Accuracy and reliability

Overall accuracy

No quantitative measures of uncertainty have been calculated besides the sample uncertainty, which is 1.5 pct. for the total turnover. For the construction industry totals the sample uncertainty is under 11 pct., while the totals for the types of construction work are under 9 pct. For the cross between industry and type of work, the sample uncertainty can be as high as 90 pct., but generally lies in the range 5-15 pct. The uncertainty of the quarterly changes, however, is far smaller, since the professional units in the sample are not replaced each quarter. The over coverage is estimated to be under 1 pct., un-weighted. The number has been estimated from the number of respondents that point attention to the fact that they have been placed in the wrong industry. The uncertainty that results from non-response, wrong reported numbers and misunderstandings has been sought minimized by control and re-contact with the companies. The variable that the companies are asked about is well defined, so misunderstandings are estimated to be few. The response rate is high.

Sampling error

Sample uncertainties for the scaled turnover have been calculated. For the total turnover the sample uncertainty is approximately 1.5 pct. For the construction industry totals the sample uncertainty is under 11 pct, while the totals for the types of construction work are under 9 pct. For the cross between industry and type of work, the sample uncertainty can be as high as 90 pct, but generally lies in the range 5-15 pct. The uncertainty of quarterly changes are lower than the sample uncertainty as the sample is only changed partly every 4 quarters.

Non-sampling error

The statistic has a number of sources of systematic errors. The systematic errors are estimated to be small. The over coverage is estimated to be under 1 pct., un-weighted. The number has been estimated from the number of respondents that point attention to the fact that they have been placed in the wrong industry. The uncertainty that results from non-response, wrong reported numbers and misunderstandings has been sought minimized by control and re-contact with the companies. The variable that the companies are asked about is well defined, so misunderstandings are estimated to be few. The response rate is high.

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

For the total employment the sample uncertainty is approximately 1.5 pct. For the construction industry totals the sample uncertainty is under 11 pct, while the totals for the types of construction work are under 9 pct. For some crosses between industry and type of work (which totals less than 50 million DKK), the sample uncertainty can be as high as 50 pct, but generally lies in the range 5-15 pct. The over coverage is estimated to be under 1 pct., un-weighted. The number has been estimated from the number of respondents that point attention to the fact that they have been placed in the wrong industry.

The uncertainty that results from non-response, wrong reported numbers and misunderstandings has been sought minimized by control and re-contact with the companies. The variable that the companies are asked about is well defined, so misunderstandings are estimated to be few. The response rate is high. By publication, around 90 pct. of the professional units have answered.

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

Only final numbers are published. In case of changes in the statistical methods, revisions of earlier numbers are performed.