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arXiv · 2411.11461

Does wind affect the orientation of vegetation stripes? A copula-based mixture model for axial and circular data

Marco Mingione·Francesco Lagona·Priyanka Nagar·Francois von Holtzhausen·Andriette Bekker·Janine Schoombie·Peter C. le Roux
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Abstract

Motivated by a case study of vegetation patterns, we introduce a mixture model with concomitant variables to examine the association between the orientation of vegetation stripes and wind direction. The proposal relies on a novel copula-based bivariate distribution for mixed axial and circular observations and provides a parsimonious and computationally tractable approach to examine the dependence of two environmental variables observed in a complex manifold. The findings suggest that dominant winds shape the orientation of vegetation stripes through a mechanism of neighbouring plants providing wind shelter to downwind individuals.

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Marco Mingione, Francesco Lagona, Priyanka Nagar, Francois von Holtzhausen, Andriette Bekker, Janine Schoombie, Peter C. le Roux. 2024-11-18. Does wind affect the orientation of vegetation stripes? A copula-based mixture model for axial and circular data. https://arxiv.org/abs/2411.11461

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