Income Inequality — Revision Notes

⚡ 30-Second Revision

Income flow ≠ consumption ≠ wealth stock.
Mean can rise while median stays fixed.
Gini 0.30 = index 30 on another scale.
Proportional doubling preserves relative shares.
Poverty line, Gini and top share answer different questions.

2-Minute Revision

Read inequality through definitions and distribution. Use mean, median, shares and Gini for their respective purposes. Relative inequality can stay unchanged while absolute gaps grow and poverty falls. Dated Indian estimates must retain their variable, method and source rather than being compared because their numbers look similar.

5-Minute Revision

Calculate the mean and median of 10, 20, 30 and 40, then replace 40 with 140. Separately double the original four incomes and apply a fixed poverty line of 15. Explain what changes in averages, relative shares, absolute gaps and poverty.

Vyyuha Quick Recall

Variable, unit, period, measure, method.