# Gini coefficient

- A statistic conventionally used in order to describe in summary form the degree of inequality in distributions (usually of income and wealth). It is calculated by determining the area between a Lorenz curve of the distribution (that is a graph of the cumulative income share against the cumulative share of recipients) and the line of perfect equality. This area is then expressed as a percentage of the whole triangular area under the diagonal. The resulting statistic reduces the position of the curve to a single figure. A distribution of perfectly equal incomes has a Gini coefficient of zero. As inequality increases, and the actual Lorenz curve bellies out, the Gini coefficient moves towards its maximum value of 1 (only one recipient receives all income).The Gini coefficient is one of several measures of inequality (others include the coefficient of variation and inter-decile ratio) which purport to rest exclusively on the mathematical properties of a distribution. Such indices tend to give conflicting answers when they are asked to determine whether any particular distribution is more unequal than another. For example, one statistic may be more sensitive than another to a scatter of low incomes, and each indicator tends to attach different weights to different forms of inequality within the distribution. More sophisticated measures-such as the Theil index and Atkinson index-have therefore been devised, which attempt to express in a single number the degree of inequality in a distribution as a whole, but in ways which explicitly weight inequalities in different parts of the distribution-in line (for example) with the observer's judgements about the relative value of each additional unit of currency accruing to a rich as against a poor person. (Atkinson's formula for his index contains a coefficient which expresses the researcher's aversion to inequality.)A good account of the various properties of the different measures will be found in,
*Egalitarianism and the Generation of Inequality*(1988). See also income distribution.

*Dictionary of sociology.
2013.*

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**Gini coefficient**— The Gini coefficient is a measure of statistical dispersion most prominently used as a measure of inequality of income distribution or inequality of wealth distribution. It is defined as a ratio with values between 0 and 1: A low Gini coefficient … Wikipedia**Gini coefficient**— coefficient developed by Corrado Gini which is a number between zero and one that is a measure of inequality … English contemporary dictionary**Gini coefficient**— G= ½ Σ(Xi Yi) Xi and Yi are two sets of data expressed as a percentage. The coefficient shows how alike they are from identical (0) to as unidentical as they could be (100) … Geography glossary**Coefficient De Gini**— Pour les articles homonymes, voir Gini (homonymie). Courbe de Lorenz et coefficient de Gini Le coefficient de Gini est une mesure du degré d inégalité … Wikipédia en Français**Gini**— can have several meanings:*G.I.N.I., a predecessor organization to Post Polio Health International *Corrado Gini, an Italian statistician, demographer, sociologist and developer of the Gini coefficient, which measures income inequality in a… … Wikipedia**coefficient**— UK US /ˌkəʊɪˈfɪʃənt/ noun [C] ► in mathematics, a value that appears in front of and multiplies another value: »In 2x + 4y = 7, 2 is the coefficient of x. ► a number or a method of calculating a number that measures the characteristics of a… … Financial and business terms**Coefficient de Gini**— Pour les articles homonymes, voir Gini (homonymie). Le coefficient de Gini est une mesure du degré d inégalité de la distribution des revenus dans une société donnée, développée par le statisticien italien Corrado Gini. Le coefficient de Gini est … Wikipédia en Français**Gini Index**— A measurement of the income distribution of a country s residents. This number, which ranges between 0 and 1 and is based on residents net income, helps define the gap between the rich and the poor, with 0 representing perfect equality and 1… … Investment dictionary**Gini, Corrado**— ▪ Italian statistician born May 23, 1884, Motta di Livenza, Treviso, Italy died Mar. 13, 1965, Rome Italian statistician and demographer. Gini was educated at Bologna, where he studied law, mathematics, economics, and biology. He was… … Universalium**Gini**— (homonymie) Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. Gini peut être : une boisson : Gini une mesure d inégalité des revenus : Coefficient de Gini un statisticien et sociologue… … Wikipédia en Français