Application of Trip and Vehicle Elasticities to Households by Place Type

Is there  documentation on how trip and vehicle elasticities are applied to households based on place types?  It appears there is an adjustment to 5D levels by place type (place_type_relative_values.csv). How can one understand the computation process? E.g. are the elasticites applied to a scenario’s “trips” or to the “difference in trips” between two scenarios?