Title: Economic Efficiency
1Economic Efficiency
- Hall and Lieberman, 3rd edition, Thomson
South-Western, Chapter 14
2Part I Efficiency
- Government acts as a social planner, aiming to
improve the welfare of the people - Sharp disagreement about the role of the
government should play in our economic life - Widespread agreement that certain goods and
services should be provided by government - Such as general police protection, the court
system, and national defense - Much of this agreement is based on ideas about
economic efficiency
3The Meaning of Efficiency
- Economic efficiency is achieved when there is no
way to rearrange the production or allocation of
goods in a way that makes one person better off
without making anybody else worse off - An efficient economy is not necessarily a fair
economy - Economists put stress on efficiency rather than
fairness - Issues of fairness must be resolved politically
4Pareto Improvements
- Definition a trade in which both parties are
made better off, and no one is harmed - Named after Italian economist, Vilfredo Pareto
(1848-1923) - Economic efficiency achieved when every possible
Pareto improvement is exploited - Perfectly competitive markets tend to be
economically efficient, and - Well-functioning market economics tend to lie
close to the economically efficient end of the
spectrum
5Part II Consumer Surplus and Producer Surplus
- Reservation Price
- Supply Side Lowest price that would induce
someone to provide a product to the market - Demand Side Highest price that a consumer would
pay to acquire a product
6Figure 1 The Marginal Benefit From Guitar
Lessons
Flo
25
Joe
23
Flo (again)
21
Bo
19
Zoe
17
Demand
1
2
3
4
5
7Reinterpreting the Demand Curve
- Maximum price someone would be willing to pay for
each unit of good (Figure 1) - Tells us how much that unit is worth to the
person who buys it - In part, this is because consumers differ in
their incomes and tastes
8Reinterpreting the Demand Curve
- Figure 1
- For each individualvalue of additional lessons
declines as more lessons are taken - Height of market demand curve at any quantity
shows us valueto someoneof last unit of good
consumed
9Consumer Surplus
- Useful to measure the benefits consumers receive
from their economic activities - A buyers consumer surplus on a unit of a good is
- Difference between its value to buyer and what
buyer actually pays for the unit
10Figure 2 Consumer Surplus in a Small and Large
Market for Guitar Lessons
25
23
21
19
17
Demand
1
2
3
4
5
11Consumer Surplus
- Total consumer surplus enjoyed by all consumers
in a market is called market consumer surplus - Sum of consumer surplus on all units
- Market consumer surplus at any pricemeasured in
dollarsis total area under market demand curve
and above market price
12Figure 3 Consumer Surplus in a Small and Large
Market for Guitar Lessons
19
Market Price
Demand
4,000
13Figure 4 The Marginal Costs of Guitar Lessons
Supply
21
McCollum
19
Martin (again)
17
Gibson
15
Martin (again)
13
Martin
1
2
3
4
5
14Reinterpreting the Supply Curve
- The minimum price a seller must get in order to
supply that lesson (Figure 2) - Because offering lessons is costly to guitar
teachers, it take higher prices to get more
lessons - Why?
- Height of market supply curve at any quantity
shows additional costto some producerof each
unit of good supplied
15Producer Surplus
- An individual sellers producer surplus on a unit
of a good - Difference between what seller actually gets and
additional cost of providing it - Total producer surplus gained by all sellers in a
market is called market producer surplus - Aggregation of individual producer surplus in
market - Market producer surplus at any pricemeasured in
dollarsis total area above market supply curve
and below market price
16Figure 5 Producer Surplus From Selling Guitar
Lessons
Supply
21
19
17
15
13
1
2
3
4
5
17Figure 6 Producer Surplus From Selling Guitar
Lessons
Supply
Market Price
19
4,000
18Figure 6 Total Net Benefits -- Sum of Consumer
and Producer Surplus (Guitar Lessons Market
Example)
S
Equilibrium Price
19
D
4,000
19Part III. The Efficient Quantity of a Good
- Whenever demand curve is higher than supply
curve, value of last unit to consumer is greater
than its additional cost to some producer - Producing one more good is a Pareto improvement
- Not true when demand curve lies below supply curve
20The Efficient Quantity of a Good
- Efficient quantity the quantity at which all
Pareto improvements are exploitedis where the
demand curve and supply curve intersect - At this quantity, value of the last good produced
will be equal toor possibly a tiny bit greater
thanthe cost of providing it
21Figure 7 Efficiency In The Market For Guitar
Lessons
Flo
25
Supply
Joe
23
Flo
21
McCollum
19
Martin
Bo
17
Zoe
Gibson
15
Martin
13
Demand
Martin
1
5
2
3
4
22Perfect Competition and Efficiency The Total
Benefits View
- Each time we make a Pareto improvement in a
market - We make at least one party better off and make no
one else worse off - Therefore, a Pareto improvement will increase
total net benefits available in a market - Thus, we have a new way of viewing efficiency
- A market is efficient when sum of producer and
consumer surplus is maximized in that market
23Markets and Economic Efficiency
- In a market system, firms and consumers are
largely free to produce and consume as they wish,
without anyone orchestrating the process from
above - Can we expect such unsupervised trading to be
economically efficient? - Yesas long as trading takes place in perfectly
competitive markets
24Perfect Competition and Efficiency
- Important idea in economics perfect competition
delivers an efficient economy - where many buyers and sellers each try to do the
best for themselves - where total net benefits are maximized
- Adam Smith coined term invisible hand to
describe the force that leads a competitive
economy relentlessly and automatically toward
economic efficiency