Lorenz curve
Topic: Graphical Representation of Data and Thematic Maps · NCERT: Beyond NCERT
Meaning
A Lorenz curve shows how evenly something is shared. The cumulative share of people or areas goes on one axis. The cumulative share of a quantity, such as income, land or industrial output, goes on the other. ("Cumulative" means added up step by step.) If everything were shared equally, the points would fall on the diagonal, called the line of equality. The more the curve bows away from that line, the greater the inequality. The Gini coefficient turns this into one number: 0 means perfect equality and 1 means everything is held by one.
Example
In India, small and marginal farmers are the majority of landholders but own a much smaller share of farmland. A Lorenz curve of landholdings therefore sags well below the line of equality.
Don't confuse with
- Gini coefficient: this is a single number taken from the Lorenz curve. It is the gap between the curve and the diagonal, divided by the whole area under the diagonal. The curve itself is the graph.