摘要：AbstractBackgroundNonlinear relationships are common in the environmental discipline. Spreadsheet packages such as Microsoft Excel come with an add-on for nonlinear regression, but parameter uncertainty estimates are not yet available. The purpose of this paper is to use Monte Carlo and bootstrap methods to estimate nonlinear parameter uncertainties with a Microsoft Excel spreadsheet. As an example, uncertainties of two parameters (αandn) for a soil water retention curve are estimated.ResultsThe fitted parameters generally do not follow a normal distribution. Except for the upper limit ofαusing the bootstrap method, the lower and upper limits ofαandnobtained by these two methods are slightly greater than those obtained using the SigmaPlot software which linearlizes the nonlinear model.ConclusionsSince the linearization method is based on the assumption of normal distribution of parameter values, the Monte Carlo and bootstrap methods may be preferred to the linearization method.
关键词：KeywordsEnBootstrapMonte CarloSoil water retentionParameter uncertaintyExcel
