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Number of Motor Vehicles
On this page:
Applicable to: Occupied private dwellings
1. 1 motor vehicle
2. 2 motor vehicles
3. 3 motor vehicles
4. 4 or more motor vehicles
& Not stated
@ Not applicable
Total number of categories: 7
More Detailed Description
Quality Statement - Number of Motor Vehicles (VEHD)
There are many aspects which can affect the quality of Census data; the following information should be considered when viewing data on Number of Motor Vehicles (VEHD).
This data is automatically captured from hand written numeric responses (or "None" check box responses). This process is subject to very low levels of recognition error. After the data is captured, any outlying values are manually checked to ensure that they match the actual response on the form. All numeric responses are accepted as reported; the data may then include a small proportion of dwellings with unusually large number of vehicles. The data is also subject to normal sample checks to ensure an acceptable level of quality.
The non-response rate for 2006 was 7.8% compared with 6.5% for 2001. Part of this non-response is attributable to the 4.2% of private dwellings which were occupied on Census Night but did not return a completed form. In these cases as the question for Number of Motor Vehicles (VEHD) has not been answered then the values remain not stated. In 2001, 2.0% of private dwellings did not return a completed form.
For the 2006 Census the "None" check box was added, whereas in 2001 respondents were requested to write in "0" in the written response field.
The ABS aims to produce high quality data from the Census. To achieve this, extensive effort is put into Census form design, collection procedures, and processing procedures.
There are four principal sources of error in Census data: respondent error, processing error, partial response and undercount. Quality management of the Census program aims to reduce error as much as possible, and to provide a measure of the remaining error to data users, to allow them to use the data in an informed way.
When completing their Census form, some people do not answer all the questions which apply to them. In these instances, a 'not stated' code is allocated during processing, with the exception of non-response to age, sex, marital status and place of usual residence. These variables are needed for population estimates, so they are imputed using other information on the Census form, as well as information from the previous Census.
The processing of information from Census forms is now mostly automated, using scanning, Intelligent Character Recognition and other automatic processes. Quality assurance procedures are used during Census processing to ensure processing errors are kept at an acceptable level. Sample checking is undertaken during coding operations, and corrections are made where necessary.
The Census form may be completed by one household member on behalf of others. Incorrect answers can be introduced to the Census form if the respondent does not understand the question or does not know the correct information about other household members. Many of these errors remain in the final data.
More detailed information on data quality is available in the 2006 Census Dictionary (cat. no. 2901.0), in the section titled Managing Census Quality.