Volunteered geographic information (VGI) has great potential to reveal spatial and temporal dynamics of geographic phenomena. However, a variety of potential biases in VGI are recognized, many of which root from volunteer data contribution activities. Examining patterns in volunteer data contribution activities helps understand the biases. Using eBird as a case study, this study investigates spatial and temporal patterns in data contribution activities of eBird contributors. eBird sampling efforts are biased in space and time. Most sampling efforts are concentrated in areas of denser populations and/or better accessibility, with the most intensively sampled areas being in proximity to big cities in developed regions of the world. Reported bird species are also spatially biased towards areas where more sampling efforts occur. Temporally, eBird sampling efforts and reported bird species are increasing over the years, with significant monthly fluctuations and notably more data reported on weekends. Such trends are driven by the expansion of eBird and characteristics of bird species and observers. The fitness of use of VGI should be assessed in the context of applications by examining spatial, temporal and other biases. Action may need to be taken to account for the biases so that robust inferences can be made from VGI observations.

中文翻译：

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志愿者数据贡献活动中的时空格局：以eBird为例

自愿地理信息（VGI）具有揭示地理现象的时空动态的巨大潜力。但是，人们已经认识到VGI的各种潜在偏见，其中许多源于志愿者数据贡献活动。检查志愿者数据贡献活动中的模式有助于理解偏见。本研究以eBird为例，研究了eBird贡献者的数据贡献活动中的时空格局。eBird采样工作在时空上存在偏差。大多数采样工作都集中在人口稠密和/或交通便利的地区，而采样最密集的区域则位于世界发达地区的大城市附近。报告的鸟类种类在空间上也偏向需要更多采样工作的区域。暂时 多年来，eBird的抽样工作和报告的鸟类种类都在增加，每月波动很大，周末报告的数据更多。这种趋势是由eBird的扩展以及鸟类和观察者的特征所驱动的。应通过检查空间，时间和其他偏差，在应用环境中评估使用VGI的适用性。可能需要采取措施来考虑偏差，以便可以从VGI观察中得出可靠的推论。时间和其他偏见。可能需要采取措施来考虑偏差，以便可以从VGI观察中得出可靠的推论。时间和其他偏见。可能需要采取措施来考虑偏差，以便可以从VGI观察中得出可靠的推论。