Q.Which uniform method is used to measure absolute poverty for the different nations?

Relative poverty = poverty judged by comparing incomes of different groups; it reflects income inequality rather than a fixed minimum.

Relative poverty does not use a fixed poverty line. Instead, it compares the income or standard of living of one group of people with that of another. When the population is arranged from richest to poorest and the share of income of the lower sections is compared with that of the higher sections, the gap shows relative poverty.

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Absolute poverty across nations is compared using the World Bank's 'one dollar per day' (dollar-a-day) income method.

Absolute poverty means the inability to obtain the minimum basic necessities of life. To measure and compare it uniformly across different countries, a common international income standard is needed, because each country's own poverty line is in its own currency. The World Bank therefore uses the 'one dollar a day' benchmark (a person earning below this internationally comparable amount, in purchasing-power terms, …