A comparative study of spatial units for walkability assessment in a Brazilian city

Abstract Despite the growing number of research that analyzes the built environment as a support for walking, there are still doubts about the delimitation of the area of influence of this behavior. The use of census tracts is justified by the wide availability of sociodemographic data; however, they have been shown to be fragile for assessing walkability. This article aimed to compare 8 different types of spatial units to verify which ones are better suited to the evaluation of walkability of a Brazilian city, correlating a synthetic walkability index and its component variables with walking frequencies obtained from a recent origin-destination survey. The results showed that the macrozones, the zones of similar sizes (400 m), the grouping by market value, and by topological accessibility showed greater correlations with the levels of walking and that there is a clear dependence of the statistics on the scale of the units and their delimitation, reaffirming the problem of the modifiable areal unit problem (MAUP). The research can contribute to the refinement of spatial methods for walkability assessment, advancing toward a more adequate view of walkability in Brazilian cities.