ABSTRACT Wedding mobile phone sensor technology and human spatial behaviour has great potential. The ubiquity of Global Positioning Systems (GPS) technology has made gathering data about human mobility simpler, more precise, and with higher fidelity, providing minute-by-minute records of the locations of cohorts from dozens of participants. While this data provides a strong basis for Geographic Information Science research, it also constitutes an invasion of the participants’ privacy and can provide more information than researchers require to answer their questions. As an ethical and practical consideration, researchers should gather only as much data as they need. In this paper, we take three weeks of GPS traces from over a hundred student participants in mobile phone-based tracking studies and show that fewer than 14 days of data is necessary to establish complete activity spaces. We define ‘complete’ as the point at which marginal information gains become negligible according to a pairwise temporal analysis of the Kullback–Leibler (KL) divergence of the spatial (bivariate) histogram through time. For the fixed level of information difference, observable in the data, impacts due to individual variability, population composition, and spatial resolution are evident. However, all populations at each level of resolution examined in the paper demonstrated convergence to low divergence levels occurred within a matter of days, and to negligible information gain in less than two weeks. The methods described in the paper represent a novel metric useful to understand the interaction between measurements and information in human mobility.

中文翻译：

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多少天足够？：捕捉日常的人类活动

摘要 婚礼手机传感器技术和人类空间行为具有巨大潜力。无处不在的全球定位系统 (GPS) 技术使得收集有关人类移动性的数据变得更简单、更精确、保真度更高，可提供来自数十名参与者的队列位置的每分钟记录。虽然这些数据为地理信息科学研究提供了强有力的基础，但它也构成了对参与者隐私的侵犯，并且可以提供比研究人员回答问题所需的更多信息。作为道德和实际考虑，研究人员应该只收集他们需要的数据。在本文中，在基于手机的跟踪研究中，我们从 100 多名学生参与者那里获取了三周的 GPS 跟踪数据，结果表明，建立完整的活动空间所需的数据不到 14 天。根据空间（双变量）直方图随时间的成对时间分析，我们将“完整”定义为边际信息增益可以忽略不计的点。对于固定水平的信息差异，数据中可观察到的个体变异性、种群组成和空间分辨率的影响是显而易见的。然而，论文中检查的每个分辨率级别的所有群体都表明，在几天之内就会收敛到低发散水平，并在不到两周的时间内收敛到可以忽略不计的信息增益。