Adaptive sampling in space and time

该研究发展了空间和时间自适应采样的理论和方法。 适应性抽样设计是指抽样单位的选择取决于调查过程中观察到的感兴趣变量的值。 适应性设计可以为空间聚集的、稀有的和网络化的种群提供显著的效率提高。拟议的研究领域之一是调查和开发自适应抽样设计，其中抽样单位可能会在调查过程中移动。 为了对空间分布的群体进行采样，采样单元通常被认为是感兴趣区域的固定点或子集。 然而，对于在空间和时间上分布的总体，考虑单位随时间推移在空间中移动的采样路径是有意义的。 在这种情况下，采样单元是空间/时间中的路径、流形或子区域。 例如，为了用有限数量的传感器单元监测急性空气污染物云的意外释放，使单元沿主要垂直于风的路径移动是最有效的。 类似的路径考虑也适用于使用船只或飞机对迁徙动物进行调查。 更复杂的动态抽样计划适用于通过社交网络监测流行病进展的设计。 将研究自适应移动设计，其中路径可以改变或新的路径被添加到响应于观察值。拟议研究方案的其他领域包括在自然和人类群体中进行适应性干预或实验，适应性设计理论，以及利用特殊人口结构的新适应性设计。 该研究对健康和环境科学等领域具有重要的应用价值。

The proposed research develops theory and methods of adaptive sampling in space and time.  Adaptive sampling designs are those in which the selection of the sample units depends on values of variables of interest observed during the course of the survey.  Adaptive designs can offer substantial increases in efficiency for spatially clustered, rare, and networked populations. One area of the proposed research investigates and develops adaptive sampling designs in which the sampling units may move during the course of the survey.  For sampling spatially distributed populations, a sampling unit is typically conceived to be a fixed point or subset of the region of interest.  For populations distributed in space and time, however, it makes sense to consider sampling paths on which units move through space over time.  In this case, a sampling unit is a path, manifold, or subregion in space/time.  For example, to monitor for surprise releases of acute air pollutant clouds with a limited number of sensor units, it is most efficient to have units moving in paths that are predominantly perpendicular to the wind.  Similar path considerations may apply to surveys of migratory animals using boats or aircraft.  More complex dynamic sampling plans apply to designs for monitoring the progress of epidemics through social networks.  Adaptive moving designs in which the paths can change or new paths be added in response to observed values will be investigated. Other areas of the proposed research programme include adaptive interventions or experiments in natural and human populations, theory of adaptive designs, and new adaptive designs to take advantage of special population structures.  The proposed research has important applications to the health and environmental sciences and other fields.