most efficient allocation of resources is achieved
best available solution to the basic economic problem is achieved
why don't markets work perfectly
irrational behaviour
behavioural economics
computational weakness and anchoring
lack of information
lack of competition
inequality
misallocated resources from the point of view of society as a whole - externalities - partial market failure
missing/absent markets - public goods - complete market failure
externalities are a major cause of market failure and are likely in every market
externalities, spill-over effects from production and consumption
no appropriate compensation is paid/received
lie outside the initial market transaction/price
causes market failure if price mechanism doesn't take account of social costs and benefits of production and consumption
externalities can be positive and/or negative
negative production externalities
negative consumption externalities
positive production externalities
positive consumption externalities
private costs
costs faced by the producer or consumer directly involved in a transaction
private benefits
benefits for producer of consumer directly involved in an economic transaction
the existence of externalities creates a divergence between private and social costs of production and the private and social benefits of consumption
social cost = private cost + external cost
social benefit = private benefit + external benefit
when negative externalities exist, social costs exceed private cost
leads to over-production and market failure if producers do not take into account the externalities
when positive externalities occur, social benefits exceed private benefit - can lead to market failure
private and external costs and benefits on a graph
marginal social cost and benefit - MSC + MPB
negative externalities
exist when third parties are harmed by the spill-over effects from production or consumption
private costs
costs faced by the producer/consumer who is directly involved in the transaction
external costs
costs imposed on third parties who aren't directly involved in the transaction (externalities)
social costs = private costs + external costs
external costs damage third parties, but the consumer and producer don't have to pay, meaning that the output will be too high
in the case of negative production externalities, the market price will be too low
marginal private cost - MPC
cost to the firm of producing an additional unit of output
marginal external cost - MEC
cost to third parties from the production of an additional unit of output
marginal social cost - MSC
total cost to society of producing an extra unit of output
MSC = MPS + MEC
negative production externalities are generated and received in supplying a good or service and they often involve noise and atmospheric pollution e.g. pollution from factories, pollution from fertilisers, industrial waste, noise pollution from aircraft, collapsing fish stocks and methane emissions from cows
negative production externality
if MSC pivots away from MPC then the MEC of extra output is increasing, the equilibrium output delivered in the free market is allocatively inefficient assuming there's no externalities from consumption so MSB=MPB
social welfare loss
when drawing welfare triangle, put pencil on free market equilibrium and draw a vertical line in whichever direction you can create a triangle - triangle always creates an 'arrow' that points towards the desired socially optimal equilibrium
positive externalities exist when third parties benefit from the spill-over effects from production or consumption
e.g. social returns from investment in education, positive benefits from health care/medical research
private benefits
benefits enjoyed by the producer and/or consumer who is directly involved in the transaction
external benefits
benefits enjoyed by third parties who aren't directly involved in the transaction (externalities)
social benefits = private benefits + external benefits
external benefits are good for third parties, but the consumer and producer don't take this into account, meaning that output will be too low, and in the case of positive consumption externalities, the market price will be too high
marginal private benefit - MPB
benefit to consumer consuming additional unit of output
marginal external benefit - MEB
benefit to third parties from the consumption of an additional unit of output
marginal social benefit - MSB
total benefit to society of consuming an extra unit of output
MSB = MPB + MEB
with positive consumption externalities, marginal social benefit is higher than marginal private benefit
positive consumption externality
in a free market, there is under-consumption of the good/service
mixed externalities
negative production and positive consumption externalities
there are net social benefits from consuming and producing the product, the free market mechanism underprovides this product and leads to market failure
negative production + positive consumption externalities
there are net social costs from consuming and producing the product, the free market mechanism leads to an overproduction of this product, leads to market failure
shadow pricing
a means of estimating the effect of an externality by calculating a potential price of lost opportunities
e.g. the external cost of road congestion can be calculated by the number of hours lost by the average wage - 1m working hours lost x £12 average hourly wage = £12m
compensation
estimate the cost of 'putting right' an externality
e.g. include the cost of installing double glazing in houses affected by increased road noise from a new motorway - if 200 houses are affected each with £5,000 double glazing cost, increased road noise is estimated at £1m
revealed preference
how much people are willing to pay to avoid an externality
e.g. if 200 householders are willing to pay £2,000 each to avoid noise, the externality is valued at £0.4m
Market failure occurs when the market fails to allocate scarce resources efficiently, causing a loss in social welfare