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Table of Contents

  1. Topic pack - Microeconomics - introduction
  2. 1.1 Competitive Markets: Demand and Supply
  3. 1.1 Competitive Markets: Demand and Supply - notes
  4. 1.1 Competitive markets - questions
  5. 1.1 Competitive markets - simulations and activities
  6. 1.2 Elasticities
  7. 1.2 Elasticities - notes
  8. Section 1.2 Elasticities - questions
  9. Section 1.2 Elasticities - simulations and activities
  10. 1.3 Government intervention
  11. 1.3 Government Intervention - notes
  12. 1.3 Government intervention - questions
  13. 1.3 Government intervention - simulations and activities
  14. 1.4 Market failure
  15. 1.4 Market failure - notes
    1. The meaning of externalities
    2. Types of externalities
    3. How do externalities affect allocative efficiency?
    4. Negative externalities of production
    5. Negative externalities of consumption
    6. The economic theory of traffic congestion
    7. Demerit goods
    8. Government responses - demerit goods
    9. Possible government responses to externalities
    10. Direct government provision
    11. Extension of property rights
    12. Taxes and subsidies
    13. Tradeable pollution rights
    14. Regulation, legislation and direct controls
    15. Positive externalities of production
    16. Positive externalities of consumption
    17. Merit goods
    18. Why might merit goods be underprovided by the market?
    19. Government responses - merit goods
    20. Public goods
    21. Common access resources & sustainability
    22. The tragedy of the Commons
    23. Common access resources in practice
    24. Sustainability
    25. Threats to Sustainability
    26. The threat to sustainability from the use of fossil fuels
    27. The threat to sustainability from poverty
    28. Government responses to threats to sustainability
    29. Cap and Trade Schemes
    30. Promoting Clean Technologies
    31. The 'dirty side' of cleaner technologies
    32. International responses to threats to sustainability
    33. Asymmetric information
    34. Abuse of monopoly power
    35. Inequality
  16. Section 1.4 Market failure - questions
  17. Section 1.4 Market failure - simulations and activities
  18. 1.5 Theory of the firm
  19. 1.5 Theory of the firm - notes (HL only)
  20. Section 1.5 Theory of the firm - questions
  21. Section 1.5 Theory of the firm - simulations and activities
  22. Print View

The meaning of externalities

What are externalities?



Externalities are costs (negative externalities) or benefits (positive externalities), which are not reflected in free market prices. Externalities are sometimes referred to as 'by-products', 'spillover effects', 'neighbourhood effects' 'third-party effects' or 'side-effects', as the generator of the externality, either producers or consumers, or both, impose costs or benefits on others who are not responsible for initiating the effect.

car_dumpedThe key feature of an externality is that it is initiated and experienced, not through the operation of the price system, but outside the market.

Proponents of laissez-faire would argue that externalities particularly arise because of the absence of markets - as no markets exist for such things as clean air and seas, beautiful views or tranquillity, economic agents are not obliged to take them into account when formulating their production and consumption decisions, which are based on private costs and benefits i.e. those which are internal to themselves. Another way of putting this is to say individuals have no private property rights over such resources as the air, sea and rivers, and thus ignore them in making their production and consumption decisions.

Property rights refer to those laws and rules that establish rights relating to:

  • ownership of property;
  • access to property;
  • protection of property ownership;
  • the transfer of property.

Thus a firm may feel free to dump effluent into a river as the spoiling of the environment and the killing of fish is not a cost that it would directly have to bear. Those on the political left would be more likely to argue that such an externality would arise because of the market system which is based upon the private ownership of resources, with individuals acting in their own self interest and therefore not having to consider what is in the public interest i.e. the problem is due to an absence of communal property rights and of a system of planned production.