The study that shows life is a lot more unequal than you (probably) think

Voters, take note: a World Bank survey of Indonesian households suggests people have a strong tendency to underestimate the extent of inequality - and it reveals how this can affect their political allegiance, too

Which matters more: actual levels of inequality, or the levels that people perceive to exist? There is now clear evidence that perceptions of inequality have a profound impact on societies all over the world - and that people aren't very good at judging the reality for themselves.

The trouble is, almost all research on inequality focuses on actual levels, which means our understanding of how people respond to inequality has been based on the assumption that people's perceptions align with reality. And this, according to a unique survey of Indonesian people by the World Bank, is just not true.

Perceptions of inequality have a profound impact, because people aren't very good at judging the reality for themselves

Related: Voices of the 1%: how do Britain's highest earners feel about their income?

Related: Inequality index: where are the world's most unequal countries?

The results of this survey suggest Thomas Piketty's famous theory should be modified to capture perceptions of mobility

Related: The Inequality Project: the Guardian's in-depth look at our unequal world