.
D P
20
A
C B
10
100 Figure 24.1
Ef ficient Rationing
Q
q
N ≥ N
C (q ) <
∑ C (q i ) i
=
i =
q i
N
∑i
=
q i = q
q
N q
, ..., N
D P
p R = AC(Q R)
MC(Q)
AC(Q)
D
Q R Figure 24.2
Natural Monopoly: Single-Product Firm
Q
D P
AC(Q)
D
qmes Figure 24.3
q1
Single-Product Natural Monopoly
Q
P
AC 1
AC 2
p* D2
D3
D1
qmes Figure 24.4
q NM
2qmes
Natural Duopoly
Q
M M
Q = q , q , ..., q Q
N ≥
C q , q
M
, ..., q
N
<
M C q q q , , ..., ∑ i i i i
=
q i m
m = , , ..., M N m m i = , ..., N ∑i q i = q m = , , ..., M =
N
C (Q ) <
∑ C (Q i ) i
=
M i
Q = q , q , ..., q i
i =
i
, ..., N
i
∂ CMg j ∂ q i
∂
C (q , q ) ∂ q , q
≤
≤
C (q , q ) − C ( , q ) CMeI = q
CMeI (Q ) S = CMg (Q ) S S
> <
CMeI (Q )
C (q , q ) < C (q , ) + C ( , q )
C (q , ) + C ( , q ) − C (q , q ) S = C (q , q ) C
S c >
S c <
E
tQe
q2 q2e
A
B Q = q1, q2 Qe tQd q2 / q1
q2d
Qd C q1e Figure 24.8
q1d
q1
Multiproduct Cost Concepts Illustrated
D
P
D1
MC(Q) AC(Q)
MC 2 p2 p1 c*
D2
MC 1
qmes Figure 24.5
Natural Monopoly and Marginal Cost Pricing
Q
D P
AC I (Q) p1
p2 AC(Q) D2
D1
Q1 Figure 24.6
Holdup in a Growing Market
Q2
Q
P
D
pm
m π
DWL
AC(Q) = MC(Q)
c
p
D MR Qm Figure 24.7 Inef ficient Regulation
Qc
Q
