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bioRxiv · 10.1101/2024.09.19.613917

The TMRCA of general genealogies in populations of variable size

Wemces, A. H.·Penaloza, L.·Steinruecken, M.·Siri-Jegousse, A.
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Abstract

We study the time to the most recent common ancestor (TMRCA) of a sample of finite size in a wide class of genealogical models for populations with deterministically varying size. This is made possible by recently developed results on inhomogeneous phase-type random variables, allowing us to obtain the density and the moments of the TMRCA of time-dependent coalescent processes in terms of matrix formulas. We also provide matrix simplifications permitting a more straightforward calculation. With these results, the TMRCA provides an explanatory variable to distinguish different evolutionary scenarios, and to infer model parameters.

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Wemces, A. H., Penaloza, L., Steinruecken, M., Siri-Jegousse, A.. 2024-09-24. The TMRCA of general genealogies in populations of variable size. https://doi.org/10.1101/2024.09.19.613917

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