What is common to the greatest number gets the least amount of care. Men pay most attention to what is their own; they care less for what is common; or at any rate they care for it only to the extent to which each is individually concerned. - Aristotle
The above quote by Aristotle represents the fundamental idea behind the tragedy of commons, a phenomenon that often occurs with the consumption of private goods. Follow along to understand the differences between private, public, and quasi-public goods and their implications.
What are public goods?
A public good possesses the following characteristics:
- Non-excludable: consumers can’t be excluded from using the product.
- Non-rival: if one person uses a public good, it does not reduce its availability for others to use.
Street lighting is an example of a public good. This is a service that all citizens get to enjoy no matter how much they pay in taxes. Additionally, if one person is using the street lights, it does not exclude others from using them.
Theoretically, it would be possible to provide public goods privately. However, if people decide not to pay, it leads to market failure, as it is impossible to exclude the ‘non-payers’ from using the public good. Further examples of public goods include national defence, public roads, motorways, and bridges.
A public good is both non-rival and non-excludable.
Private goods and public goods
To better understand what public goods are, let’s take a look at the definition of private goods.
Private goods
Private goods constitute the majority of goods there are. They have the following characteristics:
- Excludable: the owners of the good can prevent others from consuming it.
- Rival: when a consumer consumes a private good, they diminish the available quantity of that good to other consumers.
A house is an example of a private good. The house owner can exclude you from using or buying their house (the good is excludable).
An example of rivalry can be a bag of crisps. If you eat the last bag of crisps at home, your family couldn’t eat it and the available quantity of crisps decreases for them. In other words, the quantity you consumed diminished the amount available to others.
A private good - is both rival and excludable.
Pure public and quasi-public goods
Public goods can be differentiated into two categories: pure public goods and quasi-public goods.
A pure public good is a good that is fully non-rival and non-excludable.
National defence is a pure public good since it is impossible to exclude free-riders.
The majority of public goods, however, are quasi-public or non-pure public goods.
Quasi-public goods have characteristics of both private and public goods, including partial excludability and partial rivalry.
For these types of goods, certain methods can be implemented to exclude free-riders.
A government can put new tolls on a motorway to exclude free riders.
The market can provide these types of goods. However, taking into account the concept of non-rivalry, it can be beneficial to provide public goods for free in order to encourage as much consumption of them as possible.
In other words, if public and quasi-public goods don’t have capacity restraints, optimal consumption levels take place when they are provided for free.
Examples of public goods and the free-rider problem
Imagine if street lighting wasn’t a public good. In this case, a company would set up street lighting and charge people for using it in an attempt to make a profit. However, even if none or very few people ended up paying for street lighting services, the community would still enjoy all the benefits of having street lighting. This is known as the free-rider problem. The price mechanism fails if there are free riders, as consumers will not choose to pay for a good they can get for free.
The free-rider problem occurs when, due to the non-excludable nature of public goods, consumers decide to not pay for the good at all and 'free-ride' instead.
Free-riding minimises profits for the company, as it is not possible for them to exclude the non-payers from using the service whilst still providing it to paying customers. Removing street lighting from the non-payers will remove street lighting for everyone. As a result, there is no incentive to provide public goods privately through the market. This is the idea behind a missing market, which results in market failure.
Missing markets occur when there is no incentive to provide a good through the market due to the free-rider problem.
Additionally, it is complicated to set the correct prices for public goods, as it is difficult to know how much value they will create for consumers. Producers are likely to overvalue the benefits of public goods in order to increase prices and therefore their profits. Meanwhile, consumers tend to undervalue these benefits in order to receive lower prices. This results in market failure.
This is another reason why firms might be disincentivised to provide public goods, leading to market failure and resulting in governments having to provide public goods.
Public good and the tragedy of the commons
The tragedy of the commons is an economic concept that suggests that people will always act in their own self-interest and overconsume common resources. As a result, common resources are destroyed or depleted. We can explain a lot of the environmental market failure by applying the concept of the tragedy of the commons.
Let’s say that a large public lake is used by many locals and fishermen as a fishing destination. They use the resource because it’s free, public, and belongs to everyone. However, after a couple of years, the fishermen notice that they can barely catch any fish. The lake has become depleted of resources. This is because people were acting in their own interest and overconsuming the resource without making any effort to conserve the lake and the ecosystem within the lake. As a result, no one can use the lake anymore.
The importance of technological change for public goods
Recent technological advances make it possible for governments to charge prices on quasi-public goods.
License plate recognition and other new technological measures allow for governments and local transport authorities to charge motor vehicles for using roads. This was previously not possible due to the lack of technical means to do so.
This type of technology also allows the government to charge different prices during different hours of the day to disincentivise people from using their vehicles during rush hour. For example, when roads are not congested and thus non-rival, it is possible to charge drivers less than during rush hour when rivalry is high.
The answer to whether public goods could be provided privately is far from simple. Even though people might be willing to pay for certain public goods and willing to pay to avoid certain public 'bads', it is unlikely that we will ever get rid of the free-rider problem.
Public Goods - Key takeaways
- Public goods are non-excludable and non-rival.
- Private goods are excludable and rival.
- Theoretically, it would be possible to provide public goods privately. However, if people decide to not pay, it leads to market failure, as it is impossible to exclude the ‘non-payers’ from using the public good.
- Public goods lead to problems with free riders, who enjoy the good without paying for it.
- The free-rider problem occurs when, due to the non-excludable nature of public goods, consumers decide to not pay for the good at all and 'ride free' instead.
- Missing markets occur when there is no incentive to provide a good through the market due to the free-rider problem.
- It is complicated to set the correct prices for public goods, as it is difficult to know how much value they will create for consumers.
- The tragedy of the commons is an economic concept that suggests that people will always act in their own self-interest and overconsume common resources.
- Quasi-public goods can be provided by the market. However, it can be beneficial to provide public goods for free in order to encourage as much consumption as possible.
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