Okamura Hiroshi, Kitakado Toshihide, Hiramatsu Kazuhiko, Mori Mitsuyo
National Research Institute of Far Seas Fisheries, 5-7-1 Orido, Shimizu, Shizuoka 424-8633, Japan.
Biometrics. 2003 Sep;59(3):512-20. doi: 10.1111/1541-0420.00061.
In conventional line transect theory, it is assumed that all animals on the line are detected. This article introduces an extended and generalized hazard probability model without the need for such an assumption. The proposed method needs a survey design with independent observers having the same visual region and assumes an explicit distinction of simultaneous and delayed duplicates. It can take account of random heterogeneity caused by surfacing behavior as well as systematic heterogeneity by covariate effects. Furthermore, it can be easily extended to cases in which data from incompletely independent observers are available. The abundance estimate is based on the Horvitz-Thompson estimator in unequal detectability sampling scheme. Simulation studies suggest that the proposed method has good performance. The method is applied to a real data set on Antarctic minke whales in the illustration.
在传统的线截理论中，假定线上的所有动物都能被检测到。本文引入了一种扩展的广义风险概率模型，无需这种假定。所提出的方法需要一个调查设计，其中独立观察者具有相同的可视区域，并假定能明确区分同时出现和延迟出现的重复个体。它可以考虑由浮出水面行为引起的随机异质性以及协变量效应导致的系统异质性。此外，它可以很容易地扩展到有来自不完全独立观察者的数据的情况。丰度估计基于不等可探测性抽样方案中的霍维茨 - 汤普森估计量。模拟研究表明所提出的方法具有良好的性能。在示例中，该方法被应用于一个关于南极小须鲸的真实数据集。
