At the Adam Smith Institute blog, Tim Worstall explains why measuring relative poverty isn’t helpful:
Here actually is the problem with using relative poverty as a measure:
Compared to the 1960s, China today has higher income inequality, but also incomparably lower levels of material poverty. By Brady’s definition, China was less impoverished in the near-starvation years of the 1960s than it is as an economic superpower today. According to the OECD, during the last three decades the share of Chinese living in absolute poverty dramatically declined from eight in ten to one in ten (Garroway and de Laiglesia 2011). During the same period, relative poverty, measured exactly as Brady measures it, roughly doubled. Although inequality and relative poverty are not irrelevant for measuring the well-being of a society, we should be apprehensive about a measure of poverty that is incapable of detecting the largest decline in material poverty in human history.
As pointed out, a measure of poverty that not just ignores, but actually gets the sign wrong on, the largest reduction in poverty in the history of our species is of limited value.
[. . .]
Which leads us to something of a conclusion: it’s fine to consider the distribution of incomes within a society. But we do it rather too much with the constant political obsession over relative poverty. We need to be paying a lot more attention to absolute standards of living: most especially how these change over time. Most specifically I’m thinking about the effects attempts to reduce relative poverty might affect our ability to increase absolute standards of living in the future.
