Higher Partials of fStress

Jan de Leeuw

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arXiv · 2407.18314

Higher Partials of fStress

Jan de Leeuw

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Abstract

We define *fDistances*, which generalize Euclidean distances, squared distances, and log distances. The least squares loss function to fit fDistances to dissimilarity data is *fStress*. We give formulas and R/C code to compute partial derivatives of orders one to four of fStress, relying heavily on the use of Faà di Bruno's chain rule formula for higher derivatives.

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Jan de Leeuw. 2024-07-25. Higher Partials of fStress. https://arxiv.org/abs/2407.18314

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