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Table of Contents

  1. Topic pack - Development economics - introduction
  2. 4.1 Economic development (notes)
  3. 4.1 Economic development (questions)
  4. 4.2 Measuring Economic Development (notes)
  5. 4.2 Measuring development (questions)
  6. 4.3 The role of domestic factors in economic development (notes)
    1. Domestic factors - introduction
    2. An introduction to Tanzania
    3. Education
    4. Primary, secondary or tertiary education?
    5. A dependent population
    6. Tanzanian database
    7. Exploring education in Tanzania - data
    8. Exploring education in Tanzania - Maua and Namyani (video)
    9. Exploring education in Tanzania - lost dreams
    10. Exploring education in Tanzania - reflection
    11. Exploring health in Tanzania - data
    12. Exploring health in Tanzania - videos
    13. Exploring health in Tanzania - living with HIV
    14. Exploring health in Tanzania - reflection
    15. Use of appropriate technology
    16. Technology - sawdust stoves and clean water (videos)
    17. Technology - building good roads
    18. Use of appropriate technology - reflection
    19. Access to credit and micro credit
    20. Microcredit in the community (videos)
    21. Microcredit in the news
    22. Microcredit - reflection
    23. The origins of microcredit
    24. What are the pros and cons of microcredit?
    25. Empowerment of women
    26. Issues relating to empowerment of women (video)
    27. Empowerment - in the news
    28. Empowerment - reflection
    29. Income distribution
    30. Lorenz curve and Gini Coefficient
    31. Income distribution - Tanzania
    32. Income distribution - case studies
    33. Income distribution - reflection
    34. Building a development database (part 7)
  7. 4.3 The role of domestic factors in economic development (questions)
  8. 4.4 The role of international trade (notes)
  9. 4.4 The role of international trade (questions)
  10. 4.5 The role of Foreign Direct Investment (FDI) (notes)
  11. 4.5 The role of foreign direct investment (questions)
  12. 4.6 The role of foreign aid and multilaterial development assistance (notes)
  13. 4.6 The role of foreign aid and multilateral development assistance (questions)
  14. 4.7 The role of international debt (notes)
  15. 4.7 The role of international debt (questions)
  16. 4.8 The balance between markets and intervention (notes)
  17. 4.8 The balance between markets and intervention (questions)
  18. Print View

Lorenz curve and Gini Coefficient

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Gini coefficient

If there is a completely equal distribution of income, then G=0 (X=0 and X/Y must be 0)and the Lorenz curve is a diagonal line.

The distribution of income becomes more unequal as G increases and gets closer to 1, and this could occur, for example, if more people received nothing, as the lower end of the Lorenz curve would move rightwards along the horizontal axis.

As 100% of the population must receive 100% of total income, the top right hand end of the Lorenz curve must touch the top right hand end of the diagonal. However, if the top quintile groups obtain a higher proportion of income, the Lorenz curve will bulge further to the right in its upper regions before it reaches the top right hand corner.

In the hypothetical extreme where one person earned all the money and everyone else obtained nothing, the area below the Lorenz curve would disappear and G would be very near to 1. Thus G will lie between 0 and 1, and the greater it is, the more the inequality.

The higher the Gini coefficient, the more unequally income is distributed.


World Gini Coefficients 2009 (CIA World Factbook)

As economies grow and develop, income distribution is likely to widen. As economies grow, they tend to reward the economically strong rather than the weak. The rich get richer while the poor get poorer. In most developed economies, progressive tax systems and social security systems exist to help those at the bottom of the economic pile to varying degrees. However, many developing economies do not have the institutional framework required to achieve this redistribution and as a result, income distribution will often worsen during the process of economic growth.

An unequal distribution of wealth and income can act as a barrier to growth. Those on the lowest income levels often have the highest marginal propensity to consume and if they get an increase in their incomes, they are likely to spend most of this, if not all. This additional demand will help drive economic growth. However, if growth simply means that the rich get richer (and perhaps even move their money overseas) this will act as a constraint on development.