USING THE CURF
ABOUT THE CURF
The data included in the May 2014 Employee Earnings and Hours (EEH) Expanded CURF is released under the provisions of the Census and Statistics Act 1905. This legislation allows the Australian Statistician to release unit record data, or microdata, provided this is done “in a manner that is not likely to enable the identification of a particular person or organisation to which it relates”.
The ABS ensures the confidentiality of the data by:
- removing any information such as the name of the business that might uniquely identify a business or individual;
- changing a small number of values - particularly unusual values;
- controlling the detail available for all records on the CURF;
- excluding some data items that were collected;
- reducing the level of detail for some data items;
- controlling the modes of access to restrict access to more detailed data; and
- placing restrictions on how the data are used, supported by information in the User Manual: Responsible Use of ABS CURFs, the undertaking signed by the head of each organisation and the terms and conditions signed by each user.
Steps to confidentialise the data sets made available on the CURF are taken in such a way as to ensure the integrity of the data sets and optimise their content, while maintaining the confidentiality of respondents. Intending purchasers should ensure that the data they require, at the level of detail they require, are available on the CURF they are intending to use. The full list of survey data items included on the CURF is provided in the Excel spreadsheet entitled 'EEH CURF Data Items List
' accompanying this release.
Each employee record has a unique person identifier - ABSPID.
The May 2014 EEH Expanded CURF can be accessed via the RADL and ABSDL and is available in SAS, SPSS and STATA formats. The Expanded CURF comprises the following files:
- SAS FILE: EEH14E.SAS7BDAT contains the CURF data is SAS format
- SPSS FILE: EEH14E.SAV contains the CURF data is SPSS format
- STATA FILE: EEH14E.DTA contains the CURF data is STATA format
USE OF WEIGHTS
- DATA ITEMS LIST: contains all the data items, including details of categories and code values, that are available on the CURF.
The survey was conducted on a sample of employees from a sample of employers in Australia, and as such users need to take this into account when deriving estimates from the CURF. Each employee record contains a weight (FINPRSWT) and this weight indicates how many employees in the survey scope population are represented by this employee. Where estimates are derived from the CURF, it is essential they are calculated using the weights.
An employee's chance of selection in the survey varied considerably, depending on their employer's state, sector, industry and size. If an employee's survey weight is ignored, then no account will be taken of the employee's chance of selection, and the resulting estimates may be biased.
A number of the weights in the CURF have been slightly modified from the original survey weights for confidentiality reasons. This reweighting process has not resulted in significant changes to the estimates and the statistical validity of the CURF is not affected.
Weekly earnings data items have been perturbed and are expressed as continuous data items (in whole dollars only) on the CURF. Perturbation is a process of slightly altering the reported values to prevent identification of respondents. The distribution of values is not changed significantly through perturbation and the statistical validity of aggregate data is not affected.
HOURS PAID FOR
Hours paid for data were requested for all employees. However, hours paid for could not be provided for Managerial employees where there was no relationship between earnings and hours. As a result, data for hours paid for have only been produced for Managerial employees with a link between earnings and hours.
RECONCILIATION OF CURF WITH PREVIOUSLY PUBLISHED DATA
Steps to confidentialise the data made available on the CURF are taken in such a way as to maximise the content of the file while maintaining the confidentiality of respondents. The steps taken to preserve confidentiality include:
- omitting the States and Territories data item included in previously published output;
- reducing the level of detail available for the Employer unit size data item (available on the CURF in two broad groups);
- including industry data at the Division (1 digit) level only;
- perturbating all earnings data items; and
- modifying the weights for some records.
As a result, it may not be possible to exactly reconcile all statistics produced from the CURF with previously published statistics. However, these differences are not significant and should not diminish the value of the CURF in analysis.