US Department of Housing and Urban Development, Washington, DC.
Urban Stud. 2011;48(8):1715-737. doi: 10.1177/0042098010375994.
GIS methods are used to construct measures of food access for neighbourhoods in the Portland, Oregon, US metropolitan area and the sensitivity of such measures to methodological variation is examined. The level of aggregation of data inputs is varied and the effect of using both Euclidean and street network distances is tested. It is found that, regardless of the level of geographical disaggregation, distance-based measures generate approximately the same conclusions about the distribution of food access in the area. It is also found that, while the relationship between street network and Euclidean distances varies with population density, measures computed with either construct generate the same relative patterns of food access. These findings suggest that results from food access studies employing disparate methodologies can often be compared.
GIS 方法被用于构建美国俄勒冈州波特兰大都市区社区的食物获取衡量标准，并检验了这些衡量标准对方法变化的敏感性。改变了数据输入的聚合水平，并测试了使用欧几里得和街道网络距离的效果。结果发现，无论地理分散程度如何，基于距离的衡量标准对该地区食物获取分布的结论大致相同。还发现，虽然街道网络和欧几里得距离之间的关系随人口密度而变化，但使用任何一种构建方法计算的衡量标准都会产生相同的食物获取相对模式。这些发现表明，采用不同方法的食物获取研究结果通常可以进行比较。
