1. Efficiency and Exchange

2. The Domain of Markets Free markets promote efficiency
But, markets cannot be expected to solve every problem (e.g., market economies do not guarantee a fair income distribution)
Realizing that markets cannot solve every problem has led some critics to falsely conclude
that markets cannot solve any problem

3. Market Equilibrium and Efficiency
Pareto efficient (or just efficient)
Is a situation where there is no change possible that will help some people without harming others
Exists when an economy has reached a point where reallocating resources must harm one in order to help another
Occurs at equilibrium of perfectly competitive markets

4. Market Equilibrium and Efficiency
When a market is not in equilibrium:
P > P* = surplus -- QS > QD
2. P < P* = shortage -- QD > QS
In either case, the quantity exchanged is always LESS THAN the true equilibrium quantity.
Hence, if a market is not in equilibrium, further benefit-enhancing transactions are always possible.

5. Fig. 7.2 How Excess Demand Creates an Opportunity for a Surplus-Enhancing Transaction

6. Fig. 7.3 How Excess Supply Creates an Opportunity for a Surplus-Enhancing Transaction

7. Economic Surplus Total economic surplus
The sum of all the individual economic surpluses gained by buyers and sellers participating in the market
Consumer Surplus
Producer Surplus

8. Surplus Consumer Surplus Producer Surplus
Economic surplus gained by the buyers of a product
Measured by the difference between their reservation price and the price they pay
Producer Surplus
Economic surplus gained by the sellers of a product
Measured by the difference between the price they receive and their reservation price

9. Fig. 7.7 Total Economic Surplus in the Market for Milk

10. Surplus and Efficiency
Equilibrium price and quantity maximize the total economic surplus
Total economic surplus would be lower at any other price and quantity combination
I.E., “waste” or unrealized gain occurs at any other price and quantity combination

11. Other Goals Efficiency is not the only goal
An equitable income distribution is a desirable goal for many
Why efficiency should be the first Goal
Efficiency enables us to achieve all other goals to the fullest possible extent
Efficiency minimizes waste

12. The Costs of Price Controls
Price ceilings and price floors cause markets to be in permanent disequilibrium.
Price controls are therefore inefficient.

13. Price Ceilings Price Ceiling
It is a law or regulation that prevents sellers from charging more than a specified amount
It keeps price low
It reduces total economic surplus
It would allow some poor families to buy the good at the reduced price. [However, the same objective could have been accomplished with less waste.]

14. Fig. 7.8 Economic Surplus in an Unregulated Market for Home Heating Oil

15. Fig. 7.9 The Waste Caused by Price Controls

16. Fig. 7.10 When the Pie is Larger, Everyone Can Have a Bigger Slice

17. Price Floors Price Floor
It is a law or regulation that prevents buyers from paying less than a specified amount
It keeps prices high
It reduces total economic surplus
It would allow some poor families to buy the good at the reduced price. [However, the same objective could have been accomplished with less waste.]

18. Fig. 7.13 Equilibrium in an Unregulated Wheat Market

19. Fig. 7.14 Lost Surplus from Price Supports for Wheat

20. Taxes and Efficiency
What happens to the price of a good when the government imposes a tax on it?
Most people believe that the price of the item will rise by the amount of the tax
However, this may not be the case
Who pays the tax depends upon the elasticities of supply and demand

21. Taxes and Efficiency Who physically pays the tax?
The supplier of the taxed good is the one who sends the tax money to the gov’t. (Imagine if the consumer had to write a check to the gov’t for the gas tax each time they filled up).
So, the firm’s marginal cost of providing the good simply increases by the amount of the tax.
How would this affect supply and demand?

22. Fig. 7.16 The Effect of a $1 per unit Tax on the Equilibrium Quantity and Price of Potatoes

23. Taxes and Efficiency
Even though the vertical distance between the two supply curves is the amount of the tax, because of the relative slopes of the supply and demand curves, the consumer does not bear all of the tax burden.

24. Taxes and Efficiency Who will pay a larger percentage of the tax?
Whoever is less flexible with regard to price.
I.E. whoever is more inelastic
Consumers will pay 100% if:
Demand is perfectly inelastic
Supply is perfectly elastic

25. Fig. 7.17 The Effect of a Tax on Sellers of a Good with Infinite Price Elasticity of Supply

26. Taxes and Economic Surplus
“Deadweight loss” (DWL)
The reduction in economic surplus that results from a policy
A tax distorts the signal that free prices send

27. Fig. 7.18 The Market for Potatoes Without Taxes

28. Fig. 7.19 The Effect of a $1 Pound Tax on Potatoes

29. Fig. 7.20 The Deadweight Loss Caused by a Tax

30. DWL CS pre-tax = ½ (3)(3,000,000) = $4,500,000
PS pre-tax = ½ (3)(3,000,000) = $4,500,000
CS post-tax = ½ (2.50)(2,500,000) = $3,125,000
PS post-tax = ½ (2.50)(2,500,000) = $3,125,000
Lost PS+CS = $2,750,000
Tax revenue = $1(2,500,000) = $2,500,000
DWL = $250,000

31. Taxes, Elasticity, and Efficiency
Deadweight loss is minimized if taxes are imposed on goods and services that have relatively inelastic supply or relatively inelastic demand.

32. Fig. 7.21 Elasticity of Demand and the Deadweight Loss from a Tax

33. Fig. 7.22 Elasticity of Supply and the Deadweight Loss from a Tax

34. Do all taxes decrease economic efficiency?
Consider a tax on land
Land supply is perfectly inelastic
DWL = $0
What other goods have high tax rates?
Booze
Cigarettes
Gasoline

35. Taxes, External Costs, and Efficiency
Taxing reduces the equilibrium quantity
Therefore, taxing activities that people tend to pursue to excess can actually increase total economic surplus (e.g., activities that cause pollution)

36. External Costs
Consider a market activity that generates harmful side-effects on a 3rd party …
E.g. Pollution from a plant imposes costs on anyone who lives near the plant
Does that firm’s supply curve accurately reflect the full costs of production?
No. without regulation, the firm’s supply curve only reflects the marginal costs of production.
The external costs are not included in these costs.
What if they were?

37. Market Equilibrium CS + PS are maximized At P*MKT QD = QS = Q*MKT P
S = MPC
$20 = P*MKT
D = MSB
At P*MKT QD = QS = Q*MKT
CS + PS are maximized
Q*MKT Q

38. Market Equilibrium
The firm’s supply curve represents “private” or “market-level” marginal costs of production (MPC), and is used by the firm to make pricing and output decisions.
If there are external costs (costs realized outside of the market), the FULL costs of production would be represented by a different curve = MSC
For example, suppose that each unit of output causes $2 in damage to 3rd parties.

39. Social Equilibrium P MSC = MPC + 2 S = MPC D = MSB Q*SOC Q*MKT Q
$21 = P*SOC
$20 = P*MKT
D = MSB
Q*SOC Q*MKT Q

40. Social Efficiency At P*MKT: How can this inefficiency be corrected?
MSC > MSB
Q*MKT > Q*SOC the market “overproduces” the good
P*MKT < P*SOC the market “under-prices” the good
Market solution is therefore not efficient from society’s standpoint
How can this inefficiency be corrected?

41. Social Efficiency
A tax equal to the marginal external cost ($2.00) would serve to increase the firm’s MPC so that it is coincident with the MSC function.
In other words, the tax brings the external cost into the market.
= “internalizing the externality”

42. Social Equilibrium P New MPC = Old MPC + 2 S = MPC D = MSB
$21 = P*SOC
D = MSB
Q*SOC Q*MKT Q

43. Can markets create external benefits?
If markets can create costs on 3rd parties, can they create benefits?
Sure.
Education.
Lawn care
House maintenance
Text: beekeeper adjacent to apple orchard
Will the market solution be efficient?

44. External Benefits P
S = MSC
P*MKT
MSB
D = MPB
Q*MKT Q*SOC Q

45. External Benefits
In the case of external benefits, the market will under-provide the good relative to the socially optimal amount.
I.E. at Q*MKT MSB > MSC
How can this inefficiency be corrected?
Recall the solution to negative externality was a tax…
We should subsidize the positive externality generating activity.

46. Naturalist Questions
Why are gasoline taxes so high (relative to other goods)?
Why aren’t gasoline taxes higher (as in other nations)?
Why do communities have zoning laws?

47. Exercises
The more elastic demand is the ______ the burden of the tax borne by ______.
A. smaller; consumer and producers B. larger; consumers C. larger; producers D. smaller; producers E. larger; consumers and producers

48. Exercises
Which of the following statements expresses the justification for making efficiency the first goal of economic interaction?
A. Efficiency give the poor an incentive to improve their economic status. B. Since consensus on what is a fair distribution of goods is impossible, efficiency is the next best goal. C. People are not really concerned about the problems of the poor. D. It is too difficult to pursue more than one goal at a time. E. Efficiency maximizes total economic surplus and thereby allows other goals to be more fully achieved