Transcript Consumer Surplus

EFISIENSI DAN EQUITY
MENU
Metode Alokasi Sumber Daya
 Demand, Willingness to Pay, and Value
 Individual Demand and Market Demand
 Consumer Surplus and Producer Surplus
 Kurva Lorentz dan Gini
 Equity and Equality
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PENDAHULUAN
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When making choices, people strive for
efficiency, trying to do the best they can
given their limited resources.
The notion of efficiency applies to all sorts
of decisions.
A household decides how much to spend on
consumer goods, how much to save, and
how much to spend on a college education.
The household tries to do the best it can
given its limited income.
As we ll see, economics provides a
framework to guide us from inefficient
choices to efficient ones.
DEFINISI
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EFISIENSI
A situation in which people do the best
they can, given their limited resources
(O’Sullivan et.all,2011).
The property of a resource allocation of
maximizing the total surplus received by
all members of society (Mankiw, 2011)
DEFINISI
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Pareto Efficiency or Pareto Optimality
A condition in which no change is
possible that will make some members of
society better off without making some
other members of society worse off.
When the net benefits of all
economic activities are maximized,
economists say the allocation of
resources is efficient
METODE ALOKASI
Because resources are scarce, some
mechanism must allocate them.
 Trading in markets is just one of several
alternative methods.
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METODE ALOKASI
The alternative allocation methods :
 market price;
 command;
 majority rule;
 contest;
 first-come, firstserved;
 lottery;
 personal characteristics;
 force.
Benefit, Cost, and Surplus
Resources are allocated efficiently and in
the social interest when they are used in the
ways that people value most highly.
 We’re now going to see whether
competitive markets produce the efficient
quantities.
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WILLINGNESS TO PAY
The maximum amount a consumer is
willing to pay for a product.
 The maximum amount that a buyer will
pay for a good.
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WILLINGNESS TO PAY
Imagine that you own a mint-condition recording of Elvis
Presley’s first album.
Because you are not an Elvis Presley fan, you decide to sell it.
One way to do so is to hold an auction.
WILLINGNESS TO PAY
Each buyer’s maximum is called his
willingness to pay, and it measures how
much that buyer values the good.
 Each buyer would be eager to buy the album
at a price less than his willingness to pay, and
he would refuse to buy the album at a price
greater than his willingness to pay.
 At a price equal to his willingness to pay, the
buyer would be indifferent about buying the
good: If the price is exactly the same as the
value he places on the album, he would be
equally happy buying it or keeping his money.
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Demand, Willingness to Pay,
and Value
In everyday life, we talk about “getting
value for money.
 ” When we use this expression, we are
distinguishing between value and price.
 Value is what we get, and price is what we
pay.
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Demand, Willingness to Pay,
and Value
The value of one more unit of a good or
service is its marginal benefit.
 We measure marginal benefit by the
maximum price that is willingly paid for
another unit of the good or service.
 But willingness to pay determines
demand.
 A demand curve is a marginal benefit curve.
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Demand, Willingness to Pay,
and Value
In Fig. 5.1(a), Lisa is willing to pay $1 for the 30th
slice of pizza and $1 is her marginal benefit from that
slice. In Fig. 5.1(b), Nick is willing to pay $1 for the
10th slice of pizza and $1 is his marginal benefit from
that slice
Individual Demand and Market
Demand
The relationship between the price of a
good and the quantity demanded by one
person is called individual demand.
 And the relationship between the price of a
good and the quantity demanded by all
buyers is called market demand.
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Individual Demand and Market
Demand
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The market demand curve is the horizontal
sum of the individual demand curves and is
formed by adding the quantities demanded
by all the individuals at each price
Figure 5.1(c) illustrates the market demand
for pizza if Lisa and Nick are the only people
in the market.
Lisa’s demand curve in part (a) and Nick’s
demand curve in part (b) sum horizontally
to the market demand curve in part (c).
Consumer Surplus
We don’t always have to pay as much as
we are willing to pay. We get a bargain.
 When people buy something for less than
it is worth to them, they receive a
consumer surplus.
 Consumer surplus is the excess of
the benefit received from a good over the
amount paid for it.
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Consumer Surplus
Consumer surplus is The amount a
buyer is willing to pay for a good minus
the amount the buyer actually pays for it.
 We can calculate consumer surplus as the
marginal benefit (or value) of a good
minus its price, summed over the quantity
bought.
 Consumer surplus = Value to buyers Amount paid by buyers.
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Consumer Surplus
Consumer Surplus
Individual Supply and Market
Supply
The relationship between the price of a
good and the quantity supplied by one
producer is called individual supply.
 And the relationship between the price of a
good and the quantity supplied by all
producers is called market supply.
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Individual Supply and Market
Supply
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The market supply curve is the horizontal
sum of the individual supply curves and is
formed by adding the quantities supplied
by all the producers at each price.
Producer Surplus
When price exceeds marginal cost, the
firm receives a producer surplus.
 Producer surplus is the excess of the
amount received from the sale of a good
or service over the cost of producing it.
 Producer surplus : the amount a seller is
paid for a good minus the seller’s cost of
providing it
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Producer Surplus
It is calculated as the price received minus
the marginal cost (or minimum supplyprice), summed over the quantity sold.
 Producer surplus = Amount received by
sellers - Cost to sellers.
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Cost and the Willingness to Sell
Imagine now that you are a homeowner and you want to get your
house painted.
You turn to four sellers of painting services: Mary, Frida, Georgia,
and Grandma.
Each painter is willing to do the work for you if the price is right.
You decide to take bids from the four painters and auction off the job
to the painter who will do the work for the lowest price.
Each painter is willing to take the job if the price she would receive
exceeds her cost of doing the work.
Producer Surplus
Producer Surplus
Equity
System of justice based on conscience
dan fairness
 Equality is the state of being equal
 Equality bagian dari equity
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Equality
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The property of distributing economic
prosperity uniformly among the members
of society
Tujuan Equity
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Parkin and colleagues identified two
objectives of equity:
a) The distribution of outcome or endstate is fair.
b) People have the same opportunities
even if the outcomes are unequal. This
allows differences in tastes, differences in
skills, and differences in diligence to
influence outcomes.
Equity or Equality
Membagi sama banyak (sama rata)
apakah salah??
 Alokasi subsidi
fairness
 Tujuan
outcome yang sama rata (equal
health status)
 Equity: variabel need, geografi,
sosioekonomi
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Equality adalah bagian dari equity
ex: equal access for equal need
 Equity : horisontal dan vertikal
 Equity : libertarian dan egalitarian
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Kurva Lorentz
Untuk mengetahui tingkat pemerataan
distribusi pendapatan suatu negara dapat
diketahui dari grafik yang dinamakan
Kurva Lorenz, artinya kurva yang
menggambarkan hubungan antara
distribusi jumlah penduduk dengan
distribusi pendapatan.
 The Lorenz curve provides a direct visual
clue about the degree of income
inequality by comparing it with the line of
equality (Parkin, 2011).
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Kurva Lorentz
The distribution of income in Fig. 19.1 and the quintile shares in Fig.
19.2 tell us that income is distributed unequally.
But we need a way of comparing the distribution of income in
different periods and using different measures.
A clever graphical tool called the Lorenz curve enables us to make such
comparisons.
Koefisien Gini
Sedangkan indikator untuk mengukur tingkat
ketimpangan distribusi pendapatan adalah
Koefisien Gini atau Indeks Gini.
 Semakin tinggi atau besar indeks gini, semakin
tinggi tingkat ketidakmerataannya (distribusi
pendapatannya tidak merata) dan semakin kecil
indeks gini semakin rendah tingkat
ketidakmerataannya (distribusi pendapatannya
semakin merata).
 Koefisien Gini mempunyai rentang 0 sampai 1. 0
merepresentasikan perfect equality dan 1 total
inequality.
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