1.4.1 Government Intervention in Markets

Specification Coverage: Edexcel unit 1.4.1 - Government intervention in markets. Students should understand why governments intervene in mixed economies and be able to analyse taxation, subsidies, maximum and minimum prices, and other interventions used to correct market failure or achieve policy goals.

Reasons for Government Intervention

Governments intervene in mixed economies to:

  • Correct market failure: achieve a more socially efficient allocation of resources, for example by addressing externalities.
  • Earn government revenue: fund public services through taxes or the sale of licences.
  • Promote equity: reduce inequality and support poorer households.
  • Support firms: help key industries remain competitive globally.

Indirect Taxation

Purpose: to reduce consumption of demerit goods, reduce negative externalities, and raise revenue.

Types of Indirect Tax

  • Specific tax: a fixed amount per unit, causing a parallel shift of the supply curve.
  • Ad valorem tax: a percentage of price, causing the supply curve to pivot upward and diverge from the original.
Diagrams showing the impact of an indirect tax.
Figure 1: The impact of an indirect tax on a market, showing the shift in supply, the new equilibrium, and the government revenue generated.

Subsidies

Purpose: to increase consumption and production of merit goods, encourage positive externalities, and support producers.

Effect: a subsidy lowers costs for producers, shifting the supply curve to the right.

Diagrams showing the impact of a subsidy.
Figure 2: The impact of an subsidy on a market, showing the shift in supply, the new equilibrium, and the government revenue generated.

Maximum Prices

Purpose: to make essential goods and services, such as food or rent, more affordable for consumers.

Mechanism: a legal maximum price set below the equilibrium price.

Diagrams showing the impact of a maximum price.
Figure 3: The impact of a maximum price on a market, showing the shift in supply, the new equilibrium, and the government revenue generated.

Minimum Prices

Purpose: to guarantee income for producers, such as farmers, or to discourage consumption of demerit goods, such as through alcohol minimum pricing.

Mechanism: a legal minimum price set above the equilibrium price.

Diagrams showing the impact of a minimum price.
Figure 4: The impact of a minimum price on a market, showing the shift in supply, the new equilibrium, and the government revenue generated.

Other Intervention Methods

Tradeable pollution permits: a cap-and-trade system where firms can buy and sell permits to pollute, creating an incentive to reduce pollution.

State provision: the government directly supplies public goods, such as street lighting or defence, that the free market would not provide because of the free-rider problem.

Provision of information: helps correct information gaps and asymmetric information, for example through food labelling or consumer advice.

Regulation: laws and rules that limit harmful activities, such as emissions standards or health and safety laws, enforced by regulators through fines and penalties.

Exam Preparation

  • Understand the rationale for each type of intervention.
  • Draw, label, and analyse the four key diagrams: ad valorem tax, subsidy, maximum price, and minimum price.
  • Analyse consequences: always consider the impact on consumers, producers, the government, and society, including shortages, surpluses, welfare loss, revenue, and cost.
  • Evaluate effectiveness: for taxes and subsidies, consider PED. For maximum and minimum prices, discuss unintended consequences such as black markets or the cost of buying surpluses.
  • Link interventions to market failure: explain how a tax corrects a negative externality or how a subsidy corrects a positive externality.