A Zone-Based Version of UrbanSim

---

UrbanSim can be configured to run at a Zone Level, Parcel Level or Gridcell Level. This section of the documentation describes the zone level model configuration. By zone, we mean any irregular polygons, from Traffic Analysis Zones used in travel models, to large administrative units such as cities, or small Census Blocks or Neighborhoods. It is up to the user to determine what level of geography fits their needs and data constraints best. The description below is based on the development and initial testing of a zone-level UrbanSim configuration that is being tested, with some variations, in San Antonio, Texas, Durham, North Carolina, and the Puget Sound, Washington.

Given the flexibility of the OPUS platform, it has been relatively easy to adapt the UrbanSim model configurations from the parcel version to work at a zone level. The location_set for the household location choice and employment location choice models are set to building, in both models. But in the zone version of the model, buildings are actually aggregated data, representing the composite of individual buildings that are of the same building_type and in the same zone. So if one defines two housing types, single_family and multi_family, then there will be two residential buildings per zone.

Models in the Zone Version of UrbanSim

Below are the models used in the zone version of UrbanSim. Each model name links to a more detailed description of its objective, algorithm, configuration and data.

Model Name	Abbreviation	Description
Scheduled Development Events Model	SDEM	Handles Scheduled Development Events
Scheduled Employment Events Model	SEEM	Handles Scheduled Employment Events
Real Estate Price Model	REPM	Predicts Price per Unit for Each Building
DevelopmentProjectTransitionModel	DPTM	Predicts New Development Projects to be Located
Residential Development Project Location Choice Model	RDPLCM	Predicts Locations for New Residential Development Projects
Non Residential Development Project Location Choice Model	NRDPLCM	Predicts Locations for New Non-Residential Development Projects
HouseholdTransitionModel	HTM	Adds New Households or Removes Households to Match Control Totals
EmploymentTransitionModel	ETM	Adds New Jobs or Removes Jobs to Match Control Totals
HouseholdRelocationModel	HRM	Predicts Households Decision to Relocate Within Region
HouseholdLocationChoiceModel	HLCM	Predicts Location Choices for New or Moving Households
EmploymentRelocationModel	ERM	Predicts Job (Employer) Decision to Relocate Within Region
EmploymentLocationChoiceModel	ELCM	Predicts Location Choices for New or Moving Jobs
Distribute Unplaced Jobs Model	DUJM	Allocates sectors of employment (e.g. Military) proportionally
Refinement Model	RM	Refine simulation results according to user specified conditions

Data Used in the Zone Version of UrbanSim

---

Script to Generate Database

Table Descriptions

Below is a compilation of all the tables used in the zone version of UrbanSim. Each table name links to a description of the columns within the table. The tables are listed alphabetically.

Table Name	Required	Brief Description
annual_employment_control_totals	Y	Control totals containing the aggregate targets for employment by sector
annual_household_control_totals	Y	Control totals containing the aggregate targets for households by type
annual_household_relocation_rates	Y	Annual relocation rates for households by type
annual_job_relocation_rates	Y	Annual relocation rates for jobs by employment sector
buildings	Y	Aggregated buildings, by building_type and zone
building_sqft_per_job	Y	Non-residential sqft used by each job
building_types	Y	Building types as classified by the user, usually at least 2 residential types and several non-residential types
cities	N	List of cities within the region, primarily for indicators
counties	N	List of counties within the region, primarily for indicators
development_event_history	Y	Development projects that have been built over a historical period of (for example) 10 years
employment_adhoc_sector_groups	N	Aggregations of employment sectors into groups such as basic, retail, service
employment_adhoc_sector_group_definitions	N	Definitions (textual) of ad-hoc sector groups
employment_sectors	Y	Employment sectors, defined by the user as aggregations of an industrial classification, e.g. NAICS or SIC
fazes	N	Optional geographic table that provides a zone aggregation, used mainly for indicators
home_based_status	Y	Indicator table for jobs that are home-based
household_characteristics_for_ht	N	Categories used in control totals
households	Y	Household data, for socioeconomic and density variables
households_for_estimation	N	Households table used in estimation, from a household survey with recent movers, if available
jobs	Y	Employment data, for accessibility and density variables
jobs_for_estimation	N	Jobs table used in estimation, from sample of newly locating jobs, if available
large_areas	N	Optional higher level geography, aggregations of FAZ geography (user-determined), for indicators
race_names	N	Optional names for race groups defined in the synthetic population
target_vacancies	Y	Structural or target vacancies - trigger development when vacancies fall below this
travel_data	Y	Zone-to-zone skims from the travel model, for accessibility variables
zones	Y	Zones used in the travel model, for accessibility and density variables

-- PaulWaddell - 07 Dec 2009

---