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Data Quality Control Procedures within the Common European Phenological Data Platform COST 725. Ana Žust, Andreja Sušnik Environmental Agency of the Republic of Slovenia. 6 th COST 725 MC MEETING. Volos, Greece, September 21, 2006. September 21, 2006. The subject of the presentation:
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Data Quality Control Procedures within the Common European Phenological Data Platform COST 725 Ana Žust, Andreja SušnikEnvironmental Agency of the Republic of Slovenia 6th COST 725 MC MEETING Volos, Greece, September 21, 2006
September 21, 2006 The subject of the presentation: Results of the QUESTIONNAIREon national QCprocedures (the decision accepted on 5 th MC meeting in Dublin) The primary goal of the questionaire: To assemble information on national QC procedures and to provide the documentation on data quality assurance of the Common European Phenological Database 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 The countries which responded to the questionaire: 1.Austria 10. France 2.Germany 11. Ireland 3.Slovakia 12. Finland 4. Slovenia 13. Poland 5. Romunia (two institutions) 14. Norway 6. Litva 15. Spain 7. Latvia 8. Luxembourg 9. UK 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 1. Who is the owner of the data? • NHMS, IPG, Research Institutions, Educational and Research Institutions, Private Companies 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 3. Do the countries perform QC?A common protocol?For the needs of the common EPDB? 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 4. Use of the software programmes to alleviate the procedures of QC? 5. How to keep of data entering errors? Data entry is inherently prone to errors both simple and complex. Software programmes with incorporated constraints, syntax check constraints Simultaneous visual control Training the observers 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Steps of QC procedures 6. Visual control - elimination of first sight errors • Correct date format • Correct phenological phase entry • Completeness of the data. • . 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Steps of QC procedures 7. Logical control - eimination of rough errors 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Steps of QC procedures 8. Statistical data control- tracing of extreme values – outliers 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Steps of QC procedures 9. How do countries treat the outliers? 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Steps of QC procedures 10. Spatial control - comparison and correlation of data in space 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 Summary • Different approaches in national QC procedures(different phenology monitoring programmes, different spatial coverage (stations, plants and phases) different data periods), • Most frequent used visual and logical control, • Less used statistical and spatial control, • The methods are frequently combined with each other, • Individual data treatment, needs of a very experienced phenologist • The importance of exact observation rules and training of phenological observers • A few countries are in the procedure of developing seperate steps of QC procedures 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 11. What is the national estimate of the quality level of the data provided for EPDB? Data ownership and custodianship confers responsibilities for itsmanagement, quality control and maintenance of the data 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 CONCLUSIONS AND RECOMMENDATIONS • National phenological databases distributed in the common EDPB should be quality checked in advance by the country – owner of the data, • Further QC on the level of the common EPDB due to unhomogeneous coverage of different phenological objects is questionable – risk of erasing true extremes, • (visualisation of the spatial coverage of phenological objects by points on maps in friendly user manner – ZAMG example) • In the case that national QC is impossible the data should get a flag, 6th COST 725 MC meeting, Volos, Greece
September 21, 2006 CONCLUSIONS AND RECOMMENDATIONS • The usage of the data should start, • To accept the resort to detect the suspicious data or extremes through analyses, • The usage of the data in different analyses will additionaly enable platform to get a higher quality status. 6th COST 725 MC meeting, Volos, Greece