publicly available data sets, such as the US Census and land use regulations, to private data sources such as aggregate mobile location or credit transaction data, and real estate transaction data. Whenever possible, Replica measures its model outputs against observed ground-truth, such as auto counts or transit ridership, and publishes the results, in order to provide greater certainty to its customers. Replica customers also have the option to provide their own ground-truth, in order to enable more measurable model outputs.