Externalities vs Negative Externalities vs Positive Externalities
Externalities: cost or benefit that arises from production or consumption that falls on someone other than the producer or consumer.
Negative Externalities: cost imposed on 3rd party - punished
-Production: common costs that arise from production (clothing production –> pollution)
-Consumption: common costs that arise from consumption (speakers–>noise pollution)
Positive Externalities: benefit created for 3rd party - promoted
-Production: uncommon benefits that arise from production (honey production –> pollination)
-Consumption: common benefits that arise from consumption (education –> knowledge)
What is MSC = MC + MEC
MSC - Marginal Social Cost
Sum cost per unit of production for all of society = Social Supply Curve
EQ: MC+MEB
MC - Marginal Private Cost
Private cost per unit of production borne by producers = Private Supply Curve
EQ: MSC-MEC
MEC - Marginal External Cost
Social cost per unit of production borne by others = Vertical distance b/w MSC & MC curves
EQ: MSC-MC
Given:
PVT Cost Curve: P=6.25Q+75
SOC Cost Curve: P=37.5Q+75
Demand (MSB) Curve: P=-25Q+200
[Draw Graph to Support Calculations]
4 Ways to Eliminate DWL created by Negative Externality?
Eliminate DWL = Increase PKT cost to SOC EQM so firm bears all costs
What curves does Negative vs Positive Externalities impact?
Negative Externalities: Cost/Supply Curves
Positive Externalities: Benefits/Demand Curves
Given:
PVT Benefit Curve: P=-0.667Q+20
SOC Benefit Curve: P=-1.733Q+51
Supply (MSC) Curve: P=1.33Q+5
What is Deadweight Loss in Externalities
Social cost at PVT market equilibrium
3 Ways to Eliminate DWL created by Positive Externality?
Eliminate DWL = Increase supply to SOC EQM so max benefit for society is reached
What is MSB = MB + MEB
MSB - Marginal Social Benefit
Sum of benefit per unit of consumption for all of society = Social Benefit Curve
EQ: MB+MEB
MB - Marginal Private Benefit
Private benefit per unit of consumption = Private Benefit Curve
EQ: MSB-MEB
MEB - Marginal External Benefit
Social benefit per unit of consumption for society = Vertical different b/w PKT & SOC curves
EQ: MSB-MB
Short Run vs Long Run
Short Run: time frame where at least 1 factor remains fixed & decisions are easily reversible
Long Run: all factors are changing, irreversible decisions that can incur sunk (unrecoverable) costs
-Each plant has own unique cost curves
TP vs MP vs AP, Explain + Draw Graphs
Describing Output:
Total Production - total output produced in a given period
- Law of Diminishing Returns: fixed capital for infinitely increasing labour means output eventually increases decreasingly
- Inverse of TC (Total Cost)
Marginal Production - change in total product that results from a one-unit increase in the quantity of labour employed
EQ: TP2-TP1 + Midpoint
- Inverse to (MC) Marginal Cost
Average Product - Output per unit of labour
EQ: TP/Q of Labour
- As long as MP>AP=AP rises
MP<AP=AP fall
AP max when MP=AP
- Inverse of (AVC) Average Variable Cost
Explain + Draw Total Cost
Total Cost = TFC +TVC = cost of all resources used
- Law of Diminishing returns, less & less product being produced for an infinitely growing labor means cost eventually increases increasingly
- Inverse of TP curve
Total Fixed Cost = TC @Q=0
- Cost of firm’s fixed inputs, does not change with output
- Shifts TVC up to become TP
Total Variable Cost = Q of Laborers x Wage/Income/Pay Rate
- Cost of firm’s variable inputs, changes with output
- Gives TC its shape
- Inverse to TP
MC + ATC + AFC + AVC
Marginal Cost = increase in total cost that results from a one-unit increase in total product
- MC Inverse relationship with marginal production MP
- MC will hit AVC & ATC at their mins
Average Total Cost = total cost per unit of output = AFC + AVC = TC/TP
Average Fixed Cost = total fixed cost per unit of output = TFC/TP = ATC-AVC
- Approaches 0 as fixed constant cost/infinitely growing output
Average Variable Cost = total variable cost per unit of output = TVC/TP = ATC-AVC
- Minimum hits MC faster than ATC as AFC consistently falls slowing ATC’s ability to increase at the same rate as AVC
2 Factors that Shifts Cost Curves + Draw
Draw + Explain Long Run Average Cost Curve LRAC
Long Run Average Cost Curve (LRAC): shows us which plant gives us lowest/minimises ATC for each output level
Ex. At 15 sweaters a day cost is around $7 each on
ATC2. Least-cost way of producing 15 sweaters is
use 2 knitting machines
The larger the plant, the greater the output when ATC is at a minimum = great output incurs relatively lower cost the larger the plant
Diminishing MP of Capital & Labour Returns: as TP rises at a decreasing rate as labour increases with a fixed capital
Economies of Scale/LRAC increasing: features of a firm’s technology that lead to falling long-run average as output increases
Diseconomies of Scale/LRAC decreasing: features of a firm’s technology that lead to rising long-run average as output increases
Constant Returns to Scale/LRAC constant: features of a firm’s technology that lead to constant long-run average as output increases
Minimum Efficient Scale/LRAC minimum: smallest quantity of output at which the long-run average cost reaches its lowest point
Perfect Competition - MKT + PKT Demand + TR Graphs
A market in which
- Many firms sell identical products, perfect substitutes, to many buyers
- No restrictions to entry into the industry
- Established firms have no advantages over new ones
- Sellers & buyers are well informed about prices
MKT is price maker, firms are price taker.
MKT Graph shows:
- Demand is not perfectly elastic as substitute goods exist in the mkt
PKT Graph shows:
- Each firm’s output is a perfect substitute
TR Graph shows:
- TR is linear
- MR=P
How to Find Maximizing Output P & Q?
MC = MR
or
TR-TC max difference
In the short run:
Draw graphs
Draw Graphs
Profit<0 = Economic Loss –> Firms exit MKT –> S falls P rises –> MR=P rises >ATC –> until P=ATC –> Profit = 0
What is the Temporary Shutdown Point + What is the Economic Loss + Draw Supply Curve
Shutdown Point (AVC = P): when firm is indifferent b/w producing & shutting down temporarily
- Economic Loss = TFC
Economic Loss = TFC + Q(AVC-P) = PQ-ATCQ
Firm supplies shutdown Q or nothing
2 Factors that Shift Demand + Process that Ensues [Draw Graphs]
D rises → Pmkt rises → πFirm rises incurring economic profit π>0
Firms enter → S rises → Pmkt falls → QFirm falls
Continues until π=0
Number of firms =Qmkt/QFirm increase
Pmkt rises → QFirm rises until Pmkt=ATCMIN, π=0, all firms use new technology
Long Run Market Supply Curve
As output changes…
Decreasing Cost Industry (External Economies) cost of production decreases, P & D decrease
Constant Cost Industry cost of production constant, P & D constant
Increasing Cost Industry (External Diseconomies) cost of production increases, P & D increase
Monopoly
No close substitutes = no competition
Barriers to entering the market: protects firm from potential competitors
3 Types of Barriers to Entry in a Monopoly Market