A) Purpose of intervention with reference to market failure in various…

The idea

Government intervention aims to correct market failures where the free market fails to allocate resources efficiently, causing a net welfare loss. The primary purpose is to align private costs and benefits with social costs and benefits, achieving a socially optimum level of output. In contexts such as environmental pollution (negative externalities) or under-provision of education (positive externalities), intervention seeks to improve economic efficiency. For example, if a factory pollutes a river, the free market overproduces the good because it ignores the external cost. Intervention aims to internalise this externality, reducing output to the socially optimal level and eliminating the deadweight welfare loss.

What earns the marks

• Identify the specific type of market failure occurring in a given context, such as a negative externality or an information gap.
• Explain how the free market equilibrium diverges from the socially optimum equilibrium.
• State the purpose of intervention as correcting the misallocation of resources to improve social welfare.
• Analyse how intervention aims to internalise externalities or ensure the provision of public goods.

Common mistakes and how to put them right

• Confusing the purpose of intervention with the method of intervention.

  Put it right: The purpose is the overarching goal, such as correcting market failure, while the method is the specific tool used, such as taxation.

• Assuming government intervention always succeeds in its purpose.

  Put it right: Intervention can lead to government failure if the costs of intervention exceed the benefits or if it causes further market distortions.

• Stating that intervention aims to eliminate all pollution.

  Put it right: The purpose is usually to reduce pollution to the socially optimum level where marginal social cost equals marginal social benefit, not to zero.

Exam tips

• Always link the purpose of intervention back to the specific market failure identified in the stimulus material.
• Use precise economic terminology such as 'socially optimum output', 'welfare gain', and 'internalising externalities' when explaining the purpose.
• Be prepared to evaluate whether the intended purpose of an intervention is likely to be achieved in the given context.