Abstract
The variogram is the keystone of Kriging. Much research has been devoted to modelling the variogram from structural analysis of observations. However, there are many instances when the variogram is needed and there are no observations to base on. This can be due to budget constraints, physical or temporal obstacles, or a demand for a priori variogram in Bayesian geostatistics and spatial sampling design. Using expert knowledge that is elicited with a formal statistical expert elicitation procedure is suggested. In this study, we designed a protocol for a wellstructured elicitation procedure to elicit the variogram from expert knowledge. The protocol has two main stages: elicitation of the marginal probability distribution and elicitation of the variogram. We built a web-based tool to facilitate the procedure. A case study was carried out to quantify spatial accuracy of a legacy map of the volumetric soil water content at field capacity. Expert elicitation returns a variogram that has a Matérn model shape with nugget = 0.45, partial sill = 54.57, range = 25410 meters and kappa = 0.40. The results show that the online elicitation tool satisfactorily captured expert opinion although, currently, it is only a prototype that needs to be further developed.
Original language | English |
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Title of host publication | Proceedings of the 10th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences, 10-13 July 2012, Florianopolos, Brazil |
Editors | C. Vieira, V. Bogorny, A. Ribeiro Aquino |
Publisher | Federal University of Santa Catarina |
Pages | 251-256 |
Publication status | Published - 2012 |
Event | 10th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental SciencesFlorianopolos, SC, Brazil - Duration: 10 Jul 2012 → 13 Jul 2012 |
Conference
Conference | 10th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental SciencesFlorianopolos, SC, Brazil |
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Period | 10/07/12 → 13/07/12 |