Accuracy and reliability
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Section for Earnings and Absence, Social StatisticsHege Susanne Hauglund
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Since the index is based on information on wages obtained from more or less all publicly employed persons through public pay transfer systems, the accuracy and reliability of the index is considered to be high. At the same time, there are some small uncertainties regarding the index which it is a good idea to be aware of when applying the index.
Overall accuracy
The index is based on data for almost all employees in the state, regional- or municipal authorities. Data are mainly collected through public pay transfer systems, but a part of the data are received through smaller pay transfer systems of private enterprises. The overall accuracy is considered to be rather high as the data are collected through reliable and well-functioning systems for transmission, and because the data cover a large portion of the statistical population.
Sampling error
The indices are based on data extracts covering all government employees. Consequently, the indices are not subjected to sampling errors.
Non-sampling error
There is a possibility of uncertainty in the understanding and reporting of the concepts wages and hours worked in the received data. Furthermore, these has been some challenges concerning data received from the municipal authorities, as many of these have changed the payroll system for transfer. Problems like these are continuously discussed with the people or institutions involved to ensure that the data contain the highest possible quality.
In addition to the above uncertainties, there are also some challenges in connecting data of state employees with the Business Registers to collect the right information on which sectors of economic activity and what part of the public sector the person is employed in. This is partly caused by poor quality in the reporting of the production number of the local unit where the person is employed, and due to misplacements of regional or municipal employees in economic sectors based on their placement in a city- or regional hall, although their work function is not administrative. Statistics Denmark continuously work to improve these errors and uncertainties by using available administrative information obtained from the collected data, like e.g. information on users id and occupation code.
There exists no number of the uncertainty.
Quality management
Statistics Denmark follows the recommendations on organisation and management of quality given in the Code of Practice for European Statistics (CoP) and the implementation guidelines given in the Quality Assurance Framework of the European Statistical System (QAF). A Working Group on Quality and a central quality assurance function have been established to continuously carry through control of products and processes.
Quality assurance
Statistics Denmark follows the principles in the Code of Practice for European Statistics (CoP) and uses the Quality Assurance Framework of the European Statistical System (QAF) for the implementation of the principles. This involves continuous decentralized and central control of products and processes based on documentation following international standards. The central quality assurance function reports to the Working Group on Quality. Reports include suggestions for improvement that are assessed, decided and subsequently implemented.
Quality assessment
All in all, the index is considered to be of a high quality. Data are mainly collected through the public pay transfer systems and normally contain few errors or missing values. Data have been improved over time as Statistics Denmark on a continuous basis has tried to correct for errors by taking advantage of the information available through the administrative systems. In addition, Statistics Denmark has also made sure to contact the respective enterprises submitting data with errors, to make sure the enterprise make corrections for future transmissions. Still, there are some uncertainties present that can have an impact on the quality of the data. For example, there has been a problem in linking the right branch of economic activity and placement in the public sector to an observation. This ultimately can have an impact on the quality if not corrected for. Read more about uncertainties under the section of Non-sampling error and A4.
With respect to the index on state employees for the 1st and 2nd quarter of 2015, it should be mentioned that the index due to data quality issues, does not include data on employees from the Church of Denmark. Work is in progress to resolve the issue so that data on these employees are once again included in the index for the 3rd quarter of 2015.
Data revision - policy
Statistics Denmark revises published figures in accordance with the Revision Policy for Statistics Denmark. The common procedures and principles of the Revision Policy are for some statistics supplemented by a specific revision practice.
Data revision practice
There exists no practice of revision of earlier results.