Date post: | 18-Jan-2018 |
Category: |
Documents |
Upload: | flora-gaines |
View: | 214 times |
Download: | 0 times |
Perfect Competition in the Long-Run
1
You are a wheat farmer. You learn that there is a more profit in making corn.
What do you do in the long run?
Copyright ACDC Leadership 2015
In the Long-run…•Firms will enter if there is profit•Firms will leave if there is loss•So, ALL firms break even, they make NO economic profit(No Economic Profit = Normal Profit)
•In long run equilibrium a perfectly competitive firm is EXTREMELY efficient.
2Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm(price taker)
$15 $15
Side-by-side graph for perfectly completive industry and firm in the LONG RUN
3
MR=D
ATC
MC
8
Is the firm making a profit or a loss? Why?
Copyright ACDC Leadership 2015
***Price = MC = Minimum ATC***Firm is making NO economic profit
Firm is making positive accounting profit
Firm in Long-Run Equilibrium
4
P
Q
$15
4
MR=D
ATC
MC
8
There is no incentive to enter or leave the
industryTC = TR
Copyright ACDC Leadership 2015
Going from Short-Runto Long-Run
5Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
6
MR=DATC
MC
8
1. Is this the short or the long run? Why?2. What will firms do in the long run?3. What happens to P and Q in the industry?4. What happens to P and Q in the firm?
6000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
7
MR=DATC
MC
8
S1
$10
Firms enter to earn profit so supply increases in the industry
Price decreases and quantity increases
6000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
8
MR=DATC
MC
8
Price falls for the firm because they are price takers.
Price decreases and quantity decreases
S1
$10 $10 MR1=D1
56000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
Industry Firm 9
ATC
MC
New Long Run Equilibrium at $10 PriceZero Economic Profit
S1
$10 $10 MR1=D1
56000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
10
MR=D
ATCMC
8
1. Is this the short or the long run? Why?2. What will firms do in the long run?3. What happens to P and Q in the industry?4. What happens to P and Q in the firm?
4000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
11
MR=D
MC
8
S1
$20
Firms leave to avoid losses so supply decreases in the industry
Price increases and quantity decreases
ATC
4000Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
12
MR=D
MC
8
S1
$20
Price increase for the firm because they are price takers.
Price increases and quantity increases
ATC
4000
MR1=D1
9
$20
Copyright ACDC Leadership 2015
P
Q
P
Q
D
Industry Firm 13
MCS1
$20
New Long Run Equilibrium at $20 PriceZero Economic Profit
ATC
4000
MR1=D1
9
$20
Copyright ACDC Leadership 2015
Going from Long-Run to Long-RunConstant Cost Industry- New firms entering the market does not increase the
costs for the firms already in the market.
14Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
15
MR=D
MC
8
Currently in Long-Run Equilibrium If demand increases, what happens in the short-run
and how does it return to the long run?
ATC
Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
16
MR=D
MC
8
D1
$20
Demand Increases The price increases and quantity increases
Profit is made in the short-run
ATCMR1=D1
9
$20
Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
17
MR=D
MC
8
D1
$20
Firms enter to earn profit so supply increases in the industry
Price Returns to $15
ATCMR1=D1
9
$20
7000
S1
Copyright ACDC Leadership 2015
P
Q
P
Q
D
Industry Firm
$15 $15
18
MR=D
MC
8
D1
Back to Long-Run EquilibriumThe only thing that changed from long-run to
long-run is quantity in the industry
ATC
7000
S1
Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
19
MR=D
MC
8
What if demand falls?If demand decreases, what happens in the short-
run and how does it return to the long run?
ATC
Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
20
MR=D
MC
8D1
$10
Demand Decreases The price decreases and quantity decreases
Loss is taken in the short-run
ATC
MR1=D1
7
$10
Copyright ACDC Leadership 2015
P
Q
P
Q5000
D
S
Industry Firm
$15 $15
21
MR=D
MC
8D1
$10
Firms exit to avoid losses so supply decreases in the industry
Price Returns to $15
ATC
MR1=D1
7
$10
S1
3000Copyright ACDC Leadership 2015
P
Q
P
QIndustry Firm
$15 $15
22
MR=D
MC
8D1
Back to Long-Run EquilibriumThe only thing that changed from long-run to
long-run is quantity in the industry
ATC
S1
3000Copyright ACDC Leadership 2015
Practice
23
24
2012 Multiple Choice #23
25
2012 Multiple Choice #38
27
2010 FRQ #1
Going from Long-Run to Long-RunIncreasing Cost Industry- New firms entering the market increase the costs for the firms already in the
market. (Only asked once on a FRQ- 2011 Form B)
29Copyright ACDC Leadership 2015
P
Q
P
Q
D
S
Industry Firm
$15 $15
30
MR=D
Currently in Long-Run Equilibrium If demand increases, what happens in the short-run
and how does it return to the long run?
Copyright ACDC Leadership 2015
ATCMC
P
Q
P
Q
D
S
Industry Firm
$15 $15
31
MR=D
D1
$25
INCREASING COST IndustryThe price increases and quantity increases
Profit is made in the short-run
ATC$25
Copyright ACDC Leadership 2015
MC
P
Q
P
Q
D
S
Industry Firm
$15 $15
32
MR=D
D1
$25 $25
Copyright ACDC Leadership 2015
Firms enter to earn profit but fight for resources causing costs to increase
Price Falls to $20
S1ATC
MC
$20
ATC1MC1
P
Q
P
QIndustry Firm 33
MR1
D1
Copyright ACDC Leadership 2015
Firms enter to earn profit but fight for resources causing costs to increase
Price Falls to $20
S1
$20
ATC1MC1
2008 Audit Exam
Efficiency
35Copyright ACDC Leadership 2015
•Perfect Competition forces producers to use limited resources to their fullest.•Inefficient firms have higher costs and are the first to leave the industry.•Perfectly competitive industries are extremely efficient
In general, efficiency is the optimal use of societies scarce resources
1. Productive Efficiency2. Allocative Efficiency
There are two kinds of efficiency:
36Copyright ACDC Leadership 2015
Productive Efficiency- Producing at the lowest possible cost (minimum amount of resources are being used)Graphically it is where price equals the
minimum ATCAllocative Efficiency- Producing at the amount most desired by society (allocating resources towards the products society wants)
Graphically it is where price equals marginal cost 37Copyright
ACDC Leadership 2015
Single Firm MarketPr
ice
Pric
eQuantity Quantity
0 0
Long-Run Equilibrium
P MR
D
S
QeQf
ATC
Productive Efficiency: Price = minimum ATCAllocative Efficiency: Price = MCPure competition has both in
its long-run equilibriumWhat about in the short run?
MCP=MC=MinimumATC (Normal Profit)
P
9-38
SummaryPerfectly competitive firms are allocatively and productively efficient in the long-run
In the short-run, they are always allocatively efficient, but they are not productively efficient.
40Copyright ACDC Leadership 2015