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Principles of Macroeconomics 2e

Introduction to the Aggregate Supply–Aggregate Demand Model

Principles of Macroeconomics 2eIntroduction to the Aggregate Supply–Aggregate Demand Model
  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 To Organize Economies: 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 The Macroeconomic Perspective
    1. Introduction to the Macroeconomic Perspective
    2. 6.1 Measuring the Size of the Economy: Gross Domestic Product
    3. 6.2 Adjusting Nominal Values to Real Values
    4. 6.3 Tracking Real GDP over Time
    5. 6.4 Comparing GDP among Countries
    6. 6.5 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
  8. 7 Economic Growth
    1. Introduction to Economic Growth
    2. 7.1 The Relatively Recent Arrival of Economic Growth
    3. 7.2 Labor Productivity and Economic Growth
    4. 7.3 Components of Economic Growth
    5. 7.4 Economic Convergence
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  9. 8 Unemployment
    1. Introduction to Unemployment
    2. 8.1 How Economists Define and Compute Unemployment Rate
    3. 8.2 Patterns of Unemployment
    4. 8.3 What Causes Changes in Unemployment over the Short Run
    5. 8.4 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
  10. 9 Inflation
    1. Introduction to Inflation
    2. 9.1 Tracking Inflation
    3. 9.2 How to Measure Changes in the Cost of Living
    4. 9.3 How the U.S. and Other Countries Experience Inflation
    5. 9.4 The Confusion Over Inflation
    6. 9.5 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
  11. 10 The International Trade and Capital Flows
    1. Introduction to the International Trade and Capital Flows
    2. 10.1 Measuring Trade Balances
    3. 10.2 Trade Balances in Historical and International Context
    4. 10.3 Trade Balances and Flows of Financial Capital
    5. 10.4 The National Saving and Investment Identity
    6. 10.5 The Pros and Cons of Trade Deficits and Surpluses
    7. 10.6 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
  12. 11 The Aggregate Demand/Aggregate Supply Model
    1. Introduction to the Aggregate Supply–Aggregate Demand Model
    2. 11.1 Macroeconomic Perspectives on Demand and Supply
    3. 11.2 Building a Model of Aggregate Demand and Aggregate Supply
    4. 11.3 Shifts in Aggregate Supply
    5. 11.4 Shifts in Aggregate Demand
    6. 11.5 How the AD/AS Model Incorporates Growth, Unemployment, and Inflation
    7. 11.6 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
  13. 12 The Keynesian Perspective
    1. Introduction to the Keynesian Perspective
    2. 12.1 Aggregate Demand in Keynesian Analysis
    3. 12.2 The Building Blocks of Keynesian Analysis
    4. 12.3 The Phillips Curve
    5. 12.4 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
  14. 13 The Neoclassical Perspective
    1. Introduction to the Neoclassical Perspective
    2. 13.1 The Building Blocks of Neoclassical Analysis
    3. 13.2 The Policy Implications of the Neoclassical Perspective
    4. 13.3 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
  15. 14 Money and Banking
    1. Introduction to Money and Banking
    2. 14.1 Defining Money by Its Functions
    3. 14.2 Measuring Money: Currency, M1, and M2
    4. 14.3 The Role of Banks
    5. 14.4 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
  16. 15 Monetary Policy and Bank Regulation
    1. Introduction to Monetary Policy and Bank Regulation
    2. 15.1 The Federal Reserve Banking System and Central Banks
    3. 15.2 Bank Regulation
    4. 15.3 How a Central Bank Executes Monetary Policy
    5. 15.4 Monetary Policy and Economic Outcomes
    6. 15.5 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
  17. 16 Exchange Rates and International Capital Flows
    1. Introduction to Exchange Rates and International Capital Flows
    2. 16.1 How the Foreign Exchange Market Works
    3. 16.2 Demand and Supply Shifts in Foreign Exchange Markets
    4. 16.3 Macroeconomic Effects of Exchange Rates
    5. 16.4 Exchange Rate Policies
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  18. 17 Government Budgets and Fiscal Policy
    1. Introduction to Government Budgets and Fiscal Policy
    2. 17.1 Government Spending
    3. 17.2 Taxation
    4. 17.3 Federal Deficits and the National Debt
    5. 17.4 Using Fiscal Policy to Fight Recession, Unemployment, and Inflation
    6. 17.5 Automatic Stabilizers
    7. 17.6 Practical Problems with Discretionary Fiscal Policy
    8. 17.7 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
  19. 18 The Impacts of Government Borrowing
    1. Introduction to the Impacts of Government Borrowing
    2. 18.1 How Government Borrowing Affects Investment and the Trade Balance
    3. 18.2 Fiscal Policy and the Trade Balance
    4. 18.3 How Government Borrowing Affects Private Saving
    5. 18.4 Fiscal Policy, Investment, and Economic Growth
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  20. 19 Macroeconomic Policy Around the World
    1. Introduction to Macroeconomic Policy around the World
    2. 19.1 The Diversity of Countries and Economies across the World
    3. 19.2 Improving Countries’ Standards of Living
    4. 19.3 Causes of Unemployment around the World
    5. 19.4 Causes of Inflation in Various Countries and Regions
    6. 19.5 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
  21. 20 International Trade
    1. Introduction to International Trade
    2. 20.1 Absolute and Comparative Advantage
    3. 20.2 What Happens When a Country Has an Absolute Advantage in All Goods
    4. 20.3 Intra-industry Trade between Similar Economies
    5. 20.4 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
  22. 21 Globalization and Protectionism
    1. Introduction to Globalization and Protectionism
    2. 21.1 Protectionism: An Indirect Subsidy from Consumers to Producers
    3. 21.2 International Trade and Its Effects on Jobs, Wages, and Working Conditions
    4. 21.3 Arguments in Support of Restricting Imports
    5. 21.4 How Governments Enact Trade Policy: Globally, Regionally, and Nationally
    6. 21.5 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
  23. A | The Use of Mathematics in Principles of Economics
  24. B | The Expenditure-Output Model
  25. 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
  26. References
  27. Index
In this chapter, you will learn about:
  • Macroeconomic Perspectives on Demand and Supply
  • Building a Model of Aggregate Demand and Aggregate Supply
  • Shifts in Aggregate Supply
  • Shifts in Aggregate Demand
  • How the AD/AS Model Incorporates Growth, Unemployment, and Inflation
  • Keynes’ Law and Say’s Law in the AD/AS Model
This photograph shows a new house under construction.
Figure 11.1 New Home Construction At the peak of the housing bubble, many people across the country were able to secure the loans necessary to build new houses. (Credit: modification of work by Tim Pierce/Flickr Creative Commons)

Bring It Home

From Housing Bubble to Housing Bust

The United States experienced rising home ownership rates for most of the last two decades. Between 1990 and 2006, the U.S. housing market grew. Homeownership rates grew from 64% to a high of over 69% between 2004 and 2005. For many people, this was a period in which they could either buy first homes or buy a larger and more expensive home. During this time mortgage values tripled. Housing became more accessible to Americans and was considered to be a safe financial investment. Figure 11.2 shows how new single family home sales peaked in 2005 at 107,000 units.

The figure shows that single family house sales were highest in 2005 (to over 12,000 thousand) before plummeting drastically. In 2014, housing sales were over 400 thousand.
Figure 11.2 New Single Family Houses Sold From the early 1990s up through 2005, the number of new single family houses sold rose steadily. In 2006, the number dropped dramatically and this dramatic decline continued through 2011. By 2014, the number of new houses sold had begun to climb back up, but the levels are still lower than those of 1990. (Source: U.S. Census Bureau)

The housing bubble began to show signs of bursting in 2005, as delinquency and late payments began to grow and an oversupply of new homes on the market became apparent. Dropping home values contributed to a decrease in the overall wealth of the household sector and caused homeowners to pull back on spending. Several mortgage lenders were forced to file for bankruptcy because homeowners were not making their payments, and by 2008 the problem had spread throughout the financial markets. Lenders clamped down on credit and the housing bubble burst. Financial markets were now in crisis and unable or unwilling to even extend credit to credit-worthy customers.

The housing bubble and the crisis in the financial markets were major contributors to the Great Recession that led to unemployment rates over 10% and falling GDP. While the United States is still recovering from the impact of the Great Recession, it has made substantial progress in restoring financial market stability through implementing aggressive fiscal and monetary policy.

The economic history of the United States is cyclical in nature with recessions and expansions. Some of these fluctuations are severe, such as the economic downturn that occurred during the Great Depression in the 1930s which lasted several years. Why does the economy grow at different rates in different years? What are the causes of the cyclical behavior of the economy? This chapter will introduce an important model, the aggregate demand–aggregate supply model, to begin our understanding of why economies expand and contract over time.

Introduction to the Aggregate Supply–Aggregate Demand Model

In this chapter, you will learn about:

  • Macroeconomic Perspectives on Demand and Supply
  • Building a Model of Aggregate Supply and Aggregate Demand
  • Shifts in Aggregate Supply
  • Shifts in Aggregate Demand
  • How the AS–AD Model Incorporates Growth, Unemployment, and Inflation
  • Keynes’ Law and Say’s Law in the AS–AD Model

A key part of macroeconomics is the use of models to analyze macro issues and problems. How is the rate of economic growth connected to changes in the unemployment rate? Is there a reason why unemployment and inflation seem to move in opposite directions: lower unemployment and higher inflation from 1997 to 2000, higher unemployment and lower inflation in the early 2000s, lower unemployment and higher inflation in the mid-2000s, and then higher unemployment and lower inflation in 2009? Why did the current account deficit rise so high, but then decline in 2009?

To analyze questions like these, we must move beyond discussing macroeconomic issues one at a time, and begin building economic models that will capture the relationships and interconnections between them. The next three chapters take up this task. This chapter introduces the macroeconomic model of aggregate supply and aggregate demand, how the two interact to reach a macroeconomic equilibrium, and how shifts in aggregate demand or aggregate supply will affect that equilibrium. This chapter also relates the model of aggregate supply and aggregate demand to the three goals of economic policy (growth, unemployment, and inflation), and provides a framework for thinking about many of the connections and tradeoffs between these goals. The chapter on The Keynesian Perspective focuses on the macroeconomy in the short run, where aggregate demand plays a crucial role. The chapter on The Neoclassical Perspective explores the macroeconomy in the long run, where aggregate supply plays a crucial role.

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