Undetected extinctions constitute a portion of biodiversity loss that is often ignored. We compared the performance of two models of undetected extinctions - Tedesco and SEUX - when estimating undetected extinctions with both simulated and real-world data. We generated simulated data by considering a birth-death process where less abundant species are more likely to go extinct. When we assumed that detection rates are higher for common species, the two models underestimated the true number of undetected extinctions; when we assumed that detection rates were independent of abundance, the two models, especially the SEUX model, performed better. This confirms that the key assumption required for the models to give accurate estimates is that detection and extinction rates are uncorrelated across species. We tested this assumption using a logistic regression on eight real-world datasets, finding that we could reject the assumption for three of them but not for the others. The two models estimated that true extinctions may be anywhere from 15% to 180% higher than observed values. For six of the eight datasets, the SEUX model gave values that were lower than those of the Tedesco model. We mainly attributed this difference to the SEUX model's assumption that there are no undetected extant species in the present day. Despite caveats associated with the models, the evidence from both points in the same direction: biodiversity loss in these groups may be more severe than what has been documented. Article impact statement: Two undetected-extinction models agree on relative magnitudes of hidden biodiversity loss, but their applicability is context dependent. This article is protected by copyright. All rights reserved.

中文翻译：

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量化两个未检测到的灭绝模型的相对性能

未被发现的灭绝构成了经常被忽视的生物多样性丧失的一部分。我们比较了两种未检测到灭绝模型的性能 - Tedesco 和 SEUX - 在使用模拟和现实世界数据估计未检测到的灭绝时。我们通过考虑生灭过程来生成模拟数据，在这个过程中，数量较少的物种更有可能灭绝。当我们假设常见物种的检测率较高时，这两个模型低估了未被检测到的灭绝的真实数量；当我们假设检出率与丰度无关时，两个模型，尤其是 SEUX 模型，表现更好。这证实了模型给出准确估计所需的关键假设是发现率和灭绝率在物种之间不相关。我们在八个真实世界的数据集上使用逻辑回归测试了这个假设，发现我们可以拒绝其中三个的假设，但不能拒绝其他人的假设。这两个模型估计，真正的灭绝可能比观测值高 15% 到 180%。对于八个数据集中的六个，SEUX 模型给出的值低于 Tedesco 模型的值。我们主要将这种差异归因于 SEUX 模型的假设，即当今没有未被发现的现存物种。尽管与模型相关的警告，但来自同一方向的两个点的证据：这些群体的生物多样性丧失可能比记录的更严重。文章影响声明：两种未被发现的灭绝模型就隐藏的生物多样性丧失的相对幅度达成一致，但它们的适用性取决于上下文。本文受版权保护。版权所有。