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arXiv · 2410.01223

Statistical Taylor Expansion: A New and Path-Independent Method for Uncertainty Analysis

Abstract

Statistical Taylor expansion is a rigorous extension of conventional Taylor expansion that replaces each precise input variable with a random variable of known distribution and sample count, then computes the mean, deviation, and a bounding reliability of every result. By tracking the propagation of input uncertainties through all intermediate steps, it renders the final result path-independent, with precise quantification of the tracking quality. This path-independence sets it fundamentally apart from conventional numerical approaches, which are path-dependent. This study presents an implementation called variance arithmetic and demonstrates its performance across diverse mathematical applications. This study also reveals the potentially substantial impact of numerical errors in library functions, the defect of applying input uncertainties as weights in conventional regression, and the modeling error of the discrete Fourier transformation. The concept of statistical algebra is also introduced.

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Chengpu Wang. 2024-10-02. Statistical Taylor Expansion: A New and Path-Independent Method for Uncertainty Analysis. https://arxiv.org/abs/2410.01223

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