1. Species sighting records are combined with statistical models to infer whether an endangered species might have become extinct, or instead has just gone unobserved for a lengthy period of time. The challenging part of developing these models lies in dealing with uncertain sightings.
2. We propose a Bayesian hierarchical approach to infer the extinction time of a species based on historical sighting records which may be either certain or uncertain. The posterior distribution for extinction time is evaluated using the likelihood of sighting data and non‐informative priors for model parameters. All the models discussed in this paper are implemented in JAGS, a program for analysing Bayesian models using Markov Chain Monte Carlo (MCMC) simulation.
3. A general methodology is presented and then applied to the sighting record of the ivory‐billed woodpecker (IBW) Campephilus principalis. It was found that the IBW most likely went extinct between 1940 and 1945, a little after the date of the last certain sighting.
4. The methods developed were also applied to other species sighting records as well as some artificial sighting records. Through the results, it was found that the inferred time of extinction is significantly influenced by the last certain sighting if the sighting record consists of only certain sightings. In the presence of uncertain sightings, the inferred extinction time is influenced by either the last certain sighting or the time when the uncertain sighting rate drops.

中文翻译：

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使用贝叶斯方法推断灭绝年份

1. 物种观察记录与统计模型相结合，可以推断出濒临灭绝的物种可能已经灭绝，或者只是长时间没有被观察到。开发这些模型的挑战性部分在于处理不确定的视线。
2. 我们提出了一种贝叶斯分级方法，根据可能是确定的还是不确定的历史目击记录来推断物种的灭绝时间。使用观测数据的可能性和模型参数的非信息先验评估灭绝时间的后验分布。本文讨论的所有模型都在JAGS中实现，JAGS是使用Markov Chain Monte Carlo（MCMC）仿真分析贝叶斯模型的程序。
3. 提出了一种通用方法，然后将其应用于象牙嘴啄木鸟（IBW）的CampephilusPrincipalis的目击记录。人们发现，IBW最有可能在1940年至1945年之间灭绝，那是在最后一次确定目击日期之后不久。
4. 开发的方法还应用于其他物种的目击记录以及一些人工目击记录。通过结果发现，如果目击记录仅由某些目击组成，则推断的灭绝时间会受到最后一次目击的显着影响。在存在不确定的瞄准点的情况下，推断的灭绝时间受最后确定的瞄准点或不确定的瞄准率下降的时间的影响。