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Principles of Economics

Key Concepts and Summary

Principles of EconomicsKey Concepts and Summary
  1. Preface
  2. 1 Welcome to Economics!
    1. Introduction
    2. 1.1 What Is Economics, and Why Is It Important?
    3. 1.2 Microeconomics and Macroeconomics
    4. 1.3 How Economists Use Theories and Models to Understand Economic Issues
    5. 1.4 How Economies Can Be Organized: An Overview of Economic Systems
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
  3. 2 Choice in a World of Scarcity
    1. Introduction to Choice in a World of Scarcity
    2. 2.1 How Individuals Make Choices Based on Their Budget Constraint
    3. 2.2 The Production Possibilities Frontier and Social Choices
    4. 2.3 Confronting Objections to the Economic Approach
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  4. 3 Demand and Supply
    1. Introduction to Demand and Supply
    2. 3.1 Demand, Supply, and Equilibrium in Markets for Goods and Services
    3. 3.2 Shifts in Demand and Supply for Goods and Services
    4. 3.3 Changes in Equilibrium Price and Quantity: The Four-Step Process
    5. 3.4 Price Ceilings and Price Floors
    6. 3.5 Demand, Supply, and Efficiency
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  5. 4 Labor and Financial Markets
    1. Introduction to Labor and Financial Markets
    2. 4.1 Demand and Supply at Work in Labor Markets
    3. 4.2 Demand and Supply in Financial Markets
    4. 4.3 The Market System as an Efficient Mechanism for Information
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  6. 5 Elasticity
    1. Introduction to Elasticity
    2. 5.1 Price Elasticity of Demand and Price Elasticity of Supply
    3. 5.2 Polar Cases of Elasticity and Constant Elasticity
    4. 5.3 Elasticity and Pricing
    5. 5.4 Elasticity in Areas Other Than Price
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  7. 6 Consumer Choices
    1. Introduction to Consumer Choices
    2. 6.1 Consumption Choices
    3. 6.2 How Changes in Income and Prices Affect Consumption Choices
    4. 6.3 Labor-Leisure Choices
    5. 6.4 Intertemporal Choices in Financial Capital Markets
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  8. 7 Cost and Industry Structure
    1. Introduction to Cost and Industry Structure
    2. 7.1 Explicit and Implicit Costs, and Accounting and Economic Profit
    3. 7.2 The Structure of Costs in the Short Run
    4. 7.3 The Structure of Costs in the Long Run
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  9. 8 Perfect Competition
    1. Introduction to Perfect Competition
    2. 8.1 Perfect Competition and Why It Matters
    3. 8.2 How Perfectly Competitive Firms Make Output Decisions
    4. 8.3 Entry and Exit Decisions in the Long Run
    5. 8.4 Efficiency in Perfectly Competitive Markets
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  10. 9 Monopoly
    1. Introduction to a Monopoly
    2. 9.1 How Monopolies Form: Barriers to Entry
    3. 9.2 How a Profit-Maximizing Monopoly Chooses Output and Price
    4. Key Terms
    5. Key Concepts and Summary
    6. Self-Check Questions
    7. Review Questions
    8. Critical Thinking Questions
    9. Problems
  11. 10 Monopolistic Competition and Oligopoly
    1. Introduction to Monopolistic Competition and Oligopoly
    2. 10.1 Monopolistic Competition
    3. 10.2 Oligopoly
    4. Key Terms
    5. Key Concepts and Summary
    6. Self-Check Questions
    7. Review Questions
    8. Critical Thinking Questions
    9. Problems
  12. 11 Monopoly and Antitrust Policy
    1. Introduction to Monopoly and Antitrust Policy
    2. 11.1 Corporate Mergers
    3. 11.2 Regulating Anticompetitive Behavior
    4. 11.3 Regulating Natural Monopolies
    5. 11.4 The Great Deregulation Experiment
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  13. 12 Environmental Protection and Negative Externalities
    1. Introduction to Environmental Protection and Negative Externalities
    2. 12.1 The Economics of Pollution
    3. 12.2 Command-and-Control Regulation
    4. 12.3 Market-Oriented Environmental Tools
    5. 12.4 The Benefits and Costs of U.S. Environmental Laws
    6. 12.5 International Environmental Issues
    7. 12.6 The Tradeoff between Economic Output and Environmental Protection
    8. Key Terms
    9. Key Concepts and Summary
    10. Self-Check Questions
    11. Review Questions
    12. Critical Thinking Questions
    13. Problems
  14. 13 Positive Externalities and Public Goods
    1. Introduction to Positive Externalities and Public Goods
    2. 13.1 Why the Private Sector Under Invests in Innovation
    3. 13.2 How Governments Can Encourage Innovation
    4. 13.3 Public Goods
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  15. 14 Poverty and Economic Inequality
    1. Introduction to Poverty and Economic Inequality
    2. 14.1 Drawing the Poverty Line
    3. 14.2 The Poverty Trap
    4. 14.3 The Safety Net
    5. 14.4 Income Inequality: Measurement and Causes
    6. 14.5 Government Policies to Reduce Income Inequality
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  16. 15 Issues in Labor Markets: Unions, Discrimination, Immigration
    1. Introduction to Issues in Labor Markets: Unions, Discrimination, Immigration
    2. 15.1 Unions
    3. 15.2 Employment Discrimination
    4. 15.3 Immigration
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
  17. 16 Information, Risk, and Insurance
    1. Introduction to Information, Risk, and Insurance
    2. 16.1 The Problem of Imperfect Information and Asymmetric Information
    3. 16.2 Insurance and Imperfect Information
    4. Key Terms
    5. Key Concepts and Summary
    6. Self-Check Questions
    7. Review Questions
    8. Critical Thinking Questions
    9. Problems
  18. 17 Financial Markets
    1. Introduction to Financial Markets
    2. 17.1 How Businesses Raise Financial Capital
    3. 17.2 How Households Supply Financial Capital
    4. 17.3 How to Accumulate Personal Wealth
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  19. 18 Public Economy
    1. Introduction to Public Economy
    2. 18.1 Voter Participation and Costs of Elections
    3. 18.2 Special Interest Politics
    4. 18.3 Flaws in the Democratic System of Government
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  20. 19 The Macroeconomic Perspective
    1. Introduction to the Macroeconomic Perspective
    2. 19.1 Measuring the Size of the Economy: Gross Domestic Product
    3. 19.2 Adjusting Nominal Values to Real Values
    4. 19.3 Tracking Real GDP over Time
    5. 19.4 Comparing GDP among Countries
    6. 19.5 How Well GDP Measures the Well-Being of Society
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  21. 20 Economic Growth
    1. Introduction to Economic Growth
    2. 20.1 The Relatively Recent Arrival of Economic Growth
    3. 20.2 Labor Productivity and Economic Growth
    4. 20.3 Components of Economic Growth
    5. 20.4 Economic Convergence
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  22. 21 Unemployment
    1. Introduction to Unemployment
    2. 21.1 How the Unemployment Rate is Defined and Computed
    3. 21.2 Patterns of Unemployment
    4. 21.3 What Causes Changes in Unemployment over the Short Run
    5. 21.4 What Causes Changes in Unemployment over the Long Run
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  23. 22 Inflation
    1. Introduction to Inflation
    2. 22.1 Tracking Inflation
    3. 22.2 How Changes in the Cost of Living are Measured
    4. 22.3 How the U.S. and Other Countries Experience Inflation
    5. 22.4 The Confusion Over Inflation
    6. 22.5 Indexing and Its Limitations
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  24. 23 The International Trade and Capital Flows
    1. Introduction to the International Trade and Capital Flows
    2. 23.1 Measuring Trade Balances
    3. 23.2 Trade Balances in Historical and International Context
    4. 23.3 Trade Balances and Flows of Financial Capital
    5. 23.4 The National Saving and Investment Identity
    6. 23.5 The Pros and Cons of Trade Deficits and Surpluses
    7. 23.6 The Difference between Level of Trade and the Trade Balance
    8. Key Terms
    9. Key Concepts and Summary
    10. Self-Check Questions
    11. Review Questions
    12. Critical Thinking Questions
    13. Problems
  25. 24 The Aggregate Demand/Aggregate Supply Model
    1. Introduction to the Aggregate Demand/Aggregate Supply Model
    2. 24.1 Macroeconomic Perspectives on Demand and Supply
    3. 24.2 Building a Model of Aggregate Demand and Aggregate Supply
    4. 24.3 Shifts in Aggregate Supply
    5. 24.4 Shifts in Aggregate Demand
    6. 24.5 How the AD/AS Model Incorporates Growth, Unemployment, and Inflation
    7. 24.6 Keynes’ Law and Say’s Law in the AD/AS Model
    8. Key Terms
    9. Key Concepts and Summary
    10. Self-Check Questions
    11. Review Questions
    12. Critical Thinking Questions
    13. Problems
  26. 25 The Keynesian Perspective
    1. Introduction to the Keynesian Perspective
    2. 25.1 Aggregate Demand in Keynesian Analysis
    3. 25.2 The Building Blocks of Keynesian Analysis
    4. 25.3 The Phillips Curve
    5. 25.4 The Keynesian Perspective on Market Forces
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
  27. 26 The Neoclassical Perspective
    1. Introduction to the Neoclassical Perspective
    2. 26.1 The Building Blocks of Neoclassical Analysis
    3. 26.2 The Policy Implications of the Neoclassical Perspective
    4. 26.3 Balancing Keynesian and Neoclassical Models
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  28. 27 Money and Banking
    1. Introduction to Money and Banking
    2. 27.1 Defining Money by Its Functions
    3. 27.2 Measuring Money: Currency, M1, and M2
    4. 27.3 The Role of Banks
    5. 27.4 How Banks Create Money
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  29. 28 Monetary Policy and Bank Regulation
    1. Introduction to Monetary Policy and Bank Regulation
    2. 28.1 The Federal Reserve Banking System and Central Banks
    3. 28.2 Bank Regulation
    4. 28.3 How a Central Bank Executes Monetary Policy
    5. 28.4 Monetary Policy and Economic Outcomes
    6. 28.5 Pitfalls for Monetary Policy
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  30. 29 Exchange Rates and International Capital Flows
    1. Introduction to Exchange Rates and International Capital Flows
    2. 29.1 How the Foreign Exchange Market Works
    3. 29.2 Demand and Supply Shifts in Foreign Exchange Markets
    4. 29.3 Macroeconomic Effects of Exchange Rates
    5. 29.4 Exchange Rate Policies
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  31. 30 Government Budgets and Fiscal Policy
    1. Introduction to Government Budgets and Fiscal Policy
    2. 30.1 Government Spending
    3. 30.2 Taxation
    4. 30.3 Federal Deficits and the National Debt
    5. 30.4 Using Fiscal Policy to Fight Recession, Unemployment, and Inflation
    6. 30.5 Automatic Stabilizers
    7. 30.6 Practical Problems with Discretionary Fiscal Policy
    8. 30.7 The Question of a Balanced Budget
    9. Key Terms
    10. Key Concepts and Summary
    11. Self-Check Questions
    12. Review Questions
    13. Critical Thinking Questions
    14. Problems
  32. 31 The Impacts of Government Borrowing
    1. Introduction to the Impacts of Government Borrowing
    2. 31.1 How Government Borrowing Affects Investment and the Trade Balance
    3. 31.2 Fiscal Policy, Investment, and Economic Growth
    4. 31.3 How Government Borrowing Affects Private Saving
    5. 31.4 Fiscal Policy and the Trade Balance
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  33. 32 Macroeconomic Policy Around the World
    1. Introduction to Macroeconomic Policy around the World
    2. 32.1 The Diversity of Countries and Economies across the World
    3. 32.2 Improving Countries’ Standards of Living
    4. 32.3 Causes of Unemployment around the World
    5. 32.4 Causes of Inflation in Various Countries and Regions
    6. 32.5 Balance of Trade Concerns
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  34. 33 International Trade
    1. Introduction to International Trade
    2. 33.1 Absolute and Comparative Advantage
    3. 33.2 What Happens When a Country Has an Absolute Advantage in All Goods
    4. 33.3 Intra-industry Trade between Similar Economies
    5. 33.4 The Benefits of Reducing Barriers to International Trade
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  35. 34 Globalization and Protectionism
    1. Introduction to Globalization and Protectionism
    2. 34.1 Protectionism: An Indirect Subsidy from Consumers to Producers
    3. 34.2 International Trade and Its Effects on Jobs, Wages, and Working Conditions
    4. 34.3 Arguments in Support of Restricting Imports
    5. 34.4 How Trade Policy Is Enacted: Globally, Regionally, and Nationally
    6. 34.5 The Tradeoffs of Trade Policy
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  36. A | The Use of Mathematics in Principles of Economics
  37. B | Indifference Curves
  38. C | Present Discounted Value
  39. The Expenditure-Output Model
  40. Answer Key
    1. Chapter 1
    2. Chapter 2
    3. Chapter 3
    4. Chapter 4
    5. Chapter 5
    6. Chapter 6
    7. Chapter 7
    8. Chapter 8
    9. Chapter 9
    10. Chapter 10
    11. Chapter 11
    12. Chapter 12
    13. Chapter 13
    14. Chapter 14
    15. Chapter 15
    16. Chapter 16
    17. Chapter 17
    18. Chapter 18
    19. Chapter 19
    20. Chapter 20
    21. Chapter 21
    22. Chapter 22
    23. Chapter 23
    24. Chapter 24
    25. Chapter 25
    26. Chapter 26
    27. Chapter 27
    28. Chapter 28
    29. Chapter 29
    30. Chapter 30
    31. Chapter 31
    32. Chapter 32
    33. Chapter 33
    34. Chapter 34
  41. References
  42. Index

24.1 Macroeconomic Perspectives on Demand and Supply

Neoclassical economists emphasize Say’s law, which holds that supply creates its own demand. Keynesian economists emphasize Keynes’ law, which holds that demand creates its own supply. Many mainstream economists take a Keynesian perspective, emphasizing the importance of aggregate demand, for the short run, and a neoclassical perspective, emphasizing the importance of aggregate supply, for the long run.

24.2 Building a Model of Aggregate Demand and Aggregate Supply

The upward-sloping short run aggregate supply (SRAS) curve shows the positive relationship between the price level and the level of real GDP in the short run. Aggregate supply slopes up because when the price level for outputs increases, while the price level of inputs remains fixed, the opportunity for additional profits encourages more production. The aggregate supply curve is near-horizontal on the left and near-vertical on the right. In the long run, aggregate supply is shown by a vertical line at the level of potential output, which is the maximum level of output the economy can produce with its existing levels of workers, physical capital, technology, and economic institutions.

The downward-sloping aggregate demand (AD) curve shows the relationship between the price level for outputs and the quantity of total spending in the economy. It slopes down because of: (a) the wealth effect, which means that a higher price level leads to lower real wealth, which reduces the level of consumption; (b) the interest rate effect, which holds that a higher price level will mean a greater demand for money, which will tend to drive up interest rates and reduce investment spending; and (c) the foreign price effect, which holds that a rise in the price level will make domestic goods relatively more expensive, discouraging exports and encouraging imports.

24.3 Shifts in Aggregate Supply

The aggregate demand/aggregate supply (AD/AS) diagram shows how AD and AS interact. The intersection of the AD and AS curves shows the equilibrium output and price level in the economy. Movements of either AS or AD will result in a different equilibrium output and price level. The aggregate supply curve will shift out to the right as productivity increases. It will shift back to the left as the price of key inputs rises, and will shift out to the right if the price of key inputs falls. If the AS curve shifts back to the left, the combination of lower output, higher unemployment, and higher inflation, called stagflation, occurs. If AS shifts out to the right, a combination of lower inflation, higher output, and lower unemployment is possible.

24.4 Shifts in Aggregate Demand

The AD curve will shift out as the components of aggregate demand—C, I, G, and X–M—rise. It will shift back to the left as these components fall. These factors can change because of different personal choices, like those resulting from consumer or business confidence, or from policy choices like changes in government spending and taxes. If the AD curve shifts to the right, then the equilibrium quantity of output and the price level will rise. If the AD curve shifts to the left, then the equilibrium quantity of output and the price level will fall. Whether equilibrium output changes relatively more than the price level or whether the price level changes relatively more than output is determined by where the AD curve intersects with the AS curve.

The AD/AS diagram superficially resembles the microeconomic supply and demand diagram on the surface, but in reality, what is on the horizontal and vertical axes and the underlying economic reasons for the shapes of the curves are very different. Long-term economic growth is illustrated in the AD/AS framework by a gradual shift of the aggregate supply curve to the right. A recession is illustrated when the intersection of AD and AS is substantially below potential GDP, while an expanding economy is illustrated when the intersection of AS and AD is near potential GDP.

24.5 How the AD/AS Model Incorporates Growth, Unemployment, and Inflation

Cyclical unemployment is relatively large in the AD/AS framework when the equilibrium is substantially below potential GDP. Cyclical unemployment is small in the AD/AS framework when the equilibrium is near potential GDP. The natural rate of unemployment, as determined by the labor market institutions of the economy, is built into what is meant by potential GDP, but does not otherwise appear in an AD/AS diagram. Pressures for inflation to rise or fall are shown in the AD/AS framework when the movement from one equilibrium to another causes the price level to rise or to fall. The balance of trade does not appear directly in the AD/AS diagram, but it appears indirectly in several ways. Increases in exports or declines in imports can cause shifts in AD. Changes in the price of key imported inputs to production, like oil, can cause shifts in AS. The AD/AS model is the key model used in this book to understand macroeconomic issues.

24.6 Keynes’ Law and Say’s Law in the AD/AS Model

The SRAS curve can be divided into three zones. Keynes’ law says demand creates its own supply, so that changes in aggregate demand cause changes in real GDP and employment. Keynes’ law can be shown on the horizontal Keynesian zone of the aggregate supply curve. The Keynesian zone occurs at the left of the SRAS curve where it is fairly flat, so movements in AD will affect output, but have little effect on the price level. Say’s law says supply creates its own demand. Changes in aggregate demand have no effect on real GDP and employment, only on the price level. Say’s law can be shown on the vertical neoclassical zone of the aggregate supply curve. The neoclassical zone occurs at the right of the SRAS curve where it is fairly vertical, and so movements in AD will affect the price level, but have little impact on output. The intermediate zone in the middle of the SRAS curve is upward-sloping, so a rise in AD will cause higher output and price level, while a fall in AD will lead to a lower output and price level.

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