Why are negative externalities important?

Why are negative externalities important?

Ever feel as if you are paying the price for someone else’s “deal”? Perhaps you are choking on the pollution from a foundry where cheap widgets are made. That spillover effect is called an externality. There are positive ones, too. Learn more about externalities in this episode of the Economic Lowdown Podcast Series.

Why are negative externalities important?
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Transcript

What do pollution, education, and your neighbor's dog have in common?

No, that's not a trick question. All three are actually examples of economic transactions that include externalities.

When markets are functioning well, all the costs and benefits of a transaction for a good or service are absorbed by the buyer and seller. For example, when you buy a doughnut at the store, it's reasonable to assume all the costs and benefits of the transaction are contained between the seller and you, the buyer. However, sometimes, costs or benefits may spill over to a third party not directly involved in the transaction. These spillover costs and benefits are called externalities. A negative externality occurs when a cost spills over. A positive externality occurs when a benefit spills over. So, externalities occur when some of the costs or benefits of a transaction fall on someone other than the producer or the consumer.

Negative Externalities

Imagine there's a factory in your town that produces widgets, a good that benefits consumers all over the world. The smokestacks at the factory, however, belch out pollution 24/7. From an economic perspective, the firm is shifting some of its cost of production to society. How? Well, in its production process the firm uses clean air-a resource it does not pay for-and returns polluted air to the atmosphere, which creates a potential health risk to anyone who breathes it. If the firm were paying the full cost of production, it would return clean air to the atmosphere. Instead, if society wants clean air, society must pay to clean it. So, in this case, pollution represents the shifting of some of the cost of production to society, a negative externality. And, because the firm isn't paying the full cost of producing widgets, the price charged for widgets is artificially low. Consumers will buy more widgets at the artificially low price than at a price that reflects their full production cost. So, ultimately, more widgets are produced than would be the case if all costs were included. And since more widgets are being produced, more air is being polluted.

Correcting Negative Externalities

Government can play a role in reducing negative externalities by taxing goods when their production generates spillover costs. This taxation effectively increases the cost of producing such goods. The higher cost, then, better reflects the true cost of production because it includes the spillover costs of, say, pollution. So, such taxation attempts to make the producer pay for the full cost of production. The use of such a tax is called internalizing the externality. For example, let's assume the cost of producing the widgets noted earlier is two dollars per unit, but an additional 20 cents per unit had been shifted to society as a negative externality in the form of dirty air. The government could place a 20 cent tax on each widget produced to ensure that the firm pays the actual cost of production-which is now two dollars and twenty cents, including the cost of the negative externality. As a result of the higher cost of production, the firm will reduce its production of widgets thus reducing the level of pollution.

Positive Externalities

When you complete high school, you'll reap the benefits of your education in the form of better job opportunities, higher productivity, and higher income. A technical degree or college education will further enhance those benefits. Although you might think you are the only one who benefits from your education, that isn't the case. The many benefits of your education spill over to society in general. In other words, you can generate positive externalities. For example, a well-educated society is more likely to make good decisions when electing leaders. Also, regions with a more-educated population tend to have lower crime rates. In addition, more education leads to higher worker productivity and higher living standards for society in general. Although education has many spillover benefits, providers of education do not receive all the revenue they would earn if the full benefits of the transaction were internalized. To state it differently, producers of education are not fully compensated for the benefits that spill over to society. As a result, producers of education will likely under produce education.

Encouraging Positive Externalities

Government can play a role in encouraging positive externalities by providing subsidies for goods or services that generate spillover benefits. A government subsidy is a payment that effectively lowers the cost of producing a given good or service. Such subsidies provide an incentive for firms to increase the production of goods that provide positive externalities. And, because the spillover benefits go to society, government subsidies are a way for society to share in the cost of generating positive externalities. After all, society pays the taxes that fund the subsidies. Regarding education, because the government subsidizes public education, a greater quantity of education is produced and consumed and society reaps the spillover benefits.

Which One Is It?

An externality is determined positive or negative based on whether costs or benefits spill over. Imagine this scenario: Your neighbor buys a dog, feeds the dog, and pays all of the expenses to care for the dog. In other words, your neighbor is bearing the explicit costs of dog ownership. Your neighbor also receives benefits from the dog, such as companionship and home security. But, what if the dog spends most of the night barking outside of your bedroom window, depriving you of valuable sleep? In this case, you would be bearing some of the costs of your neighbor's dog ownership-and that would be a negative externality for you. You could call your neighbor and try to reach an agreement. But, if that weren't successful, you might call the police, who may fine your neighbor. You could think of that as a type of corrective tax.

On the other hand, let's assume your neighbor's dog doesn't keep you awake at night. Instead, Fido is perfectly quiet and only barks when suspicious looking strangers come near your homes. Now the dog is providing you with the benefit of home security without you having to share in the cost of the dog-you receive a positive externality. You might choose to "subsidize" Fido by taking care of the dog when your neighbor is away or by giving the dog a treat from time to time.

To summarize, the costs and benefits of transactions for goods and services are often contained between the producers and consumers, but sometimes costs and benefits spill over to third parties. A negative externality exists when a cost spills over to a third party. A positive externality exists when a benefit spills over to a third-party. Government can discourage negative externalities by taxing goods and services that generate spillover costs. Government can encourage positive externalities by subsidizing goods and services that generate spillover benefits.

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  • Negative externalities occur when the consumption or production of a good causes a harmful effect to a third party.
  • Loud music. If you play loud music at night, your neighbour may not be able to sleep.
  • Pollution. If you produce chemicals and cause pollution as a side effect, then local fishermen will not be able to catch fish. This loss of income will be the negative externality.
  • Congestion. If you drive a car, it creates air pollution and contributes to congestion. These are both external costs imposed on other people who live in the city.
  • Building a new road. If you build a new road, the external cost is the loss of a beautiful landscape which people can no longer enjoy.

Why are negative externalities important?

  • The personal cost of driving are buying car, petrol, your time
  • The negative externalities are – pollution to other people, possible accident to other other people, and time other people sit in traffic jams

Social cost

  • Social cost is the total cost to society; it includes both private and external costs.
  • With a negative externality the Social Cost > Private Cost

Negative production  externality

  • When producing a good causes a harmful effect to a third party. Therefore the social cost is greater than the private cost.

Examples of negative production externalities

  • Burning coal for energy creates pollution.
  • Producing conventional vegetables with pesticides causes carcinogens to get into the environment.
  • Producing beef in South America involves cutting down Amazon rainforest, which has an impact on global climate and local environment

Why are negative externalities important?

  • Because of the external costs the social marginal cost is greater than the private marginal cost.
  • In a free market, producers ignore the external costs to others. Therefore output will be at Q1 (where Demand = Supply).
  • This is socially inefficient because at Q1 – SMC> SMB
  • Social efficiency occurs at Q2 where Social marginal cost = Social marginal benefit

The red triangle is the area of deadweight welfare loss. It indicates the area of overconsumption (where SMC is greater than PMC)

Negative externality of consumption

This occurs when consuming a good causes a harmful effect to a third party. In this case, the social benefit is less than the private benefit.

Examples of negative externalities of consumption

  • Consuming alcohol leads to an increase in drunkenness, increased risk of car accidents and social disorder.
  • Consuming loud music late at night keeps your neighbours awake.
  • Consuming cigarettes causes passive smoking to others in the vacinity.

Diagram of negative externality in consumption

Why are negative externalities important?
  • In a free market, we get Q1 output. But at this output, the social marginal cost is greater than the social marginal benefit.
  • The red triangle is the area of dead-weight welfare loss.
  • Social efficiency occurs at a lower output (Q2) – where social marginal benefit = social marginal cost.

Implications of negative externalities

If goods or services have negative externalities, then we will get market failure. This is because individuals fail to take into account the costs to other people.

To achieve a more socially efficient outcome, the government could try to tax the good with negative externalities. This means that consumers pay close to the full social cost.

Why are negative externalities important?

See: Tax on negative externalities

Economists on negative externalities

Arthur Pigou 1920 introduced the concept of externalities in The Economics of Welfare. Pigou used the example of alcohol having external costs, such as creating more demand for police and health care.

In 1975 William Baumol and W. Oates provided a comprehensive review of the literature on externalities in Theory of Environmental Policy. In particular, they applied economic concepts of externalities to the emerging issue of environmental costs. For example, in 1975, they mentioned some of the environmental costs which were considered to be pressing.

a. Disposal of toxic wastes,

b. Sulfur dioxide, particulates, and other contaminants of the atmosphere,

c. Various degradable and nondegradable wastes that pollute the world’s waterways,

d. Pesticides, which, through various routes, become imbedded in food products,

e. Deterioration of neighborhoods into slums,

f. Congestion along urban highways, g. High noise levels in metropolitan areas

Related

Last updated: 10th July 2019, Tejvan Pettinger, www.economicshelp.org, Oxford, UK