An Overview of UrbanSim

Center for Urban Simulationand Policy Analysis

University of Washington

www.urbansim.org

Results of Needs Assessment (in order)

1. Analyze Effects of Land Use on Transportation

2. Analyze Multimodal Assignments

3. Promote Common Use of Data

4. Manage Data Needs

5. Analyze All Modes of Travel

6. Analyze Effects of Land Use Policies

7. Support Visualization Techniques

8. Analyze Effects of Transportation Pricing Policies

9. Analyze Effects of Growth Management Policies

10. Analyze Effects of Transportation on Land Use

Recommendations for New Model Design (made in 2001)

• Model real estate, labor and transportation demand and supply market interactions in an integrated microsimulation framework. Eliminate artificial separation of household choices

• Represent processes at appropriate temporal and spatial detail Real estate and labor markets: annual, parcel Activity and travel: mid-term model effort: 5 daily periods, parcel /

long-term: continuous time

• Integrate and extend recent advances in operational models Disaggregate land use models (Eugene, Honolulu, Salt Lake City) Activity based travel models (San Francisco, Portland)

• Implement as a distributed model system for use by PSRC, cities and counties, state agencies, public with a web-based user-interface

• Implementation plan balancing needs, costs, schedule, and risks

Linked Urban Markets

Governments Infrastructure

Land

FloorspaceHousing

Households BusinessesLabor

Services

Developers

Flow of consumption from supplier to consumer

Regulation or Pricing

Land Use Regulation• Land use plans• Growth managementTransportation• Infrastructure• Pricing

Long-term Choices• Residential Mobility• Housing Choice• Labor Supply• Workplace Choice• Vehicle Ownership

Short-term Choices• Activity Generation• Activity Scheduling• Allocation of Vehicles• Activity Location

Long-term Choices• Mobility• Location Choice• Labor Demand

Short-term Choices• Goods movement

Economic Processes• Economic structure • Output goods/services• Inter-regional trade

Demographic Processes• Ageing• Household structure• Migration

Real Estate Processes• Land development• Housing development• Non-res development• Redevelopment

Households Businesses

Developers

Governments

Long-term Modeling Strategy:Integrated Model of Markets for Real Estate, Labor and

Transportation

An Illustration of the Approach• Consider a major decrease in transport costs• In reality, a household could substitute

among any combination of interdependent changes: Change travel routes, modes, times to take advantage Make more trips Make longer trips to other destinations Move residence to buy more space or amenities farther out Change jobs or enter job market Add a household vehicle

• The proposed model would recognize these as interdependent choices, whereas current models would not

Phased Model Improvements: 2002-5

• Implement Land Use Model based on UrbanSim (current specification) Phase I: Develop database Phase II: Estimate model paramaters Phase III: Test and validate model

system• Integrate with current PSRC models:

STEP macroeconomic model Travel model system

UrbanSim Design Objectives• Support coordinated land use, transportation, and

environmental planning and modeling• Use a transparent behavioral framework• Represent interactions of markets and policies• Represent sufficient detail to support:

Municipal applications; corridor studies Non-motorized transport policies and TOD Environmental and land use policies

• Support trade-off analysis among objectives Efficiency Equity Environmental Impact

• Develop an Open Source modeling platform

UrbanSim Model Design

• Discrete Choice Framework Household Relocation and Location Choice Business Relocation and Location Choice Real Estate Development Explicit Markets for Real Estate

• Governmental policies exogenous: scenarios• Dynamic

Path-dependent (history matters) Supply fixed in short run (one year) Adjustment toward equilibrium in long-run Annual time steps

How is UrbanSim Different?

• Dynamic, non-equilibrium approach• Spatial detail very high• Behavioral approach empirically

measures responses to policies• Focuses visioning on goals and

objectives• Links visioning to planning and

evaluation

JobJOB_ID

GRID_ID

SECTOR_ID

HOME_BASED

SIC

Grid CellGRID_ID

COMMERCIAL_SQFT

GOVERNMENTAL_SQFT

INDUSTRIAL_SQFT

COMMERCIAL_IMPROVEMENT_VALUE

INDUSTRIAL_IMPROVEMENT_VALUE

GOVERNMENTAL_IMPROVEMENT_VALUE

NONRESIDENTIAL_LAND_VALUE

RESIDENTIAL_LAND_VALUE

RESIDENTIAL_IMPROVEMENT_VALUE

RESIDENTIAL_UNITS

YEAR_BUILT

FRACTION_RESIDENTIAL_LAND

PERCENT_UNDEVELOPABLE

TOTAL_NONRES_SQFT

DEVELOPMENT_TYPE_ID

DISTANCE_TO_ARTERIAL

DISTANCE_TO_HIGHWAY

RELATIVE_X

RELATIVE_Y

PLAN_TYPE_ID

PERCENT_WATER

PERCENT_WETLAND

PERCENT_STREAM_BUFFER

PERCENT_FLOODPLAIN

PERCENT_SLOPE

PERCENT_OPEN_SPACE

PERCENT_PUBLIC_SPACE

PERCENT_ROADS

IS_OUTSIDE_URBAN_

GROWTH_BOUNDARY

IS_INSIDE_NATIONAL_FOREST

IS_INSIDE_TRIBAL_LAND

IS_INSIDE_MILITARY_BASE

ZONE_ID

CITY_ID

COUNTY_ID

PERCENT_AGRICULTURAL_

PROTECTED_LANDS

ACRES

HouseholdHOUSEHOLD_ID

GRID_ID

PERSONS

WORKERS

AGE_OF_HEAD

INCOME

CHILDREN

RACE_ID

CARS

Key Model Components

• Household and Employment Location Standard multinomial logit Grid cell is unit of choice

• Real Estate Development Multinomial logit 24 development type outcomes

• Real Estate Price Estimation Hedonic regression

Data Inputs

• Regional Control Totals• Parcel Data• Business Establishments• Household Data (Census, Travel Survey)• Land Use Plan/Zoning• Environmental Features• Public Land ownership

Residential Location Variables

• Housing Characteristics Prices (interacted with income) Development types (density, land use mix) Housing age

• Regional accessibility Job accessibility by auto-ownership group Travel time to CBD and airport

• Urban design-scale (local accessibility) Neighborhood land use mix and density Neighborhood employment

Employment Location Variables

• Real Estate Characteristics Prices Development type (land use mix, density)

• Regional accessibility Access to population Travel time to CBD, airport

• Urban design-scale Proximity to highway, arterials Local agglomeration economies within &

between sectors: center formation

Development Variables

• Site characteristics Existing development characteristics Land use plan Environmental constraints

• Urban design-scale Proximity to highway and arterials Proximity to existing development Neighborhood land use mix and property values Recent development in neighborhood

• Regional Access to population and employment Travel time to CBD, airport

Land Price Variables

• Site characteristics Development type Land use plan Environmental constraints

• Regional accessibility Access to population and employment

• Urban design-scale Land use mix and density Proximity to highways and arterials

UrbanSim – Travel Model Interactions

UrbanSimTravel Models

Households by Income Age of head Size Workers ChildrenEmployment by sector

Composite Utility by Auto OwnershipHighway Travel TimesVehicle Ownership Probabilities

Creating Policy Scenarios

• Macroeconomic Assumptions Household and employment control totals

• Development constraints Can select any combination of

• Political and planning overlays• Environmental overlays• Land use plan designation

Constraints determine which development types cannot be built

• Transportation infrastructure• User-specified events

Puget SoundRegional Council

4 Counties72 Cities3 PortsWS Dept of TranspWS Transp Comm also: 6 transit agencies 6 Associate Members 2 adjacent counties 2 tribes 1 port Evans School of Public Affairs, UW

Seattle

Everett

Bremerton

Tacoma

Bellevue

SNOHOMISH

KING

PIERCE

KITSAP

Population: 3,275,847Area: 6,287.8 sq mi

Seattle

Everett

Bremerton

Tacoma

Bellevue

SNOHOMISH

KING

PIERCE

KITSAP

Puget SoundRegional Council

Population: 3,275,847Area: 6,287.8 sq mi

Urban Growth AreaPopulation: 2,804,125Area: 980.1 sq mi

Seattle

Everett

Bremerton

Tacoma

Bellevue

SNOHOMISH

KING

PIERCE

KITSAP

Puget SoundRegional Council

Major Steps in Data Preparation1. Determine study area boundary2. Generate grid over study area3. Assemble and standardize parcel data4. Impute missing data on parcels5. Assemble employment data6. Assign employment to parcels7. Convert Parcel data to grid8. Convert other GIS layers to grid9. Assign Development Types10.Synthesize household database11.Diagnose data quality and make

refinements12.Document data and process