Toward Quantitative Geocode Accuracy Metrics

Existing geocode quality metrics provide little utility for those interested in the spatial uncertainty associated with a geocoded location. The per-geocode metrics describe aspatial characteristics of individual aspects of the geocoding process, while the per-dataset spatial metrics provide only general information that may not apply to a single geocode of interest. In this paper we develop a method for describing the certainty of a geocoded datum as a spatial probability surface based on an uncertainty propagation model which takes into account the certainty stemming from each portion of the geocoding process. This surface-based geocode output structure provides a more truthful view of the uncertainty present in these data and will enable more realistic estimates of information derived from them in such tasks as environmental exposure modeling.