Paper by me to the November
RSS/ONS conference on quality issues ‘Are the census outputs fit for purpose?’
(a rhetorical question if ever there was one). It
compares undercount in 1991 and 2001 showing the increase in the
worst-affected areas (but supports the One Number Census’s inclusion of
estimates of that undercount in census output), describes how to measure the
impact on census analysis of eliminating all 1s and 2s from census output, and
critiques ONS’s construction of a population
estimate from the census results and other information, looking forward to
2011. 17 pages.
There are a number of important matters
covered in Ludi's judicious paper. But what
caught my attention is the way 1s and 2s have been eliminated (to protect
privacy/confidentiality etc) that must surely conflict with several Code of
Practice principles? Ludi says that the Census output does not
identify the 0s and 3s that are genuine for those that are the results of
elimation of 1s an 2s.
Can it really be that the ONS ( for reasons of
confidentiality) is saying that ANY census statistic of 3 or less could be
0, 1, 2, or 3?
And can it really be that the ONS is relying on
Ludi to give guidance to users on how to aggregate such statistics to
produce statistics that presumably should include a figure for the
estimated confidentiality-protection error?
Ray Thomas
35 Passmore, Tinkers Bridge, Milton
Keynes MK6 3DY
Email: [log in to unmask]
Tel 01908
679081 Fax 01908 550401