illustrated by the Phillips Curve.

Chapter 2: Thinking Like an Economist

Core Skills

• Distinguish positive vs. normative statements:   - Positive statements: Claims that attempt to describe the world as it is (descriptive; can be tested/verified).   - Normative statements: Claims that attempt to prescribe how the world should be (prescriptive; involve value judgments).

• Interpret and draw Production Possibilities Frontiers (PPFs): Understand the graph that shows the combinations of output that the economy can possibly produce given the available factors of production and technology.

• Identify efficient, inefficient, and unattainable points:   - Efficient: Points on the PPF curve.   - Inefficient: Points inside the PPF curve (resources underutilized).   - Unattainable: Points outside the PPF curve (given current resources/technology).

• Explain increasing opportunity cost: The concept that as you produce more of one good, the opportunity cost of producing an additional unit rises, resulting in a bowed-out (concave) PPF.

• Understand and apply the circular-flow diagram: A visual model of the economy that shows how dollars flow through markets among households and firms.

Core Concepts

• Scientific method in economics: The dispassionate development and testing of theories about how the world works based on observation.

• Role of assumptions: Economists use assumptions to simplify the complex world and make it easier to understand.

• Economic models: Simplified representations of reality, often composed of diagrams and equations.

• Microeconomics vs. macroeconomics:   - Microeconomics: The study of how households and firms make decisions and how they interact in markets.   - Macroeconomics: The study of economy-wide phenomena, including inflation, unemployment, and economic growth.

• Positive vs. normative analysis: The distinction between evaluating objective facts and subjective values.

Chapter 3: Interdependence & the Gains from Trade

Absolute vs. Comparative Advantage

• Absolute Advantage: The ability to produce a good using fewer inputs than another producer (i.e., producing more with the same inputs).

• Comparative Advantage: The ability to produce a good at a lower opportunity cost than another producer. It is impossible for one person to have a comparative advantage in both goods if the opportunity costs are different.

Specialization & Terms of Trade

• Specialization: Each party specializes in the production of the good for which it has a comparative advantage.

• Terms of Trade: For both parties to gain from trade, the price at which they trade must lie between the two parties' opportunity costs.

Expanding Consumption Possibilities

• Trade allows consumption beyond each party’s PPF: While a party cannot produce outside its PPF, through trade, it can reach a consumption point that was previously unattainable.

• Gains from trade: Arise from comparative advantage rather than absolute advantage.

• Example: If two producers divide labor and exchange outputs, provided mutually beneficial trade occurs, parties will produce and trade their surplus.

Applications of Comparative Advantage

• Imports: Goods produced abroad and sold domestically.

• Exports: Goods produced domestically and sold abroad.

Policy Implications

• National Gains: Countries as a whole gain from free trade because it allows for greater total production and consumption.

• Distributional Impacts: While there is an aggregate welfare gain, some domestic groups (such as workers in industries competing with imports) may lose. The political debate often centers on these distributional impacts versus aggregate welfare.

Chapter 4: Supply and Demand

Core Skills

• Draw and interpret supply and demand curves: Demand is downward-sloping; Supply is upward-sloping.

• Identify shifts vs. movements along curves:   - Movement along curve: Caused by a change in the price of the good itself (Change in Quantity Demanded/Supplied).   - Shift of curve: Caused by a change in a non-price determinant (Change in Demand/Supply).

• Predict equilibrium changes using the three-step method:   1. Decide whether the event shifts the supply or demand curve.   2. Decide in which direction the curve shifts.   3. Use the supply-and-demand diagram to see how the shift changes the equilibrium price and quantity.

• Identify substitutes and complements:   - Substitutes: Two goods for which an increase in the price of one leads to an increase in the demand for the other.   - Complements: Two goods for which an increase in the price of one leads to a decrease in the demand for the other.

• Classify goods as normal or inferior:   - Normal good: A good for which an increase in income leads to an increase in demand.   - Inferior good: A good for which an increase in income leads to a decrease in demand.

Core Concepts

• Law of demand: The claim that, other things being equal, the quantity demanded of a good falls when the price of the good rises.

• Law of supply: The claim that, other things being equal, the quantity supplied of a good rises when the price of the good rises.

• Determinants of demand: Income, prices of related goods, tastes, expectations, and the number of buyers.

• Determinants of supply: Input prices, technology, expectations, and the number of sellers.

• Market equilibrium: A situation in which the market price has reached the level where quantity supplied equals quantity demanded.

• Surpluses and shortages:   - Surplus: Quantity supplied > Quantity demanded (excess supply).   - Shortage: Quantity demanded > Quantity supplied (excess demand).

• Effects of expectations: Future expectations of price or income can shift current demand or supply curves.

Chapter 5: Elasticity

Core Skills

• Compute price elasticity using the midpoint formula:   $\text{Price Elasticity of Demand} = \frac{(Q_2 - Q_1) / [(Q_2 + Q_1) / 2]}{(P_2 - P_1) / [(P_2 + P_1) / 2]}$

• Interpret elasticity values:   - Elastic: Value > 1 (Quantity responds substantially to price changes).   - Inelastic: Value < 1 (Quantity responds only slightly to price changes).   - Unit Elastic: Value $= 1$.

• Predict revenue changes from price changes:   - If demand is inelastic, price and total revenue move in the same direction.   - If demand is 转化, price and total revenue move in opposite directions.   - If demand is unit elastic, total revenue remains constant as price changes.

• Identify determinants of elasticity: Availability of close substitutes, necessities vs. luxuries, definition of the market (narrow vs. broad), and time horizon.

• Compute income and cross-price elasticities:   - Income Elasticity: $\frac{\%\Delta Q_d}{\%\Delta \text{Income}}$. Positive for normal goods, negative for inferior goods.   - Cross-Price Elasticity: $\frac{\%\Delta Q_{d1}}{\%\Delta P_2}$. Positive for substitutes, negative for complements.

• Distinguish elastic vs. inelastic supply: Reflects the flexibility of sellers to change the amount of the good they produce.

Core Concepts

• Total revenue and elasticity: $\text{Total Revenue} = P \times Q$.

• Time horizon and elasticity: Goods tend to have more elastic demand and supply over longer time horizons.

Chapter 6: Government Policies (Price Controls and Taxes)

Core Skills

• Identify binding vs. non-binding price ceilings and floors:   - Binding Ceiling: Set below equilibrium price, causes a shortage.   - Binding Floor: Set above equilibrium price, causes a surplus.

• Analyze tax incidence: The study of who bears the burden of taxation. It is rarely shared equally between buyers and sellers.

• Draw tax wedges and compute tax revenue: A tax creates a "wedge" between the price buyers pay and the price sellers receive.   $\text{Tax Revenue} = \text{Tax Per Unit} \times \text{Quantity Sold with Tax} ($Q_{tax}$)$.

• Determine which side bears more burden using elasticity: The tax burden falls more heavily on the side of the market that is less elastic (more inelastic).

Core Concepts

• Price ceilings (rent control): A legal maximum on the price at which a good can be sold.

• Price floors (minimum wage): A legal minimum on the price at which a good can be sold.

• Per-unit taxes: A tax levied as a fixed amount for every unit of a good sold.

• Deadweight loss (DWL): The fall in total surplus that results from a market distortion, such as a tax.

• Elasticity and DWL size: The greater the elasticities of supply and demand, the greater the deadweight loss of a tax.

Chapter 7: Consumers, Producers, and Market Efficiency

Core Skills

• Compute consumer surplus (CS), producer surplus (PS), and total surplus (TS):   - CS: $\text{Willingness to Pay} - \text{Price Paid}$.   - PS: $\text{Price Received} - \text{Cost to Seller}$.   - TS: $CS + PS$ or $\text{Valuation by Buyers} - \text{Cost to Sellers}$.

• Identify CS and PS graphically: CS is the area below the demand curve and above the price. PS is the area above the supply curve and below the price.

• Evaluate efficiency of market outcomes: An allocation of resources is efficient if it maximizes total surplus.

• Predict how price controls affect surplus: Price controls usually lead to a reduction in total surplus (Deadweight Loss).

Core Concepts

• Willingness to pay: The maximum amount that a buyer will pay for a good.

• Willingness to sell / cost: The value of everything a seller must give up to produce a good.

• Efficiency of competitive markets: In the absence of market failures, the equilibrium of supply and demand maximizes total surplus.

• Equity vs. efficiency: The trade-off between maximizing the total size of the economic pie and distributing it fairly.

Chapter 8: The Cost of Taxation

Core Skills

• Compute deadweight loss using triangle formulas:   $\text{DWL} = \frac{1}{2} \times \text{Tax Amount} \times (Q_{equilibrium} - Q_{tax})$

• Identify how taxes distort markets: Taxes discourage market activity; when a good is taxed, the quantity sold is smaller in the new equilibrium.

• Compare DWL under different elasticities: A more elastic curve results in a larger response in quantity, creating a larger DWL.

Core Concepts

• Tax wedge: The difference between what the buyer pays and what the seller receives.

• Laffer curve shape and intuition: A graph showing the relationship between tax rates and tax revenue. It suggests that as tax rates rise, tax revenue first increases but then eventually decreases as the high rates drastically reduce the size of the market.

• Efficiency losses from taxation: The reduction in well-being for buyers and sellers typically exceeds the revenue raised by the government.

Chapter 9: Externalities

Core Skills

• Identify positive vs. negative externalities:   - Negative: The impact on the bystander is adverse (e.g., pollution).   - Positive: The impact on the bystander is beneficial (e.g., technology spillovers).

• Draw social cost and social value curves:   - Social Cost = Private Cost + External Cost.   - Social Value = Private Value + External Benefit.

• Determine socially optimal quantity: Found where the social cost curve intersects the demand curve (for negative externalities) or where the social value curve intersects the supply curve (for positive externalities).

• Explain corrective taxes and subsidies:   - Corrective (Pigouvian) taxes: Taxes enacted to deal with the effects of negative externalities.   - Corrective subsidies: Used to encourage activities with positive externalities.

• Apply Coase theorem logic: The proposition that if private parties can bargain without cost over the allocation of resources, they can solve the problem of externalities on their own.

Core Concepts

• Tradable pollution permits: A market-based solution where the government sets a limit on pollution and labels it into permits that firms can trade.

• Transaction costs: The costs that parties incur in the process of agreeing to and following through on a bargain.

Chapter 15: Measuring a Nation’s Income (GDP)

Core Skills

• Compute nominal and real GDP:   - Nominal GDP: Production of goods and services valued at current prices.   - Real GDP: Production of goods and services valued at constant base-year prices.

• Compute GDP deflator:   $\text{GDP Deflator} = \frac{\text{Nominal GDP}}{\text{Real GDP}} \times 100$

• Compute inflation using the deflator:   $\text{Inflation Rate in Year 2} = \frac{\text{GDP Deflator in Year 2} - \text{GDP Deflator in Year 1}}{\text{GDP Deflator in Year 1}} \times 100$

• Classify items as included or excluded from GDP: Included: final goods, currently produced, within a country. Excluded: intermediate goods, used goods, illegal goods, items produced and consumed at home.

• Distinguish GDP vs. GNP:   - GDP (Gross Domestic Product): Market value of all final goods and services produced within a country.   - GNP (Gross National Product): Market value of all final goods and services produced by permanent residents of a nation, regardless of where they are located.

Core Concepts

• Expenditure approach: Summing up total spending. Formula: $Y = C + I + G + NX$   - $C$: Consumption   - $I$: Investment   - $G$: Government Purchases   - $NX$: Net Exports (Exports - Imports)

• Income approach: Summing up total income earned by factors of production.

• Production/value-added approach: Summing the value added at each stage of production.

• Limitations of GDP: Does not account for leisure, quality of environment, non-market activities, or income distribution.

Chapter 16: Measuring the Cost of Living (CPI)

Core Skills

• Compute CPI:   $\text{CPI} = \frac{\text{Price of Basket in Current Year}}{\text{Price of Basket in Base Year}} \times 100$

• Compute inflation using CPI: Percentage change in the price index from the preceding period.

• Convert dollar values across years:   $\text{Amount in Year T dollars} = \text{Amount in Year S dollars} \times \left( \frac{\text{Price Level in Year T}}{\text{Price Level in Year S}} \right)$

• Distinguish CPI vs. GDP deflator:   - CPI: Reflects prices of goods bought by consumers; includes imported goods; uses a fixed basket.   - GDP Deflator: Reflects prices of all goods produced domestically; excludes imports; uses a currently produced basket.

Core Concepts

• CPI Biases:   - Substitution bias: Consumers substitute toward goods that become relatively less expensive.   - New goods bias: The introduction of new goods increases the variety and value of the dollar.   - Quality adjustment bias: Improvements in quality increase the value of the dollar.

• Indexation: The automatic correction by law or contract of a dollar amount for the effects of inflation.

• Real vs. nominal interest rates:   - Nominal: The interest rate as usually reported without adjustment for inflation.   - Real: The interest rate corrected for inflation ($\text{Real Rate} = \text{Nominal Rate} - \text{Inflation Rate}$).

Chapter 20: Unemployment

Core Skills

• Compute unemployment rate:   $\text{Unemployment Rate} = \frac{\text{Number of Unemployed}}{\text{Labor Force}} \times 100$

• Compute labor force participation rate:   $\text{Labor Force Participation Rate} = \frac{\text{Labor Force}}{\text{Adult Population}} \times 100$

• Classify individuals:   - Employed: Those who worked as paid employees, worked in their own business, or worked as unpaid workers in a family member's business.   - Unemployed: Those who were not employed, were available for work, and had tried to find employment during the previous four weeks.   - Not in labor force: Everyone else (e.g., full-time students, retirees).

• Distinguish types of unemployment:   - Frictional: Results because it takes time for workers to search for the jobs that best suit their tastes and skills.   - Structural: Results because the number of jobs available in some labor markets is insufficient to provide a job for everyone who wants one.   - Cyclical: The deviation of unemployment from its natural rate, associated with business cycle fluctuations.

Core Concepts

• Labor force: The total number of workers, including both the employed and the unemployed.

• Discouraged workers: Individuals who would like to work but have given up looking for a job; they are not counted in the labor force.

• Natural rate of unemployment: The normal rate of unemployment around which the unemployment rate fluctuates.

• Structural causes: Minimum-wage laws, unions (collective bargaining), and efficiency wages (high wages paid by firms to increase worker productivity).

• Unemployment insurance: A government program that partially protects workers' incomes when they become unemployed.