User:TFarhan Azmi/Public good (economics)

Public good(economics) In economics, a public good (also referred to as a social good or collective good) is a good that is both non-excludable and non-rivalrous.

Terminology, and types of goods
Non-rivalrous: accessible by all whilst one's usage of the product does not affect the availability for subsequent use.

Non-excludability: it is impossible to exclude any individuals from consuming the good.

Pure public: when a good exhibits the two traits, non-rivalry and non-excludability, it is referred to as the pure public good.

Impure public goods: the goods that satisfy the two public good conditions (non-rivalry and non-excludability) only to a certain extent or only some of the time.

Private good: The opposite of a public good which does not possess these properties. A loaf of bread, for example, is a private good; its owner can exclude others from using it, and once it has been consumed, it cannot be used by others.

Common-pool resource: A good that is rivalrous but non-excludable. Such goods raise similar issues to public goods: the mirror to the public goods problem for this case is the 'tragedy of the commons'. For example, it is so difficult to enforce restrictions on deep-sea fishing that the world's fish stocks can be seen as a non-excludable resource, but one which is finite and diminishing.

Club goods: are the goods that excudable but are non-rivalrous such as private parks.

Definition matrix
{| class="wikitable"
 * Excludable
 * Non-excludable
 * Non-excludable

Definition matrix
Elinor Ostrom proposed additional modifications to the classification of goods to identify fundamental differences that affect the incentives facing individuals


 * 1) Replacing the term "rivalry of consumption" with "subtractability of use".
 * 2) Conceptualizing subtractability of use and excludability to vary from low to high rather than characterizing them as either present or absent.
 * 3) Overtly adding a very important fourth type of good—common-pool resources—that shares the attribute of subtractability with private goods and difficulty of exclusion with public goods. Forests, water systems, fisheries, and the global atmosphere are all common-pool resources of immense importance for the survival of humans on this earth.
 * 4) Changing the name of a "club" good to a "toll" good since many goods that share these characteristics are provided by small scale public as well as private associations.

Common examples of public goods include:

 * public fireworks
 * clean air and other environmental goods
 * information goods, such as official statistics
 * open-source software
 * authorship
 * public television
 * radio
 * invention