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Abstract BackgroundProximity to food sources is one of the quantifiable factors measurable across space impacting diet-related health outcomes. Contemporary research has coined the terms ‘food desert’ and ‘food swamp’, sometimes combined with a poverty component, to highlight disproportionate access to healthy and unhealthy food sources. However, there are various ways to measure this proximity—i.e., food availability in this research. Dollar stores such as Dollar General, Family Dollar, and Dollar Tree are one emerging facet of the food environment that provides healthy and unhealthy food options yet have not fully been studied. With more ways to easily measure food availability within the confines of a GIS, this paper proposes a new raster-based Point Density metric to measure the availability of these Dollar stores. In this study, this raster-based metric was calculated for a 6-county region in central North Carolina and compared to six other availability metrics utilized in food security research. A novel Python-based tool to compute the Jaccard Index between these various availability metrics and a matrix to compare these pairwise Jaccard Index calculations was created for this raster-based metric, which is very easy to derive. ResultsUsing a pairwise Jaccard Index summarized and then averaged in a correlation table, the Point Density measure rated the highest (.65) when compared to 6 other popular vector-based techniques. Our results showed the density metric performed statistically better than Euclidean distance, drive-time, density, and point-in-polygon vector metrics when measuring availability for Dollar stores in Central North Carolina. ConclusionsResults reinforce the efficacy of this easy-to-compute metric comparable to vector-based counterparts that require more robust network and/or geoprocessing calculations. Results quantitatively evaluate food availability with an eventual goal of dictating local, regional, and even state-level policy that critically and holistically consider this metric as powerful and convenient metric that can be easily calculated by the lay GIS user and understood by anyone.
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This content will become publicly available on December 1, 2025
Measuring post-disaster accessibility to essential goods and services: proximity, availability, adequacy, and acceptability dimensions
Abstract Rapid restoration of access to essential goods and services has long been regarded as paramount for community recovery. Yet, there remains ambiguity in how access should be defined, measured, or operationalized. Defining accessibility as the ability to use available goods and services with a reasonable level of effort and cost requires evaluating it across six dimensions (proximity,availability,adequacy,acceptability,affordability, andawareness) while considering the perspective of both users and providers in the evaluation. But common distance-based metrics that focus solely on physical access and travel time often fall short of fully capturing these requirements, overlooking the user's perception. This paper introduces a new spatio-temporal accessibility metric that combines four out of these six dimensions, including proximity, acceptability, adequacy, and availability. The metric considers uncertainty in measuring each dimension and addresses both user and provider perspectives in measuring the acceptability and adequacy dimensions. The variation in the metric across the disaster timeline serves as a proxy for community recovery. The metric aligns with common engineering-oriented functionality-based resilience frameworks as the functionality level of the providers has been incorporated in its development. Operating at the household level, the metric determines the ratio of post-disruption access time to the intended good or service against its pre-disruption access time and yields a unitless ratio between zero and one, with zero expressing a total loss in accessibility and one signifying the same level of accessibility as pre-disruption. The proposed metric, while being scientifically principled, is a practical tool whose output is easily understood even by non-expert individuals. The metric is illustrated for schools and pharmacies using the Lumberton Testbed and data collected following the 2016 flood in Lumberton, North Carolina after Hurricane Matthew. Findings provide new insight into recovery plan prioritization and can be used to trigger protective actions. The paper concludes by discussing issues and barriers related to developing and validating accessibility metrics while highlighting areas for future research.
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- Award ID(s):
- 1847373
- PAR ID:
- 10566120
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of Infrastructure Preservation and Resilience
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2662-2521
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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