Consumer and Producer Surplus

CONSUMER AND PRODUCER SURPLUS

Economic Surplus

  • Analysis of how the allocation of resources affects economic well-being:

    • Consumer Surplus (CS)

    • Producer Surplus (PS)

    • Total Surplus

WILLINGNESS TO PAY AND CONSUMER SURPLUS

Willingness to Pay (WTP)

  • Definition: A buyer’s willingness to pay for a good is the maximum amount the buyer will pay for that good.

  • Importance: WTP measures the value a buyer places on a good.

  • Variation: WTP varies across individuals, influenced by personal preferences and income.

  • Graphical Representation:

    • The WTP curve resembles a staircase due to discrete pricing.

    • In a competitive market with many buyers, the WTP curve would appear more like a smooth demand curve.

CONSUMER SURPLUS (CS)

Definition and Calculation

  • Consumer surplus is defined as the difference between the maximum amount a buyer is willing to pay and the actual amount paid:

    • CS = WTP - P

  • Total consumer surplus is represented graphically as the area under the demand curve that is above the prevailing market price.

EXAMPLE: DEMAND CURVE FOR USED TEXTBOOKS

Data Visualization

  • Price Points:

    • $59, $45, $35, $25, $10

  • Quantity Sold:

    • 1, 2, 3, 4, 5

  • Buyers:

    • Aleisha, Brad, Claudia, Darren, Edwina

    • Note: Each buyer has a different WTP which can be plotted against prices to show consumer surplus.

Consumer Surplus in the Used Textbook Market

When the Price of a Used Textbook Is $30

  • Individual WTP and Surplus Calculations:

    • Aleisha:

    • WTP = $59

    • Price Paid = $30

    • Individual Consumer Surplus = 59 - 30 = 29

    • Brad:

    • WTP = $45

    • Price Paid = $30

    • Individual Consumer Surplus = 45 - 30 = 15

    • Claudia:

    • WTP = $35

    • Price Paid = $30

    • Individual Consumer Surplus = 35 - 30 = 5

    • Darren:

    • WTP = $25

    • Price Paid = $30

    • Individual Consumer Surplus = 25 - 30 = 0

    • Edwina:

    • WTP = $10

    • Price Paid = $30

    • Individual Consumer Surplus = 10 - 30 = 0

  • Total Consumer Surplus Calculation:

    • ext{Total} \, CS = 29 + 15 + 5 = 49

HOW CHANGING PRICES AFFECT CS

Price Reduction Effects

  • A fall in the price of a good increases consumer surplus through two mechanisms:

    • Gain to buyers who would have purchased at the higher price.

    • Persuasion of additional buyers enticed by the lower price.

CS AND A FALL IN THE PRICE OF USED TEXTBOOKS

Changes at New Price of $20

  • Visual Representation of Surplus Changes

  • Analysis of how decreased prices affect individual and total consumer surplus across all potential buyers.

HOW A HIGHER PRICE REDUCES CS

  • Graphical and Quantitative Analysis of Reduced Consumer Surplus when prices rise.

  • Consequence: Fewer buyers entering the market, leading to decreased overall consumer surplus.

PRODUCTION COSTS AND PRODUCER SURPLUS

Cost and Willingness to Sell

  • Definition of cost: The total value of resources a seller gives up to produce a good, including time.

  • Sellers are inclined to produce and sell a good only if the price received exceeds their production costs.

  • Willingness to Sell: Reflects the lowest price at which a seller will sell the good.

PRODUCER SURPLUS AND THE SUPPLY CURVE

  • Individual Producer Surplus: Net gain a seller receives from selling a good calculated as the difference between price received and seller's production cost.

  • Total Producer Surplus: The aggregate of all individual producer surpluses in a market.

THE SUPPLY CURVE FOR USED TEXTBOOKS

  • Visual and numerical depiction of potential sellers with varying costs:

    • Prices for sellers: Andrew ($5), Betty ($15), Carlos ($25), Donna ($35), Engelbert ($45)

    • This curve illustrates the willingness of sellers to supply at different prices.

PRODUCER SURPLUS WHEN THE PRICE OF A USED TEXTBOOK IS $30

  • Individual producer surplus calculations and total producer surplus breakdown when the price is fixed at $30:

    • Andrew: WTP = $30 → PS = 30 - 5 = 25

    • Betty: WTP = $30 → PS = 30 - 15 = 15

    • Carlos: WTP = $30 → PS = 30 - 25 = 5

    • Total Producer Surplus = 25 + 15 + 5 = 45

HOW A LOWER PRICE REDUCES PS

  • Analysis of the impact of price reductions on producer surplus, outlining how lower prices lead to decreased profitability for existing sellers.

TOTAL SURPLUS

Calculation of Total Surplus

  • Total Surplus is defined as:

    • Consumer Surplus (CS) = (value to buyers) – (amount paid by buyers)

    • Producer Surplus (PS) = (amount received by sellers) – (cost to sellers)

    • Total Surplus = CS + PS = total gains from trade in a market = (value to buyers) – (cost to sellers)

Visual Representation of Total Surplus

  • Market equilibrium representation with shaded areas indicating consumer surplus in blue and producer surplus in yellow, while total surplus is framed in red.

TOTAL SURPLUS AND EFFICIENCY

  • Definition of Efficient Resource Allocation: Maximal total surplus is reached when

    • Goods are consumed by buyers who place the highest value on them.

    • Goods are produced by producers with the lowest costs.

    • Redistribution of quantities would not enhance total surplus.

PRICE CEILING AND ECONOMIC SURPLUS

  • Price Ceiling: Imposed maximum price below equilibrium leads to:

    • Creation of shortages.

    • Potential reduction in producer surplus.

    • Possible temporary increase in consumer surplus, which may also decrease it.

    • Deadweight Loss (DWL) due to market interventions, manifested graphically as the “Harberger triangle” lost between original equilibrium and reduced quantity.

RENTAL MARKET WITH PRICE CEILING

  • Comparative graphs illustrating consumer surplus, producer surplus, and deadweight loss in markets without and with price ceilings, emphasizing quantity differences.

PRICE FLOOR AND ECONOMIC SURPLUS

  • Price Floor: Imposed minimum price above equilibrium leads to:

    • Creation of surpluses.

    • Reduction in consumer surplus.

    • Potential increase in producer surplus, but may also decrease it.

    • Also results in deadweight loss.

LABOUR MARKET WITH PRICE FLOOR

  • Similar to price ceilings, labor markets with price floors illustrate the dynamics of consumer and producer surplus as well as the deadweight loss through comparative analysis.

COURSE REVIEW

Review Questions

  1. What determines the demand curve?

  2. How is individual consumer surplus defined? What is total consumer surplus in a market?

  3. How does a rise in price affect consumer surplus? And a fall in price?

  4. What determines the supply curve?

  5. How is individual and total market producer surplus defined?

  6. What is total surplus?

  7. How does the economic surplus concept relate to efficiency?

EXERCISE QUESTION

Smalltown Massage Example:

  • Consumers and their willingness to pay:

    • Edward: $8; Francesca: $3; George: $9; Hanna: $6

  • Firms and their costs:

    • Alpha: $7; Bravo: $4; Charlie: $3; Delta: $5

  • Questions to consider:

    1. For efficiency, how many massages should be provided?

    2. Which firms and consumers should engage?

    3. What is the maximum total surplus?

MULTIPLE-CHOICE QUESTIONS

  1. Willingness to pay refers to:
    A. The maximum amount a consumer is willing to pay for a good or service.
    B. The minimum price a producer is willing to accept for a good.
    C. The equilibrium price in a market.
    D. The actual price paid by the consumer.

  2. Consumer surplus is defined as:
    A. The total amount spent by consumers in a market.
    B. The difference between the price consumers pay and the price producers receive.
    C. The difference between a consumer's willingness to pay and the actual price paid.
    D. The total revenue earned by producers in a market.

  3. If a consumer is willing to pay €50 for a product and the actual price is €40, the consumer surplus is:
    A. €10
    B. €40
    C. €50
    D. €90

  4. Producer surplus is the area:
    A. below the supply curve and above the price.
    B. below the demand curve and above the supply curve.
    C. below the demand curve and above the price.
    D. above the supply curve and below the price.

  5. Which will increase consumer surplus?
    A. An increase in the price of the good.
    B. A decrease in the price of the good.
    C. A decrease in the consumer’s willingness to pay.
    D. A decrease in the number of consumers in the market.

  6. Producer surplus can increase if:
    A. The market price of the good decreases.
    B. Production costs increase.
    C. The market price of the good increases.
    D. Consumers’ willingness to pay decreases.

  7. What does the area below the demand curve but above the price line represent in a market graph?
    A. Producer surplus
    B. Consumer surplus
    C. Total revenue
    D. Total cost

  8. Total surplus in a market is best described as:
    A. The sum of consumer surplus and producer surplus.
    B. The total revenue earned by producers.
    C. The total cost incurred by consumers and producers.
    D. The difference between demand and supply at equilibrium.

  9. What happens to total surplus with a price ceiling set below the equilibrium price?
    A. Total surplus increases.
    B. Total surplus remains unchanged.
    C. Total surplus decreases.
    D. Total surplus is unaffected by price controls.

  10. Suppose the price of a new bicycle is €300. Natalie values it at €400. Cost of production is €200. What is total surplus if Natalie purchases it?
    A. €100
    B. €200
    C. €300
    D. €400