Accuracy and reliability

Overall accuracy

No quantitative measures of total uncertainty have been estimated. For the total purchase of materials the sample uncertainty is approximately 5 pct. For the total purchase of materials the sample uncertainty is approximately 5 pct. The statistic has a number of sources of measuring error. These are assessed as being greater than the sample uncertainty and sets a limit on the quality of the numbers. There are no quantitative measures of the measuring error. The over coverage has not been estimated. The reply rate for the statistical year 2012 was 83 pct. The item-non response rate for the total purchase of services was under 0,5 pct. The item-non response rate for the total purchase of materials was under 4,1 pct.

Sampling error

Sample uncertainties for the scaled numbers have been calculated. For the total purchase of materials the sample uncertainty is approximately 5 pct. For the total purchase of materials the sample uncertainty is approximately 3.5 pct. For individual industries the sample uncertainty for the purchase of materials is under 30 pct and for the purchase of services, under 12 pct.

Non-sampling error

The statistic has a number of systematic errors. These are estimated as being a greater source of uncertainty than the sample uncertainty. The companies do not report their purchases in great enough detail and this sets a limit on the precision. There are no quantitative measures of this. The over-coverage-rate has not been estimated. The response rate was 83 pct. for the survey year 2012 at the time of publication. The item non-response rate is 0.4 for the total purchase of services and 4.1 for the total purchase of materials. Item non-response rate , total purchase of materials: 4,1 pct.

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

It is estimated that the statistic has a reasonable quality at an aggregated level. At material-group level it is estimated that the quality is low. No quantitative measures of the total uncertainty of the statistic have been done. For the total purchase of materials the sample uncertainty is approximately 5 pct. For the total purchase of materials the sample uncertainty is approximately 3.5 pct. The statistic has a number of measuring errors. These are estimated as being a greater source of uncertainty than the sample uncertainty. The companies do not report their purchases in great enough detail and this sets a limit on the precision. There are no quantitative measures of this. The over-coverage-rate has not been estimated. The response rate was 83 pct. for the survey year 2012 at the time of publication. The item non-response rate is 0.4 for the total purchase of services and 4.1 for the total purchase of materials.

Item non-response rate , total purchase of materials: 4,1 pct.

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

The statistics include only final data.