Dougherty Eric R, de Valpine Perry, Carlson Colin J, Blackburn Jason K, Getz Wayne M
1Environmental Science, Policy & Management, University of California, Berkeley, USA.
2National Socio-Environmental Synthesis Center, University of Maryland, Annapolis, USA.
Mov Ecol. 2018 Jul 12;6:10. doi: 10.1186/s40462-018-0128-2. eCollection 2018.
Continued exploration of the performance of the recently proposed cross-validation-based approach for delimiting home ranges using the Time Local Convex Hull (T-LoCoH) method has revealed a number of issues with the original formulation.
Here we replace the ad hoc cross-validation score with a new formulation based on the total log probability of out-of-sample predictions. To obtain these probabilities, we interpret the normalized LoCoH hulls as a probability density. The application of the approach described here results in optimal parameter sets that differ dramatically from those selected using the original formulation. The derived metrics of home range size, mean revisitation rate, and mean duration of visit are also altered using the corrected formulation.
Despite these differences, we encourage the use of the cross-validation-based approach, as it provides a unifying framework governed by the statistical properties of the home ranges rather than subjective selections by the user.
对最近提出的基于交叉验证的方法使用时间局部凸包(T-LoCoH)方法划定活动范围的性能进行持续探索,发现了原始公式存在的一些问题。
在此,我们用基于样本外预测的总对数概率的新公式取代了临时交叉验证分数。为了获得这些概率,我们将归一化的LoCoH包络解释为概率密度。此处描述的方法的应用导致最优参数集与使用原始公式选择的参数集有显著差异。使用校正后的公式,得出的活动范围大小、平均重访率和平均访问持续时间的指标也会改变。
尽管存在这些差异,我们仍鼓励使用基于交叉验证的方法,因为它提供了一个由活动范围的统计属性而非用户主观选择所支配的统一框架。