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Principles of Microeconomics

Introduction to Demand and Supply

Principles of MicroeconomicsIntroduction to Demand and Supply
  1. Preface
  2. 1 Welcome to Economics!
    1. Introduction
    2. 1.1 What Economics Is and Why It's 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 International Trade
    1. Introduction to International Trade
    2. 19.1 Absolute and Comparative Advantage
    3. 19.2 What Happens When a Country Has an Absolute Advantage in All Goods
    4. 19.3 Intra-industry Trade between Similar Economies
    5. 19.4 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
  21. 20 Globalization and Protectionism
    1. Introduction to Globalization and Protectionism
    2. 20.1 Protectionism: An Indirect Subsidy from Consumers to Producers
    3. 20.2 International Trade and Its Effects on Jobs, Wages, and Working Conditions
    4. 20.3 Arguments in Support of Restricting Imports
    5. 20.4 How Trade Policy Is Enacted: Globally, Regionally, and Nationally
    6. 20.5 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
  22. A | The Use of Mathematics in Principles of Economics
  23. B | Indifference Curves
  24. C | Present Discounted Value
  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
  26. References
  27. Index
This is a photograph of various organic vegetables in baskets at a farmer's market.
Figure 3.1 Farmer’s Market Organic vegetables and fruits that are grown and sold within a specific geographical region should, in theory, cost less than conventional produce because the transportation costs are less. That is not, however, usually the case. (Credit: modification of work by Natalie Maynor/Flickr Creative Commons)

Bring It Home

Why Can We Not Get Enough of Organic?

Organic food is increasingly popular, not just in the United States, but worldwide. At one time, consumers had to go to specialty stores or farmer’s markets to find organic produce. Now it is available in most grocery stores. In short, organic is part of the mainstream.

Ever wonder why organic food costs more than conventional food? Why, say, does an organic Fuji apple cost $1.99 a pound, while its conventional counterpart costs $1.49 a pound? The same price relationship is true for just about every organic product on the market. If many organic foods are locally grown, would they not take less time to get to market and therefore be cheaper? What are the forces that keep those prices from coming down? Turns out those forces have a lot to do with this chapter’s topic: demand and supply.

Introduction to Demand and Supply

In this chapter, you will learn about:

  • Demand, Supply, and Equilibrium in Markets for Goods and Services
  • Shifts in Demand and Supply for Goods and Services
  • Changes in Equilibrium Price and Quantity: The Four-Step Process
  • Price Ceilings and Price Floors

An auction bidder pays thousands of dollars for a dress Whitney Houston wore. A collector spends a small fortune for a few drawings by John Lennon. People usually react to purchases like these in two ways: their jaw drops because they think these are high prices to pay for such goods or they think these are rare, desirable items and the amount paid seems right.

Link It Up

Visit this website to read a list of bizarre items that have been purchased for their ties to celebrities. These examples represent an interesting facet of demand and supply.

QR Code representing a URL

When economists talk about prices, they are less interested in making judgments than in gaining a practical understanding of what determines prices and why prices change. Consider a price most of us contend with weekly: that of a gallon of gas. Why was the average price of gasoline in the United States $3.71 per gallon in June 2014? Why did the price for gasoline fall sharply to $2.07 per gallon by January 2015? To explain these price movements, economists focus on the determinants of what gasoline buyers are willing to pay and what gasoline sellers are willing to accept.

As it turns out, the price of gasoline in June of any given year is nearly always higher than the price in January of that same year; over recent decades, gasoline prices in midsummer have averaged about 10 cents per gallon more than their midwinter low. The likely reason is that people drive more in the summer, and are also willing to pay more for gas, but that does not explain how steeply gas prices fell. Other factors were at work during those six months, such as increases in supply and decreases in the demand for crude oil.

This chapter introduces the economic model of demand and supply—one of the most powerful models in all of economics. The discussion here begins by examining how demand and supply determine the price and the quantity sold in markets for goods and services, and how changes in demand and supply lead to changes in prices and quantities.

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