Economics 9708/32 — May/June 2023

Background Concept

Asymmetric information occurs when one party in a transaction has more or better information than the other. This is a type of market failure because it prevents the market from allocating resources efficiently. In healthcare, the supplier (doctor/dentist) typically has superior knowledge about the patient's condition and the appropriate treatment, creating a situation of supplier-induced demand. This can lead to over-treatment, higher costs, and inefficient outcomes.

Understanding the Question

The question describes dentists replacing patients' teeth more often than necessary. It asks which economic factor explains this behaviour. The key is to recognise that the dentist knows more about the patient's dental health than the patient does, so the patient must trust the dentist's recommendations. This information asymmetry allows the dentist to recommend unnecessary procedures for personal gain.

Approach

Consider each option in turn:

• Asymmetric information (A) directly applies.
• Dynamic efficiency (B) is about long-run cost reduction and innovation, not relevant.
• Positive externalities (C) are spillover benefits; excessive treatment is a negative, not positive, for the patient.
• Social benefits (D) include private and external benefits; again not relevant. The correct answer is A.

Step-by-Step Reasoning

1. The dental treatment market features an imbalance of information: the dentist knows the true necessity of procedures; the patient does not.
2. This gives the dentist market power to recommend more treatment than needed, increasing their revenue (supplier-induced demand).
3. The patient cannot easily verify if the treatment is necessary, so they often follow the advice.
4. This behaviour represents a market failure because resources are wasted on unnecessary procedures, reducing both efficiency and patient welfare.
5. The other options do not explain this behaviour: dynamic efficiency refers to investment in new technology; positive externalities and social benefits are about beneficial spillovers to third parties.

Key Takeaways

• Asymmetric information is a common source of market failure, especially in professional services like healthcare, law, and finance.
• Supplier-induced demand arises when the provider has superior knowledge and can influence the quantity demanded.
• Recognising real-world examples of economic concepts is crucial for multiple-choice questions.

Common Mistakes

• Choosing 'positive externalities' because one might think that replacing teeth has benefits for others (e.g., appearance). However, the question specifies 'excessive' treatment, which imposes costs, not benefits.
• Confusing asymmetric information with moral hazard (which involves hidden actions after a transaction, not hidden knowledge before). Here it is hidden knowledge about the necessity.
• Overthinking: the scenario is a direct application of asymmetric information.

Things to Be Careful About

• Read the question exactly: 'excessive dental treatment' suggests a market failure, not an efficiency gain.
• Distinguish between different types of market failure: externalities, public goods, asymmetric information, etc.
• For exam questions, always link the concept directly to the scenario described.