标题： 广义隔离-迁移模型：多位点数据集的最大似然实现 显示英文标题

标题： The Generalised Isolation-With-Migration Model: a Maximum-Likelihood Implementation for Multilocus Data Sets

摘要： 关于物种形成过程的统计推断通常基于隔离与迁移（IM）模型，尤其是在研究目的是了解分化过程中基因流的存在或缺失时。本文介绍的广义IM模型扩展了标准的两群体IM模型和隔离与初始迁移（IIM）模型，并将这两个模型作为特例包含在内。它可以描述为一个两群体IM模型，在过去某个时间点允许迁移率和种群大小发生变化。通过开发这种GIM模型的最大似然实现，我们能够对两个密切相关的物种之间的历史和当代基因流速率进行推断。我们的方法依赖于共现生成矩阵的谱分解，并适用于由大量独立位点上每对DNA序列之间的核苷酸差异数组成的数据集。 显示英文摘要

摘要： Statistical inference about the speciation process has often been based on the isolation-with-migration (IM) model, especially when the research aim is to learn about the presence or absence of gene flow during divergence. The generalised IM model introduced in this paper extends both the standard two-population IM model and the isolation-with-initial-migration (IIM) model, and encompasses both these models as special cases. It can be described as a two-population IM model in which migration rates and population sizes are allowed to change at some point in the past. By developing a maximum-likelihood implementation of this GIM model, we enable inference on both historical and contemporary rates of gene flow between two closely related species. Our method relies on the spectral decomposition of the coalescent generator matrix and is applicable to data sets consisting of the numbers of nucleotide differences between one pair of DNA sequences at each of a large number of independent loci.