microeconomics

ECN502: Introduction to Microeconomics

Topic 3: Efficiency and Equity

Lecture Outline

  • Analyze and interpret the connection between demand and marginal benefit as well as the concept of consumer surplus.

  • Contrast the conditions under which markets operate efficiently.

  • Categorize different sources of inefficiency prevalent in the economy.

  • Design and interpret the fundamental ideas of fairness and evaluate claims that markets may result in unfair outcomes.

Demand and Marginal Benefit

  • Value vs. Price:

    • Value: Represents what the buyer perceives they gain from a good or service.

    • Price: The actual amount the buyer is required to pay for a good or service.

  • Marginal Benefit: The value derived from the consumption of an additional unit of a good or service.

  • Consumers are likely to purchase an additional unit if its price is less than or equal to the perceived value they assign to it, expressed as:
    ext{If } P ext{ (Price)} ext{ } ext{ < or = } ext{ the Value }

  • A demand curve effectively acts as a marginal benefit curve, illustrating the relationship between price and quantity demanded.

Individual Demand and Market Demand

  • Market Demand Curve: Formed by horizontally summing individual demand curves, showing total demand at various price levels.

Consumer Surplus (CS)

  • Definition: The difference between what consumers are willing to pay for a good (Willingness to Pay, WTP) and what they actually pay (Price, P). It can be defined mathematically as:
    ext{Consumer Surplus (CS)} = ext{WTP} - P

  • Measurement: Represented by the area under the demand curve above the market price, extending to the quantity bought.

Example Calculation:

  • When calculating CS, you can use the formula for the area of a triangle:
    CS = rac{1}{2} imes b imes h
    where:

    • $b$ is the base (the quantity of goods: 10,000), and

    • $h$ is the height (difference between WTP and P: 20 - 10).

    • Example:
      CS = rac{1}{2} imes (10,000) imes (20 - 10) = 50,000

  • Impact of Price Changes:

    • CS varies based on the equilibrium price.

    • A lower equilibrium price increases consumer surplus.

    • Example: At a pizza market equilibrium price of $10, consumers buy 10,000 pizzas:

    • Total consumer spending = $100,000.

    • CS from purchases = $50,000.

    • If the price rises to $15, consumer surplus for the 5,000th pizza becomes $5.

Supply and Marginal Cost

  • Cost vs. Price:

    • Cost: What the seller must forgo to produce the good.

    • Price: What the seller receives from selling the good.

  • Marginal Cost: The cost incurred in producing an additional unit of a good or service.

  • Sellers choose to produce an additional unit if its price meets or exceeds its marginal cost, represented by:
    ext{If } ext{Price} ext{ } ext{≥ } ext{ Marginal Cost (MC)}

  • The supply curve corresponds to the marginal cost curve, indicating how quantity supplied changes with varying prices.

Individual Supply and Market Supply

  • A Market Supply Curve is created by horizontally summing the individual supply curves.

Producer Surplus (PS)

  • Definition: The difference between the selling price of a good and the marginal cost of producing it, aggregated over the quantity sold:
    ext{Producer Surplus (PS)} = ext{Price} - ext{Cost}

  • Measurement: Represented by the area below the price level and above the supply curve up to the quantity sold.

  • Example Calculation:
    PS = rac{1}{2} imes b imes h
    where:

    • Example from pizzas sold ($10,000$ units):

    • PS = rac{1}{2} imes (10,000) imes (10 - 2) = 40,000

  • Market price of $10 results in a producer surplus of $40,000 from 10,000 pizzas sold, with total revenue amounting to $100,000. Should the price drop, for example, to $6, PS would reduce to $10,000.

Market Efficiency

  • Definition of Market Efficiency:

    • Refers to how accurately market prices reflect all available information.

    • An efficient market rapidly adjusts prices in response to new information.

  • Although market efficiency presumes optimal resource allocation via price signals, it may conflict with broader societal goals such as fairness and sustainability.

Resource Allocation Methods

  • Types:

    • Market Price: Initially allocative for those willing and able to pay.

    • Command: Allocative through orders from authorities.

    • Majority Rule: Allocates based on majority voter preference.

    • Contest: Allocation through winning a competition.

    • First-come, first-served: Allocates to those who arrive first.

    • Lottery: Allocation via random selection.

    • Personal Characteristics: Allocates through subjective traits of individuals.

    • Force: Can effectively allocate resources but raises ethical considerations regarding equity.

Market Efficiency in Competitive Markets

  • A competitive market leads to an efficient allocation of resources when:

    • Quantity demanded equates to quantity supplied at equilibrium.

    • At this equilibrium, marginal benefit equals marginal cost, resulting in efficiency.

    • The total surplus, comprising both producer and consumer surplus, achieves its maximization under these conditions.

    • Each player acts on self-interest, inadvertently serving social interest as a byproduct.

Deadweight Loss (DWL)

  • Definition: Represents the total lost welfare that occurs when resources are not allocated efficiently, often stemming from underproduction or overproduction:

    • Generated when market inefficiencies cause either too little or too much production, affecting consumer and producer surplus negatively.

  • Example of Underproduction:

    • When reducing output leads to DWL calculated as:
      DWL = rac{1}{2} imes b imes h

    • Example:

    • If output is reduced to 5,000 pizzas, DWL = $25,000, determined from above equations.

  • Example of Overproduction:

    • Exceeding efficient production levels, such as producing 15,000 pizzas due to government subsidies, also results in DWL of $25,000 under similar conditions.

Sources of Market Inefficiencies

  • Market Failures include:

    • Monopoly, oligopoly, externalities, public goods, incomplete markets.

  • Imperfect Competition:

    • Consists of price rigidity, collusion, barriers to entry, product differentiation.

  • Information Inefficiencies:

    • Arise from incomplete information, search costs, and misinformation.

  • Government Failures:

    • Result from overregulation/underregulation, inefficient taxation, subsidy distortions, and price controls leading to shortages or surpluses.

  • Labor Market Inefficiencies:

    • Include unemployment, wage rigidity, skill mismatches.

  • Technological Inefficiencies:

    • Lead to innovation gaps, technological lock-in, and underutilized technology.

  • Transaction Costs and Behavioral Factors:

    • High transaction costs complicate efficiencies, compounded by behavioral issues like self-interest biases.

Market Fairness

  • Utilitarianism:

    • A moral theory proposing that actions are best judged by their outcomes which maximize overall happiness.

    • The guiding principle emphasizes actions yielding the greatest good for the majority.

    • Example: In policy decisions, favoring actions that benefit the majority even if it disadvantaged a minority might be justified.

  • Criticisms of Utilitarianism:

    • Justification of morally questionable practices.

    • Difficulty in quantitatively measuring happiness across individuals.

    • Potential neglect of individual rights in favor of general happiness.

Case Study in Fair Distribution of Water

  • Scenario: 200 bottles of water for 100 families post-drought requires a fair and efficient distribution method.

  • Fairness in Distribution:

    • Each family could receive an equal allocation of 2 bottles.

    • Families with special needs might be prioritized but the goal is to ensure all have access.

  • Efficiency in Distribution:

    • Establish a central distribution point and organized pick-up times to minimize confusion and ensure fair access.

    • Outcome: Achieving fair and efficient distribution alleviating chaos while meeting essential needs.

Conclusion of Topic 3

  • Tutorial preparation is advised based on the discussed concepts and case studies.