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Model Uncertainty

Stochastic Modeling and Environmental Change

  1. Chris Chatfield

Published Online: 15 SEP 2006

DOI: 10.1002/9780470057339.vam030

Encyclopedia of Environmetrics

Encyclopedia of Environmetrics

How to Cite

Chatfield, C. 2006. Model Uncertainty. Encyclopedia of Environmetrics. 4.

Author Information

  1. University of Bath, UK

Publication History

  1. Published Online: 15 SEP 2006


The modeling of complex environmental stochastic systems is a difficult task. There may be little or no background theory, the data may be of doubtful quality, and it is not always clear what the objectives are. Nevertheless, scientists have made substantial progress in getting a better insight into environmental relationships and changes. However, much remains to be done, especially in regard to the thorny topic of model uncertainty. Although it is widely recognized that all models are approximations and need to be modified and improved as more information becomes available, many scientists continue to make predictions from models as if they really believe them to be true. As a result, the accuracy of out-of-sample predictions is typically (much) worse than would be expected from the within-sample fit.