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DEMAND DAN ELASTISTAS DEMAND
 DEMAND
 WANTS,NEEDS
AND DEMAND
 FAKTOR-FAKTOR YANG MEMPENGARUHI
DEMAND
 ELASTISITAS DEMAND DAN PERUBAHANNYA
 To
demand something, you must:
• Want it
• Be able to afford it
• Have a definite plan to buy it (Wonderling,
2005)
 Wants
are the unlimited desires or wishes
that people have for goods and services.
 How many times have you thought that you
would like something ‘if only you could
afford it’ or ‘if it weren’t so expensive’?
 When we make choices, scarcity guarantees
that many – perhaps most – of our wants will
never be satisfied.
 Demand reflects our plans about which
wants to satisfy.
 Permintaan
adalah keinginan yang disertai
kemampuan untuk membeli barang dan jasa
pada tingkat harga dan waktu tertentu.
 The term ‘demand’ is used to describe the
amount of money purchasers are prepared to
pay for a commodity.
 Hal
1.
2.
3.
Penting dalam Permintaan:
Kuantitas yang diminta merupakan
kuantitas yang diinginkan
Keinginan konsumen disertai oleh
kemampuan serta kesediaan untuk membeli
(Permintaan efektif)
Kuantitas yang diminta dinyatakan dalam
satuan waktu
 The
law of demand states:
Other things remaining the same (Ceteris
Paribus), the higher the price of a good, the
smaller is the quantity demanded.
Price
Quantity
 Before
going any further, you need to
understand a critical distinction between
demand and quantity demanded.
 The term demand refers to the entire
relationship between the quantity demanded
and the price of a good, illustrated by the
demand curve and the demand schedule.
 The term quantity demanded refers to the
exact quantity demanded at a particular
price, or a particular point on a demand
curve.
 Demand
Schedule :
A table that shows the relationship between
the price of a good and the quantity
demanded
 Demand Curve :
A graph of the relationship between the
price of a good and the quantity demanded
 Another
way of looking at the demand curve is a
willingness-and-ability-to-pay curve that measures
marginal benefit.
 It tell us the highest price that someone is willing
and able to pay for the last unit bought.
 If a small quantity is available, the highest price
that someone is willing and able to pay for one
more unit is high.
 But as the quantity available increases, the
marginal benefit of each additional units falls and
the highest price offered falls along the demand
curve.
In Next Figure, if 9 million tapes are bought each
week, the highest price that someone is willing to pay
for the 9 millionth tape is 30 pence.
 But if only 2 million tapes are bought each week,
someone is willing to pay £1.50 for the last tape
bought.

 When
any factor that influences buying
plans, other than the price of the good,
there is a change in demand.
 Figure 2 illustrates one such change – an
increase in demand. When demand
increases, the demand curve shifts to the
right and the quantity demanded is
greater at each prices.
Price (£ per tape)
Figure 2: An increase in demand
E’
E
5
D’ Demand for tapes
D
4
(Walkman £30)
C’
C
3
B’
B
2
1
New demand schedule (Walkman
£30)
Demand for tapes
(Walkman £125)
1
2
3
A’
A
4
5
6
7
8
Price
(£/tape)
Quantity (millions
of tapes/week)
A’
1
7.8
B’
2
5.9
C’
3
4.7
D’
4
4.2
E’
5
3.8
Quantity (millions of tapes /week)
1 Prices of related goods
 The quantity of any goods and services that
consumers plan to buy depends in part on
the price of related goods and services.
There are two types: substitutes and
complements.
2 Income
 Other things remaining the same, when
income increases, consumers buy more of
most goods, and when income decreases,
they buy less of most goods .
 Goods for which demand increases as income
increases are called normal goods.
 Goods for which demand decreases when
income increases are called inferior goods.
3 Expected future prices
 If the price of a good is expected to rise in
the future, and if the good can be stored,
the opportunity cost of obtaining the good
for future use is lower now than it will be
when the price has increased.
 So people substitute over time. They buy
more of the good before the expected price
rise and the demand for the good increases
4 Population
 Demand also depends on the size and the age
structure of the population.
 Other things remaining the same, the larger
the population, the greater is the demand
for all goods and services, and the smaller
the population, the smaller is the demand
for all goods and services.
5 Preferences
 Preferences are an individual’s attitudes
towards and tastes for goods and services .
 Preferences are shaped by past experience,
genetic factors, advertising information,
religious beliefs, and other cultural and
social factors.

Changes in the factors that
influence buyers’ plans cause
either:
a movement along the demand curve, or
2. a shift of the demand curve
1.



If the price of a good changes but everything else
remains the same, there is a movement along the demand
curve.
For example, if the price of a tape changes from £ 3 to £
5, the result is a movement along the demand curve,
from point C to point E in figure 1.
The negative slope of the demand curve reveals that a
decrease in the price of a good or service increases the
quantity demanded – the law of demand


If the price of a good remains constant but some
other influence on buyers’ plans changes, there is
a change in demand for that good
Figure 2 illustrates such a shift




A point on the demand curve shows the
quantity demanded at a given price
A movement along the demand curve
shows a change in the quantity
demanded
The entire demand curve shows
demand
A shift of the demand curve shows a
change in demand
Effect of:
1. A health promotion program
Price (£)
2. Relocate the clinic to outside the city
Price level
p1
D2
D3
q1
D1
Quantity (# of check-ups)
ELASTISITAS
•
•
Apabila perubahan harga yang kecil menimbulkan
perubahan yang besar terhadap jumlah barang yang
diminta, maka dikatakan bahwa permintaan barang
tersebut bersifat sangat responsif terhadap harga,
atau permintaannya adalah elastis.
Elastisitas permintaan adalah ukuran kuantitatif yang
menunjukkan sampai dimana besarnya pengaruh
perubahan harga terhadap perubahan permintaan
(Sukirno, 1994).
Elastisitas Permintaan
•
Ukuran kuantitatif yang menunjukkan sampai dimana
besarnya pengaruh perubahan harga terhadap
perubahan permintaan
•
Dibedakan menjadi 3 :
1. Elastisitas permintaan harga
2. Elastisitas permintaan pendapatan,
3. Elastisitas permintaan silang.
Paling penting adalah elastisitas permintaan harga.
ELASTISITAS PERMINTAAN

Elastisitas harga permintaan adalah ukuran seberapa
besar perubahan jumlah barang yang diminta akibat
merespon perubahan harga barang tersebut.

Elastisitas harga permintaan merupakan persentase
perubahan jumlah barang yang diminta karena harga
berubah 1%.
Elastisitas harga permintaan =
Persentase perubahan kuantitas yang diminta
Persentase perubahan harga
Jenis-jenis Elastisitas Permintaan
1. Inelastis sempurna : Ed = 0
Berapa pun harga suatu barang, orang akan tetap membeli
jumlah yang dibutuhkan. Permintaan terhadap insulin adalah
salah satu contoh barang yang termasuk inelastis sempurna.
Insulin adalah barang yang sangat dibutuhkan oleh para
penderita diabetes berapa pun harganya karena insulin dapat
menjaga mereka tetap sehat (Wonderling et all, 2005).
D1
Price
0
D
Quantity
2. Elastisitas sempurna : Ed = ∞ (tak terhingga)
Perubahan harga sedikit saja menyebabkan
perubahan permintaan tak terbilang besarnya
(Rahardja dan Manurung, 2004).
Price
D
0
D1
Quantity
3. Elastisitas Uniter : Ed = 1
Setiap perubahan sebesar 1 % pada harga akan diikuti
perubahan sebesar 1 % pada permintaan. Contoh : pelayanan
rawat jalan (outpatient).
Price
D
D1
0
Quantity
4. Inelastis : Ed< 1
Perubahan harga tidak terlalu mempengaruhi
perubahan permintaan. Contoh : pelayanan gawat
darurat, roti, rokok
Price
D
D1
0
Quantity
5. Elastis : Ed > 1
Perubahan harga sedikit akan menyebabkan perubahan permintaan
dalam jumlah cukup banyak.
Contoh : pelayanan kesehatan (McPake and Normand, 2008),
pelayanan bedah kosmetik, anggur putih, daging segar.
.
Price
D
D1
0
Quantity
Faktor-Faktor yang Mempengaruhi Elastisitas
Permintaan
1.
Ketersediaan barang subsitusi
Elastis banyak memiliki barang pengganti (substitusi) (Wonderling, et
all, 2005)
2. Persentasi pendapatan yang akan dibelanjakan untuk membeli barang
tersebut
Rendah  kenaikan harga hanya mempengaruhi sedikit pada kuantitas
(makin inelastis demand terhadap barang tersebut)
Tinggi  kenaikan harga mempengaruhi cukup banyak pada kuantitas
(makin elastis demand terhadap barang tersebut)
(Wonderling, et all, 2005)
3. Jangka waktu analisis.
Elastis  makin lama waktu lama
Inelastis  makin pendek waktu analisis (Trisnantoro, 2004)
4. Barang kebutuhan pokok atau barang mewah
Menghitung Elastisitas Harga Permintaan
Elastisitas harga permintaan =

Persentase perubahan kuantitas yang diminta
Persentase perubahan harga
Contoh: Apabila harga es krim naik dari Rp2.000
menjadi Rp2.200 dan jumlah yang Anda beli turun dari
10 menjadi 8 buah, maka elastisitas demand dapat
dihitung sebagai berikut:
(8  10)
100
20%
10

 2
(2.200  2.000)
100 10%
2.000
Metode titik tengah: Cara yang lebih baik untuk
menghitung persentase perubahan dan elastisitas
Elastisitas harga permintaan =
Q / Qaverage
P / Paverage
Contoh: seperti contoh sebelumnya, maka dengan
menggunakan metode titik tengah dihitung sebagai
berikut:
(8  10)
22%
(10  8) / 2

 2.32
(2.200  2.000)
9.5%
(2.000  2.200) / 2
Apa arti elastisitas 2,32?
 Menunjukan setiap perubahan harga barang
X sebesar 1% akan mengubah jumlah barang
X yang diminta sebesar 2,32% dengan arah
negative (elastisitas permintaan).
 Jika harga barang X naik 1% maka jumlah
barang X yang diminta turun 2,32%, ceteris
paribus.

Menghitung Elastisitas Harga Permintaan
(100-50)
ED 
Price
$5
4
0
Demand
50
(4.00-5.00)
(100  50)/2
(4.00  5.00)/2
67 persen

 -3
-22 persen
100 Quantity
Demand: elastis
Total Revenue dan Elastisitas Harga Permintaan
Price
•Total revenue adalah jumlah yang
diterima oleh penjual karena
transaksi barang
•Dihitung sebagai harga dikalikan
kuantitas barang yang dijual.
•
$4
TR = P x Q
P
P × Q = $400
(revenue)
Demand
100
0
Quantity
Q
Copyright©2003 Southwestern/Thomson Learning
Elastisitas dan Total Revenue sepanjang
Kurva Demand Linier
Pada kurva demand yang inelastis,
kenaikan harga mendorong penurunan
kuantitas yang proporsinya lebih kecil.
Maka, total revenue meningkat.
 Sebaliknya, pada kurva demand yang
elastis, kenaikan harga membuat total
revenue menurun

Figure How Total Revenue Changes When Price Changes:
Inelastic Demand
Price
Price
… leads to an Increase in
total revenue from $100 to
$240
An Increase in price from $1
to $3 …
$3
Revenue = $240
$1
Demand
Revenue = $100
0
100
Quantity
Demand
0
80
Quantity
Copyright©2003 Southwestern/Thomson Learning
Figure How Total Revenue Changes When Price Changes: Elastic
Demand
Price
Price
… leads to an decrease in
total revenue from $200 to
$100
An Increase in price from $4
to $5 …
$5
$4
Demand
Demand
Revenue = $200
0
50
Revenue = $100
Quantity
0
20
Quantity
Copyright©2003 Southwestern/Thomson Learning