The Role of Data Sample Uncertainty in Delineations of Core Based Statistical Areas and Rural Urban Commuting Areas

• Published in: Spatial demography Vol. 11; no. 2
• Main Authors: Fowler, Christopher S., Cromartie, John
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.08.2023; Springer Nature B.V
• Subjects: Commuting; Delineation; Demography; Geographical Information Systems/Cartography; Humanities; Law; Regional/Spatial Science; Rural areas; Social Sciences; Statistics; Statistics for Social Sciences; Surveys; Uncertainty; Rural; Uncertainty; Metropolitan
• ISSN: 2364-2289; 2164-7070
• DOI: 10.1007/s40980-023-00118-4

Federal standards that assign counties to Core Based Statistical Areas (CBSAs) and designate tracts with a Rural Urban Commuting Area (RUCA) code rely on journey to work data from the American Community Survey (ACS). Because the ACS is based on a relatively small sample of the population commuting flows are represented as point estimates, frequently with high margins of error. In this paper we examine the impact of uncertainty in commuting flows on these two critical designations. We find that, for the vast majority of counties (85%) and tracts (87%), the official designation remains consistent and that, in over 1,000 replications of the data, 98% of county assignments and 97% of tract assignments were consistent with the official delineations. While these results are reassuring, a small number of counties and tracts do experience assignments that are different from the official delineation at very high rates. We also test the official delineations against an alternative data source, the Longitudinal Employer- Household Dynamics Survey’s Origin–Destination Employment Statistics (LEHD-LODES). We find the LODES data result in designations that are largely consistent with those from the ACS but we lack a clear way to choose between the data products in places where they differ. Overall, our findings suggest that the current delineation method for assigning counties to CBSAs and tracts to RUCA codes is sufficiently robust to uncertainty to continue going forward. Nevertheless, the presence of significant uncertainty for some observations suggests the need for continued consideration of uncertainty in the context of future data releases.