C. Lakin of the University of Minnesota, a deinstitutionalization researcher, has indicated that a taxonomy of residential facilities for individuals with intellectual disabilities includes program model, size and operator, and facilities also then vary by disability and age, among other primary characteristics.Prior residential facility classifications were described by Scheerenberger until the modern day classification by David Braddock on a state-by-state basis which includes individuals in residential settings of six or fewer, one categorical group.