IBDP Economics 2.8 Market failure—externalities and common pool or common access resources SL Paper 1 - New Syllabus

(a) Answer:

Common access resources, also called common pool resources, are resources that are generally non-excludable but rivalrous. Non-excludability means that it is difficult to prevent individuals from accessing the resource, while rivalry means that one person’s use reduces the amount available for others.

Because users cannot easily be excluded and it is difficult to charge an appropriate price for access, individuals have an incentive to use the resource whenever they can. Each individual considers mainly their own private benefit but does not fully consider the cost that their use imposes on other users.

This creates the tragedy of the commons. When many individuals independently pursue their own interests, the resource may be overused. For example, fishermen may have an incentive to catch as many fish as possible from a common fishing ground because restricting their own catch does not guarantee that another fisherman will do the same.

As fishing activity increases, the fish population may decline. The reduced stock imposes costs on other current and future users because fewer fish remain available. Since these external costs are not fully reflected in the market price, the resource may be consumed or exploited beyond the socially optimal level.

Common access resources can therefore lead to market failure, because the free market does not allocate the resource efficiently. Overuse can result in depletion, environmental damage and threats to the sustainability of the resource.

Examples include fisheries, groundwater reserves, forests and grazing land. In each case, unrestricted access can encourage excessive use because individual users have insufficient incentives to conserve the resource for others.

A negative externality diagram can be used to illustrate the divergence between the private and social costs of exploiting the resource. The market outcome may involve a quantity above the socially optimal level, resulting in a welfare loss from overuse.

Therefore, the combination of non-excludability and rivalry creates incentives for individuals to overuse common access resources. This can cause the tragedy of the commons, depletion of resources and an inefficient allocation of resources, representing market failure.

(b) Answer:

Demerit goods are goods whose consumption is considered harmful to consumers and/or society. They are often overconsumed because consumers may have imperfect information about the long-term consequences of consumption and because consumption can generate negative externalities.

An indirect tax is a tax imposed on spending on goods and services. A government can impose an indirect tax on a demerit good, such as cigarettes or alcohol, to increase its price and reduce the quantity consumed.

The tax increases firms’ costs and shifts the supply curve to the left/upward. The market price paid by consumers rises and the equilibrium quantity falls. This can reduce consumption and move the market closer to the socially desirable level.

Indirect taxation can also make consumers internalize some of the external costs associated with consumption. For example, a tax on cigarettes can reflect some of the wider healthcare and social costs associated with smoking.

Real-world example: The United Kingdom has imposed substantial tobacco duties to discourage smoking. Higher cigarette prices increase the financial cost of smoking and provide a direct incentive for consumers to reduce consumption. Such taxation has contributed to the long-term decline in smoking rates, although other factors such as education and public-health campaigns have also played a role.

Indirect taxes have an advantage over education because their effect does not depend entirely on consumers changing their knowledge or attitudes. Once a tax is imposed, the higher price directly changes the economic incentive to consume. Taxation can therefore be relatively easy to implement and can generate government revenue at the same time.

However, the effectiveness of an indirect tax depends heavily on the price elasticity of demand (PED). If demand for a demerit good is highly price inelastic, a substantial increase in price may result in only a small fall in quantity demanded.

This can occur because some demerit goods are addictive. For example, smokers who are heavily dependent on nicotine may continue buying cigarettes despite substantial increases in price. In this situation, taxation may raise government revenue considerably while having a relatively limited effect on consumption.

Indirect taxes can also be regressive. Lower-income households may spend a larger proportion of their income on certain demerit goods. A tax can therefore impose a proportionately greater financial burden on poorer consumers, creating an equity concern.

Another limitation is that the government may not know the exact monetary value of the negative externality. If the tax is set too low, consumption may remain above the socially optimal level. If it is set too high, consumption may fall below the socially desirable level and create an excessive burden on consumers.

Education provides a different approach. Government education campaigns can provide information about the health and social consequences of consuming demerit goods. By reducing imperfect information, education can cause consumers to make better-informed decisions and reduce consumption.

For example, governments have used anti-smoking campaigns to explain the health risks associated with smoking. Such campaigns can be particularly important for young people because changing attitudes before consumption becomes habitual may prevent future addiction.

Education can have a more lasting effect than taxation if it changes consumers’ preferences and understanding. Once consumers become aware of the risks of a demerit good, they may voluntarily reduce consumption even if its price remains unchanged.

However, education requires government expenditure and its effects may take considerable time to appear. Consumers may also ignore information or continue consuming a demerit good despite understanding its risks. This is particularly relevant where addiction is strong.

Education may therefore be more effective for younger consumers, while taxation may have a stronger immediate effect on current consumption. The relative effectiveness depends on the characteristics of the consumers and the good.

A combination of policies may therefore be more effective than relying exclusively on either taxation or education. For example, tobacco-control policies can combine higher tobacco taxes with health warnings, restrictions on advertising and public education campaigns. Taxation provides a direct price incentive, while education addresses imperfect information and can influence long-term behaviour.

Overall evaluation: Indirect taxes can be highly effective when demand is sufficiently price elastic because they immediately increase the cost of consumption and can also generate government revenue. However, their effectiveness is limited when demand is price inelastic, particularly for addictive goods, and they can be regressive.

Education is generally less effective in producing an immediate reduction in consumption because consumers may ignore information and behavioural change can take time. Nevertheless, it can address the underlying problem of imperfect information and may have stronger long-term effects, particularly among younger consumers.

Therefore, indirect taxes are not necessarily more effective than education in all circumstances. For highly addictive demerit goods with inelastic demand, taxation alone may have limited effects on consumption, whereas education can contribute to long-term behavioural change. The most effective approach is likely to depend on the PED of the good, the characteristics of consumers and the government’s ability to combine taxation with education and other measures.