REV 00
PASARAN PERSAINGAN
SEMPURNA
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INTERMEDIATE ECONOMIC
1
REV 00
Objektif Pembelajaran
•
•
•
•
Di akhir kuliah, para pelajar diharap
akan dapat:
Memahami ciri-ciri PPS.
Teori pemaksimuman keuntungan.
Kecekapan dalam PPS.
Campur tangan kerajaan dalam pasaran.
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INTERMEDIATE ECONOMIC
2
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Ciri-ciri PPS
1. Penerima harga
– Firma individu menjual sebahagian kecil
sahaja dari keseluruhan penawaran dengan
itu tidak mampu mempengaruhi harga
pasaran.
– Semua firma akan menerima harga yang
sedia ada (penerima harga).
– Pengguna individu membeli bahagian kecil
sahaja dari keseluruhan permintaan dalam
industri dan tidak mampu mempengaruhi
harga pasaran.
3
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INTERMEDIATE ECONOMIC
REV 00
Ciri-ciri PPS
2. Barangan adalah Homogenik
– Semua barang ada pengganti hampir.
– Kualiti barang adalah hampir sama antara
satu sama lain.
– Cth barang: keluaran pertanian, minyak,
timah, besi & etc.
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INTERMEDIATE ECONOMIC
4
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Ciri-ciri PPS
3. Tiada bayaran keluar/masuk industri
– Tiada kos untuk masuk / keluar dari industri.
– Pembeli dengan mudah bertukar dari
seorang pembekal kepada pembekal lain.
– Pembekal mudah keluar/masuk pasaran.
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INTERMEDIATE ECONOMIC
5
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Pemaksimuman Keuntungan
– Keuntungan () = Jumlah hasil - Jumlah Kos
– Jumlah hasil = P x Q
– Jumlah kos = Kos seunit x Q
  R C
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INTERMEDIATE ECONOMIC
6
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Hasil Marginal & Kos Marginal
• Slope in revenue curve is the marginal
revenue
– Change in revenue resulting from a one-unit
increase in output
• Slope of total cost curve is marginal cost
– Additional cost of producing an additional unit
of output
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INTERMEDIATE ECONOMIC
7
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Profit Maximization - Short-Run
Cost,
Revenue,
Profit
($s per
year)
Untung maksimum berlaku apabila
MR (titik A) and MC (titik B) adalah
sama
C(q)
A
R(q)
Profits are
maximized
where R(q) –
C(q) is
maximized
B
0
q0
q*
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INTERMEDIATE ECONOMIC
Output
(q)
8
REV 00
Untung Maksimum
Jumlah keuntungan tertinggi yang boleh
dicapai oleh firma dalam kekangan
tertentu.
  R C
 R C


0
q q q
 MR  MC  0
MR  MC
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INTERMEDIATE ECONOMIC
9
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Keluk Permintaan dan Hasil
Marginal
Price
$ per
bushel
Price
$ per
bushel
Firm
$4
d
Industry
$4
D
100
200
Output
(bushels)
DGG 2413
INTERMEDIATE ECONOMIC
100
Output
(millions
of bushels)
10
REV 00
The Competitive Firm
• Demand curve faced by an individual firm is
a horizontal line
– Firm’s sales have no effect on market price
• Demand curve faced by whole market is
downward sloping
– Shows amount of good all consumers will
purchase at different prices
MC  MR  P  AR
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INTERMEDIATE ECONOMIC
11
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Choosing Output: Short-Run
• The point where MR = MC, the profit
maximizing output is chosen
– MR=MC at quantity, q*, of 8
– At a quantity less than 8, MR>MC so more
profit can be gained by increasing output
– At a quantity greater than 8, MC>MR,
increasing output will decrease profits
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INTERMEDIATE ECONOMIC
12
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Competitive Firm
Price
MC
Lost Profit
for q1<q*
50
Lost Profit
for q2>q*
A
40
AR=MR=P
ATC
AVC
30
q1 : MR > MC
q2: MC > MR
q0: MC = MR
20
10
0
1
2
3
4
5
6
7
q1
8
q*
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INTERMEDIATE ECONOMIC
9
q2
10
11
Output
13
REV 00
Competitive Firm - Profit
Price
Total Profit =
ABCD
50
40
MC
A
D
AR=MR=P
ATC
Profit per
unit = PAC(q) = A
to B
30 C
Profits are
determined
by output
per unit
times
quantity
AVC
B
20
10
0
1
2
3
4
5
6
7
q1
8
q*
DGG 2413
INTERMEDIATE ECONOMIC
9
q2
10
11
Output
14
REV 00
Short-Run Production
• Keuntungan maksimum apabila MC = MR
– Jika P > ATC firma mengalami untung.
– Jika P < ATC firma menanggung rugi.
• Bila firma perlu menutup operasi?
– Jika AVC < P < ATC firma perlu meneruskan
operasi dalam jangka masa pendek. Ini
membolehkan firma menutup sebahagian kos
berubah dan semua kos tetap.
– Jika AVC > P < ATC firma patut tutup operasi
kerana tidak berupaya menutup kos tetapnya.
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INTERMEDIATE ECONOMIC
15
REV 00
Kerugian
MC
Price
ATC
Losses
B
C
P < ATC but
D
AVC so
firm will
continue to
produce in
short run
F
A
P = MR
AVC
E
q*
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INTERMEDIATE ECONOMIC
Output
16
REV 00
Penawaran Jangka Pendek
• Keluk penawaran menunjukkan kuantiti
output yang dijual pada setiap harga.
• Firma mengeluarkan output pada P= MC
– Firma berhenti beroperasi apabila P < AVC
• PPS keluk penawaran ialah sebahagian
keluk MC di atas keluk AVC.
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INTERMEDIATE ECONOMIC
17
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• Firm will produce Q* as long as P>AVC.
MC
$
MR
ATC
P
Untung lebih
normal
Economic
profit
Q
Q*
MC
$
Normal profit
or break even
ATC
Untung normal
P
MR
Q
Q*
$
MC
ATC
Untung kurang
normal
MR
P
Q*
Economic loss
Q
18
REV 00
Keluk SS Firma Jangka Pendek
Price
($ per
unit)
The firm chooses the
output level where P = MR = MC,
as long as P > AVC.
Supply is MC
above AVC
MC
S
P2
ATC
P1
AVC
P = AVC
q1
DGG 2413
INTERMEDIATE ECONOMIC
q2 Output
19
REV 00
Firm’s Short-Run Supply Curve
• Supply is upward sloping due to
diminishing returns.
• Higher price compensates the firm for
higher cost of additional output and
increases total profit because it applies to
all units.
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INTERMEDIATE ECONOMIC
20
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Keluk Penawaran Pasaran Jangka
Pendek
• Shows the amount of product the whole
market will produce at given prices
• Is the sum of all the individual producers in
the market
• We can show graphically how we can sum
the supply curves of individual producers
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INTERMEDIATE ECONOMIC
21
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Penawaran Industri Jangka Pendek
MC1
$ per
unit
MC2
MC3
S
The short-run
industry supply curve
is the horizontal
summation of the supply
curves of the firms.
P3
P2
P1
Q
2
4 5
78
10
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INTERMEDIATE ECONOMIC
15
21
22
REV 00
Keluaran Jangka Panjang
• In the short run a firm faces a horizontal demand
curve
– Take market price as given
• The short-run average cost curve (SAC) and short
run marginal cost curve (SMC) are low enough for
firm to make positive profits (ABCD)
• The long run average cost curve (LRAC)
– Economies of scale to q2
– Diseconomies of scale after q2
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INTERMEDIATE ECONOMIC
23
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Output Choice in the Long Run
In the long run, the plant size will be
increased and output increased to q3.
Long-run profit, EFGD > short run
profit ABCD.
Price
LMC
LAC
SMC
SAC
$40
D
A
P = MR
C
B
G
$30
F
q1
q2
DGG 2413
INTERMEDIATE ECONOMIC
q3
Output
24
REV 00
Keseimbangan Jangka Panjang
• Accounting profit
– Difference between firm’s revenues and direct
costs
• Economic profit
– Difference between firm’s revenues and direct
and indirect costs
– Takes into account opportunity costs
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INTERMEDIATE ECONOMIC
25
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Long-run Equilibrium
• Firm uses labor (L) and capital (K) with
purchased capital
• Accounting Profit & Economic Profit
– Accounting profit:  = R - wL
– Economic profit:  = R = wL - rK
• wl = labor cost
• rk = opportunity cost of capital
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INTERMEDIATE ECONOMIC
26
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Long-run Equilibrium
• Zero Economic Profits
– If R > wL + rk, economic profits are positive
– If R = wL + rk, zero economic profits, but the
firms is earning a normal rate of return;
indicating the industry is competitive
– If R < wl + rk, consider going out of business
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INTERMEDIATE ECONOMIC
27
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Long-run Equilibrium
• Entry and Exit
– The long-run response to short-run profits is
to increase output and profits.
– Profits will attract other producers.
– More producers increase industry supply
which lowers the market price.
– This continues until there are no more profits
to be gained in the market – zero economic
profits
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INTERMEDIATE ECONOMIC
28
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Long-Run Equilibrium – Profits
$ per
unit of
output
•Profit attracts firms
•Supply increases until profit = 0
$ per
Firm
Industry
unit of
output
S1
LMC
$40
LAC
P1
S2
P2
$30
D
q2
Output
DGG 2413
INTERMEDIATE ECONOMIC
Q1
Q2
Output
29
REV 00
Long-Run Equilibrium – Losses
•Losses cause firms to leave
•Supply decreases until profit = 0
$ per
unit of
output
Firm
LMC
$ per
unit of
output
LAC
$30
Industry
S2
P2
S1
P1
$20
D
q2
Output
DGG 2413
INTERMEDIATE ECONOMIC
Q2
Q1
Output
30
REV 00
Long-Run Equilibrium
1. All firms in industry are maximizing profits
– MR = MC
2. No firm has incentive to enter or exit
industry
– Earning zero economic profits
3. Market is in equilibrium
– QD = QD
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INTERMEDIATE ECONOMIC
31
REV 00
Industry’s Long-Run Supply Curve
•
The shape of the long-run supply curve
depends on the extent to which changes in
industry output affect the prices the firms must
pay for inputs.
• To analyze long-run industry supply, will need
to distinguish between three different types of
industries
1. Constant-Cost
2. Increasing-Cost
3. Decreasing-Cost
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INTERMEDIATE ECONOMIC
32
REV 00
Constant-Cost Industry
$
Increase in demand increases
market price and firm output
Positive profits cause market
$
supply to increase and price to
fall
MC
Q1 increases to Q2.
Long-run supply = SL = LRAC.
Change in output has no impact
on
input cost.
S1
AC
P2
P2
P1
P1
S2
SL
D1
q1 q2
Output
DGG 2413
INTERMEDIATE ECONOMIC
Q1
Q2
D2
Output
33
REV 00
Increasing-Cost Industry
Long Run Supply is
upward Sloping
Due to the increase in input
prices, long-run equilibrium
occurs at a higher price.
SMC2
$
$
SMC1
LAC1
P2
S1 S2
LAC2
P2
P3
P3
P1
P1
D1
q1
q2
SL
Output
DGG 2413
INTERMEDIATE ECONOMIC
Q1 Q2 Q3
D2
Output
34
REV 00
Decreasing-Cost Industry
$
Due to the decrease
in input prices, long-run
equilibrium occurs at
a lower price.
SMC1
Long Run Supply is
Downward Sloping
$
S1
S2
SMCLAC
2
1
LAC2 P2
P2
P1
P1
P3
P3
SL
D1
q1 q 2
Output
DGG 2413
INTERMEDIATE ECONOMIC
Q1 Q2 Q3
D2
Output
35
REV 00
The Efficiency of a Competitive Market
 When do competitive markets generate an inefficient
allocation of resources or market failure?
1)
Externalities
 Costs or benefits that do not show up as part of the
market price (e.g. pollution)
2)
Lack of Information
 Imperfect information prevents consumers from making
utility-maximising decisions.
 Government intervention in these markets can increase
efficiency.
 Government intervention without a market failure creates
inefficiency or deadweight loss (kerugian luput).
36
REV 00
Minimum Prices
• Periodically government policy seeks to raise
prices above market-clearing levels.
• We will investigate this by looking at a price floor
and the minimum wage.
37
REV 00
Minimum Prices
If producers produce
Q2, the amount Q2 - Q3
will go unsold.
Price
S
The change in producer
surplus will be
A - C - D. Producers
may be worse off.
Pmin
A
B
C
P0
D
D
Q3
Q0
Q2
Quantity
38
REV 00
Harga Minimum
Firms are not allowed to
pay less than wmin. This
results in unemployment.
w
S
wmin
A
The deadweight loss
is given by
triangles B and C.
B
C
w0
Unemployment
L1
L0
D
L2
L
39
REV 00
Price Supports and Production Quotas
• Price Supports
– Much of agricultural policy is based on a system
of price supports.
– This is support price is set above the equilibrium
price and the government buys the surplus.
• This is often combined with incentives to reduce or
restrict production.
• Production Quotas
– The government can also cause the price of a
good to rise by reducing supply.
40