Changes to DWP households’ and pensioners’ incomes statistics 2015/16: statistical notice

Statistical notice about changes in the DWP Households Below Average Income and Pensioners’ Incomes Series statistics publications.


DWP Households Below Average Income and Pensioners’ Incomes Series statistical notice: measuring uncertainty

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This Department for Work and Pensions (DWP) statistical notice advises users of a change in methodology for measuring uncertainty in future:

  • Households Below Average Income (HBAI) statistics
  • Pensioners’ Income Series (PI) statistics

This change will take effect for the 2015/16 publication, pre-announced for publication at 16 March 2017.

The new methodology provides an improved measure of uncertainty around key HBAI and related PI estimates by:

  • creating resamples of the HBAI dataset by simulating stratified, cluster sampling for Great Britain (GB) and stratified sampling for Northern Ireland (NI)
  • creating a unique set of grossing factors for each resample using the HBAI grossing process to gross the GB and NI resamples to the United Kingdom (UK) population

The old methodology used a simpler technique of creating simple random resamples of the UK HBAI dataset and re-using the original HBAI grossing factors.

Published 16 February 2017