Computational methods for model reliability assessment

This paper investigates various statistical approaches for the validation of computational models when both model prediction and experimental observation have uncertainties, and proposes two new methods for this purpose. The first method utilizes hypothesis testing to accept or reject a model at a desired significance level. Interval-based hypothesis testing is found to be more practically useful for model validation than the commonly used point null hypothesis testing. Both classical and Bayesian approaches are investigated. The second and more direct method formulates model validation as a limit state-based reliability estimation problem. Both simulation-based and analytical methods are presented to compute the model reliability for single or multiple comparisons of the model output and observed data. The proposed methods are illustrated and compared using numerical examples.