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bioRxiv · 10.64898/2025.12.22.695918

Notes on f4-ratio estimation

Leppala, K.
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Abstract

The f4-ratio estimation is a popular technique for estimating gene flow proportion as a ratio between two f4-statistics. We point out the underappreciated fact that the root is not important in f4-ratio estimation, making the technique highly versatile. We study robustness and the bidirectional case. We introduce an enhanced branch statistic fB for detecting tentative gene flow events in a large phylogenetic tree, which has favourable properties compared to Malinskys branch statistic fb.

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Leppala, K.. 2025-12-24. Notes on f4-ratio estimation. https://doi.org/10.64898/2025.12.22.695918

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