They also estimated the dates of the craters.

他们还估计了陨石坑的形成日期。

The researchers used modern measuring equipment and examined tree rings to make estimates dating back as far as the year 800.

研究人员使用现代测量设备，检查了年轮，做出了最早可追溯到公元800年的估计。

In return, the AI compares the case with those in its training data and offers a likely pmi and, therefore, an estimated date of death.

作为回报，AI会将该案例与训练数据中的案例进行比较，并提供可能的pmi，从而推算出死亡日期。