This Economic and Social Research Council (ESRC)-funded project aimed to develop automated procedures for maintaining the 2001 census output geographies in order to create 2011 output geographies for England and Wales. The Office for National Statistics (ONS) subsequently funded follow-up research concerned with evaluating the impacts of various related policy decisions and implementing the methods for the 2011 Census.
The geographical areas which were used to publish aggregate data from the 2001 census in England and Wales were designed to be optimal for the spatial distribution and socio-economic characteristics of the population at that time. In a minority of areas, these distributions and characteristics will have changed significantly by the time of the 2011 census, making the existing geographies unfit for the release of 2011 data.
The Census2011Geog project
was funded as part of the ESRC census programme and ran from 1 June 2008 to 31 January 2010. It aims were:
The Census2011Geog project conceptualised the problem and carried out detailed investigations of confidential 2001 and contemporary population data in order to ascertain the number and types of areas likely to be unfit for purpose in 2011. It further developed existing software to create a tool (AZTool) which automatically splits, merges or redesigns areas which are found to be over- or under-threshold (ie containing too many or too few people and/or households) at the time of the 2011 census. The project proposes an iterative process of maintenance, starting with output areas and then moving on to the higher levels of output geography, sequentially relaxing specified design criteria as required. It recommends the use of postcodes as the building blocks for the maintenance process.
The evidence base provided by the project informed policy decisions taken by the Office for National Statistics (ONS) for the 2011 Census and its software and methods were subsequently implemented by ONS to create the 2011 output areas for England and Wales, which were released in October 2012. We then proceeded to build on this work with the classification of workplace zones (COWZ) , initially for England and Wales (COWZ-EW) and then for the whole of the UK (COWZ-UK). The latter dataset has been formally published by ONS .