City planners have a professional and ethical responsibility to provide public goods equitably. Parks improve mental and physical health by nurturing social cohesion and enabling physical activity. So who gets parks? Park access has traditionally been evaluated using constructed variables of potential access: distances, buffers, and gravity models. These models have major limitations: they ignore commutes and other more intricate mobility behaviors. To address these issues, I propose a nationally scalable, empirical measure of realized use. Using a dataset of smartphone locations, I identify visits to parks in the 20 largest American cities. I use these data to calibrate existing models, and then contrast the models with realized use. The spatial models are not simply imprecise; they systematically over-estimate realized access by minority populations. In other words, they understate inequity.

中文翻译：

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美国城市公园使用的实证测量，以及空间模型的人口偏差

城市规划者有专业和道德责任来公平地提供公共产品。公园通过培养社会凝聚力和促进体育活动来改善身心健康。那么谁得到公园呢？传统上，公园使用权是使用构建的潜在变量来评估的访问：距离、缓冲区和重力模型。这些模型有很大的局限性：它们忽略了通勤和其他更复杂的移动行为。为了解决这些问题，我提出了一种在全国范围内可扩展的、经验性的已实现使用量度。使用智能手机位置数据集，我确定了美国 20 个最大城市的公园访问量。我使用这些数据来校准现有模型，然后将模型与实际使用进行对比。空间模型不仅仅是不精确的；他们系统地高估了少数群体实际获得的机会。换句话说，他们低估了不平等。