Nordic Statistical Meeting 26.-28.8.2019, Helsinki

1. Re-thinking Data Validation
Anette Morgils Hertz – ahz@dst.dk
Katja Overgaard – kao@dst.dk
Statistics Denmark
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2. Motivation
• Look at data across statistical
domains
• Special knowledge on
international production of
large multinationals
necessary
• Complex and time consuming
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3. Motivation
• Given the same resources available – how to establish this new
validation routine?
• Rearranging our validation routines
• Always focus on the errors that matter the most (Key account system)
• Monitoring the performance of the validation routines, to ensure they
perform optimally (monitoring report)
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4. Agenda
• About us
• SKV and Validation team
• Validation Routines then and now
• Monitoring the Validation Routines
• Key Account System
• Conclusion
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5. About us
• What is International Trade in Goods (ITGS)?
• Import/Export of goods
• Around 9000 commodity codes and 250 country codes
• Published monthly
• What is International Trade in Services (ITSS)?
• Import/Export of services
• Around 70 service codes and 250 country codes
• Published aggregated monthly and detailed quarterly
• What is Balance of Payments
• Use data from different sources incl. ITGS and ITSS
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6. SKV and Validation Team
• SKV team
• SKV → Company critical to our statistics
• Team dedicated to validate the reported data from these companies
• Validation team
• Responsible for all other validation and communication with the
companies
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Team No. companies
validated
Value validated
SKV 21 42,3 Bill.
Validation 82 4,01 Bill.

7. Validation Routines then and now
• Old system: 59 different valdation routines
• Now: Some validation routines are closed, others rearranged
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8. Key Account System
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One person = One company

9. Key Account System
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Changing weights →

10. Monitoring Validation Routines
• Monitoring report
• Measuring the quality of a validation routine:
ℎ𝑖𝑡 𝑟𝑎𝑡𝑒 =
𝑎𝑐𝑡𝑢𝑎𝑙 𝑒𝑟𝑟𝑜𝑟𝑠
𝑖𝑑𝑒𝑛𝑡𝑖𝑓𝑖𝑒𝑑 𝑝𝑟𝑜𝑏𝑎𝑏𝑙𝑒 𝑒𝑟𝑟𝑜𝑟𝑠
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11. Monitoring Validation Routines
• Graphs for comparison
• Absolute errors
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Period Value in DKK Amount
2019M05 3.272.563 1

12. Conclusion
• To spend our resources optimally we must monitor every
validation routine
• A change of focus is necessary
• Start with the potential errors with the biggest impact
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13. Thank you!
Anette Morgils Hertz, email: ahz@dst.dk
Katja Overgaard, email: kao@dst.dk
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