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Political: What are Public Goods?

In this video, Professor Jonathan Anomaly (Duke and UNC – Chapel Hill) discusses public goods, which are goods that are jointly consumed, so that they are available to everyone if they are available to anyone. Public goods often lead to unexploited gains from trade, and are frequently invoked to justify why we have a state to perform basic functions like defense, property adjudication, and the regulation of pollution.

Speaker: Dr. Jonathan Anomaly, Lecturer/Research Assistant Professor, Duke University and University of North Carolina at Chapel Hill.

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  • piceratops seed style avatar for user Abdul-Kareem Abdul-Rahman
    at , the question was asked, if wi-fi is a public good, why is it privately provided?

    i think it is because wifi as a product, per se, is easily made a private good: it is in essence excludable (in the sense that underlying any access by nonpaying consumers is the assumption that one has been given the right to access the service which can be revoked at low cost by the account owner), and therefore not really public in nature. This is even more the case if the wifi access is via a password which assumes that each individual user would need to know the password to access it, hence making it rival.

    But more importantly, if the 'product' is conceptualised as 'a society which can access information easily via wifi', then this is a public good, as the fact that a society can access information easily is good for all society (nonrival) and does not incur cost to enjoy it (nonexcludable). If this is what society wants, its provision privately (as this product is implemented via wifi) represents an economic inefficiency.

    Although this touches so far on whether wifi is a public good, I have not really answered the question of why public goods are provided privately.

    Firstly, the answer is that it is perfectly acceptable for public goods to be PROVIDED privately. It happens all the time. This is because often a public good is disguised in or provided via a vehicle of a private good, and so incentivising the latter's production by private providers.

    Take healthcare for instance.

    If the good is a 'healthy society' the good is public. Everyone can enjoy the benefits of such a society (nonrival), and it does not cost to enjoy it (nonexcludable). Conceptualised in this way, it makes sense that public funds are then used to purchase *or* finance this product as private funds would not incentivise its production (why would drs and other providers provide healthcare if they are not paid?) .

    But if the 'good' is conceptualised narrowly as healthcare per se, it can be viewed as a private good. Only one person can be treated by a particular provider at any one time (rival). Typically one needs to pay to access a healthcare service (excludable).

    Hence the first conceptualisation of this good is provided via what is apparently a private good. One can readily observe that healthcare is provided by private providers quite commonly worldwide, even if the notion that a healthy society is a public good is commonly held in societies.

    If you asked then why are public goods still FUNDED privately, then you can see that it is related to the extent that societies recognise and/or accepts whether a 'good' (healthy societies, for instance) really is a public good. If the society does not, then one can see how it easily translates that the payment of the private good (healthcare: that is the vehicle for the overarching public good), will mainly be provided by private funds (and so not being enough to purchase the wider public good of 'a healthy society').
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Video transcript

(intro music) Hi! My name's Jonny Anomaly, and I teach at Duke University and UNC Chapel Hill. Today, I'm going to talk about public goods. Consider the following case. In representative governments around the world, citizens are periodically called on to vote for parties or candidates. In large elections, many people choose not to vote. But among those who do vote, each faces the choice of how much time to spend gathering and processing information about the candidates. Since each person's vote is unlikely to make a difference to the outcome of an election, and everyone knows this, there's little benefit to voters of trying to overcome bias or increase general knowledge about the relevant issues. The expected benefits of gathering and processing information are diffuse, but the cost is concentrated on the individual who has forego other way of spending his time. In other words, informed voting is a public good in democratic societies. Goods are public when they exhibit two properties: nonrivalry and nonexcludability. Nonrivalry exists when one person's consumption of a good doesn't diminish other people's opportunities for consumption, and nonexcludability exists when nobody can be excluded from consuming a good once it is produced. Ordinary goods that we purchase in a market are private, in the sense that once we own them, we can do what please with them, within the limits of the law. For example, when i buy a surfboard, I could choose to ride it, keep it stored in my closet, or sell it to the highest bidder. But since public goods are available for everyone to consume, it is difficult to get people to voluntarily provide them or conserve them once they've been provided. When I cast an informed vote for a candidate, I make that candidate just a tiny bit more likely to win, but the legislative consequences of the candidate's victory are shared by all citizens and potentially people in other countries and future generations. Because, for many people, it is psychologically costly to invest energy engaging in serious research rather than idle gossip about the candidates and issues at stake in an election, the public good of informed, unbiased voters is undersupplied. They are two separate impediments to the voluntary provision of public goods: the free rider problem and the assurance problem. Free riders are people who seek the benefits of a good, but who try to avoid paying for it. Other people face the assurance problem, which occurs when people are willing to pay for a public good but are unsure that enough others will contribute to make their effort worthwhile. one way to solve the assurance problem is by introducing altruistic punishment, which occurs when people are permitted to punish free riders. The prospect of altruistic punishment can help increase contributions to public goods especially well for small groups in which people can bear retribution for being identified as a free rider. Assurance contracts are another way of producing local public goods. Consider Kickstarter, an internet company that allows people to contribute to an outcome that everybody in a group wants, but which doesn't collect contributions until enough people donate to reach the threshold needed to fund the good. For example, we might use Kickstarter to fund a tennis court at a park that many people in a neighborhood visit. Public goods that are global and intergenerational, though, are much more difficult to provide or preserve. Antibiotics are an example of a powerful drug whose efficacy declines as their use increases, especially when they're used at subtherapeutic doses or misused to treat infections that they lack the power to cure. Preserving the power of antibiotics to cure infections is a public good because effective antibiotics are a nonrival, nonexcludable resource whose benefits spill across borders and across generations. Assurance contracts are useless for cases like this, because the transaction costs associated with bargaining between billions of people are too high. So we need more subtle ways of preserving public goods like antibiotics. One way to approach the problem is to convert public goods into private goods by increasing the extent to which each consumer internalizes the benefits and costs of using antibiotics. For example, someone suggested that user fees should be applied to the consumption of antibiotics, with the revenue being used to fund basic science research that will stimulate the development of new vaccines, new kinds of antibiotics, and technology for diagnosing infections. It is worth distinguishing a related set of principles. The problems of producing public goods, solving collective action problems, and avoiding commons tragedies are often similar in structure, and many introductory textbooks diagram all three problems as prisoner's dilemmas. But this isn't quite right. In a true prisoner's dilemma, the non-cooperative action is always taken, since a prisoner's dilemma is defined as a non-cooperative game with a unique Pareto dominated Nash equilibrium. In other words, in a true prisoner's dilemma, cooperation is never the rational move. But in public goods games, rational people often contribute. I want to end with a question: if wifi is a public good, why is it being privately provided? Subtitles by the Amara.org community