The statistics is based on a survey sample of approx. 3.000 units weighted to a frame of approx 18.000 enterprises. The statistics is compiled in one joined questionnaire which covers both the R&D domain and the innovation statistics. An extensive validation process of the data is carried out. One part of the validations is integrated in the data collection in the dynamic web-questionnaire, another part is carried out after the data collection using micro- and macro validation techniques.
The statistics are compiled on the basis of questionnaires. Questionnaires are web-based (since 2011) and close to 100 per cent of the responses comes from this media. The sample is of 3.000 enterprises from most size classes and all NACE-industries in the Danish enterprise sector. The sample is based on a frame of 9.000 units. Annex for the population
It is mandatory to reply to the statistics using the web-based questionnaire from Virk
An extensive validation process of the data is carried out. One part of the validations is integrated in the data collection in the dynamic web-questionnaire, another part is carried out after the data collection using micro- and macro validation techniques. The individual reports from the enterprises are compared to former years reports and the registered information on number of employees and turnover. Outlier detection is also used as a validation process.
A stratified random sampling is used on the basis of the activity of the enterprise and the number of employees. By grossing up a weighting and calibration using regression techniques is applied to the weight of the individual enterprise.
Non-response from enterprises of a certain size are imputed with "last known data" (cold deck imputation). If data from former surveys is not available for the specific record then nearest neighbor (hot deck, donor imputation) is used. Other enterprises that have not answered the questionnaire (unit non-response) are handled during the enumeration.
Not relevant for these statistics.