2940.0.55.001 - Information Paper: Measuring Net Undercount in the 2011 Population Census, 2011  
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 06/07/2011   
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A web service that assigns a geographic classification to an address or a list of addresses and is used for linking and matching activities.

Automated Data Linking (ADL)

Automated linking processes used to determine possible links between Census and PES data, before any clerical matching process has begun. It employs a probabilistic linking method that uses a range of personal and address characteristics to evaluate the likelihood that a PES and Census record pertain to the same individual.

Census Collection Districts (CDs)

The basic geographic unit of collection in the 2006 Census. It is generally an area that one collector can deliver and collect forms over a specified collection period.

Collect, Analyse, Reduce, De-duplicate and Systematise (CARDS)

A series of processes which prioritises and organises ADL output for use by the MSS system.

Collector Workloads (CLWs)

The basic geographic unit of collection for the 2011 Census. It is generally an area that one collector can deliver and collect forms over a specified collection period.

Computer Assisted Interviewing (CAI)

A method of data collection whereby responses are recorded directly into an electronic questionnaire on a notebook computer.

Correlation bias

A bias arising when people who were not counted in the Census are more likely to be missed in the PES than people with similar values of the characteristics used in PES estimation (such as age, sex and Indigenous status) who were counted in the Census.


The survey coverage refers to the population units which have a chance of being selected in the survey sample. For the quality of the survey estimates, it is desirable that the survey coverage matches as closely as possible the survey scope. Coverage rules are generally applied in all household surveys to ensure that each person is associated with only one dwelling, and hence has only one chance of selection.

Discrete Indigenous community

A geographic location, bounded by physical or legal boundaries, and inhabited or intended to be inhabited predominantly by Indigenous people, with housing or infrastructure that is either owned or managed on a community basis.

Estimated Resident Population (ERP)

The official measure of the population of Australia based on the concept of residence. It refers to all people, regardless of nationality or citizenship, who usually live in Australia, with the exception of foreign diplomatic personnel and their families. It includes usual residents who are overseas for less than 12 months. It excludes overseas visitors who are in Australia for less than 12 months.

ERP rebasing

Following each Census of Population and Housing, ABS rebases its official estimates of population - the Estimated Resident Population (ERP) series. This provides the basis for population estimates until the next Census. The rebased Census-year ERP together with other Census information and data on intercensal components of population change allows ERP revisions to be made back to, but not including, the previous Census.

Freely Extensible Biomedical Record Linking (FEBRL)

Probabilistic linking software developed at the Australian National University used for PES automated data linking activities.


A statistical process for predicting values where no response was provided to a question and a response could not be derived.

Imputed dwelling (in Census)

A dwelling which is determined to be occupied in the Census and where Census data is imputed because no Census form was received.

Indigenous Community Frame (ICF)

The listing of all discrete Indigenous communities from which the sample of communities is selected.

Late return

A Census form which was returned after the start of PES enumeration.

Mainstream sample

All PES private dwelling sample selections other than those from discrete Indigenous communities.

Match and Search System (MSS)

The main PES clerical review facility, which allows processors to search, view, compare, and record matches between PES and Census data.

Non-private dwelling

An establishment which provides a communal type of accommodation, such as a hotel, motel, hospital or other institution.

Non-sampling error

Error arising from inaccuracies in collecting, recording and processing the data. Every effort is made to minimise non-sampling error by the careful design of questionnaires, intensive training and supervision of interviewers, and efficient data processing procedures. Non-sampling error also arises because information cannot be obtained from all persons selected in the survey and data are imputed based on assumption about the non-respondents.

Outstation (or homeland)

A discrete Indigenous community that has a population of fewer than 50 people AND is administered by, or linked to, an organisation such as a Resource Agency or larger parent discrete Indigenous community for the provision and maintenance of services.

Private dwelling

A residential structure which is self-contained, owned or rented by the occupants, and intended solely for residential use. A private dwelling may be a flat, part of a house, or even a room, but can also be a house attached to, or rooms above, shops or offices.

Sampling error

Error occuring because a sample, rather than the entire population, is surveyed. One measure of the likely difference resulting from not including all dwellings in the survey is given by the standard error. There are about two chances in three that a sample estimate will differ by less than one standard error from the figure that would have been obtained if all dwellings had been included in the survey, and about nineteen chances in twenty that the difference will be less than two standard errors.


Within household surveys in the ABS, survey scope is considered to be the population about which inferences are desired: that is, when the results are published, the population to which they refer.

Search address

An address where a person was reported to be staying on Census night or where a person may have been included on a Census form. PES processing attempts to locate a Census form for each search address, in order to determine the number of times (if any) a person enumerated in the PES was included on a Census form.

Unoccupied dwelling (in Census)

A structure built specifically for living purposes which is habitable but the Census Collector was certain was unoccupied on Census night.