Geospatial data assessment in Statistics Norway
Principle 1, national standards, NGIA, NSDI, quality, collaboration
All national geospatial data documentation in Norway must follow national standards given by Norway Digital – the national spatial data infrastructure (NSDI). All geospatial data produced by Statistics Norway and shared at geonorge.no (data hub for the NSDI) is documented accordingly. However, internal ready processed geospatial data which forms the basis for statistics shall according to archives legislation be long term stored and documented. For all non-geospatial data forming the basis for statistics, there is a central system in Statistics Norway for long term storage and documentation. Regarding point-based geospatial data, this can be handled just as all other non-geospatial data (but not area-based data, which will be subject to further assessments).
Before geospatial data arrives in Statistics Norway from the National Geospatial Information Agency (NGIA), it has already been subject to quality checks by the NGIA and the data has been assembled to national data repositories drawing from municipal databases. However, Statistics Norway is building routines for automatic checking and uploading to the internal central geodatabase. One key aspect in these routines is automatic procedures for comparing against last year’s data. If there are big differences, they are recorded to an output list for further inspection and quality assessments.
Regular meetings between the NGIA and Statistics Norway are conducted on issues related to the Cadastre and other geospatial data provided by the NMCA. These meetings concern all aspects of quality, not only the geospatial quality. Issues are discussed and the NGIA communicates the issues to the municipalities, which are the prime responsible organisations for maintaining the source data. A generic observation and experience from the cooperation in Norway; it is better to establish routines and checks when data is being put into the register, rather than trying to fix errors afterwards.