European User Group March 18 2008 - UrbanSim
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European User Group March 18 2008 - UrbanSim

Recent Developments inOPUS/UrbanSimCenter for Urban Simulation and Policy AnalysisUniversity of WashingtonMarch 18, 2008

Current Projects at CUSPA Integration with Activity-based Modeling – EPA Uncertainty Analysis - NSF Graphical User Interface - Arizona MPOs GIS Integration - Arizona MPOs Real Estate Development - PSRC, Arizona Modeling Travel Behavior - NSF Hierarchical Dynamic Bayesian Networks Discrete Choice

Transition Models (Economic) Current Development Handling of home-based employment, as input to: Home-based job choice model Workplace choice model (non-home-based) Future Priorities Replace with macroeconomic/hybrid model Approaches: Input/Output, Hybrid I/O-Econometric, CGE Preference for dynamic, multi-region, potential for integrationwith microsimulation

Transition Models (Demographic) Future Priorities (now in preliminary planning) Household and person demographic change Aging, births, deaths, split household (child leaves, divorce),merge households Educational attainment Labor market Enter and leave labor market, occupation, part-time, selfemployed Job change

Relocation Models Future Development Change to binary logit (from rate-based probability) Include push factors: current location characteristics Include pull factors: alternative location characteristics Link move and location choice (nested or correlatedchoices) Allow ‘buyers remorse’: back out of a move if options poor

Location Unit in Choice Models Gridcell Efficient for spatial queries Poor for behavioral interpretation – esp. reflecting real estate Parcel More behaviorally realistic Vary in size and shape Building Can be tied to any geography Zone or other Neighborhood Geography Potentially attractive as higher – level Estimation results have generally been poorer

Developer Model Approaches: Site looking for a use Landowner’s problem; highest and best use Land cover or land use transition models Early generation UrbanSim developer model Use looking for a site Developer’s problem; site selection Later version of UrbanSim developer model Hybrid approach current UrbanSim developer model (parcel-level)

Developer Model (Hybrid) Parcel – based Uses Development Templates Project Templates Building Templates Can express wide variety of projects Infill building on single lots Single-family subdivisions Mixed use buildings and projects High-rise development, big-box, strip centers, etc. Could incorporate street patterns… Generates proposals: Filters templates based on land useplan designation on parcel Proposals compete within and across parcels; financing

Developer Model Step 1:Select Parcel for Evaluation

Step 2: Based on Plan Type, EvaluateDevelopment Constraints

Step 3: Constraints Identify AllowedDevelopment TemplatesDevelopment templates can be defined in a number of different ways, includingusing the known development projects as the basis, or general plans, or astatistical analysis of recent developments. PSRC project is using the latter approach.

Step 4: Select Development Proposalsto BuildA hedonic price model predicts the price ofa post-development proposal on the parcel,and subtracts the predicted cost of siteacquisition, and other costs such as sitepreparation, demolition of existing buildings,extension of infrastructure, financing, andother costs that can be incorporated. Thisis used to generate an estimate of theReturn on Investment (ROI) for each proposal.Proposals are selected using a probabilitythat is proportional to their expected ROI.When projects are accepted, they result inDevelopment Projects with status set to‘Active’. These projects are then addedby the Building Construction Model.

Developer Model Current Development Testing and refinement of new algorithms/code Develop inventory of templates Develop visual selection approach for users to identifywhich kinds of development are consistent with plan Improve cost calculations: infrastructure, financing, fees Infill and redevelopment refinements Future priorities Parcel subdivision/consolidation Development risk (real options, e.g. Cunningham)

Workplace Choice Model Replace HBW Trip Distribution Model Move behavior to long-term choice (land use) Discrete choice models Home-based Job Choice Worker chooses to be a home-based job (binary) Aggregate # home-based jobs allocated to HB workers Workplace Choice Model Non-home based workers choose a vacant job Interaction of worker/household and job characteristics

Model System Calibration/Validation Approaches Cross-sectional (as in TRANUS, Dram/Empal, TravelModels) K-Factors internalize errors to match base year Longitudinal calibration/validation (preferred) 1 period to calibrate 2 nd period to validate Bayesian melding approach (Sevcikova, Raftery, Waddell) Will the 90% confidence band on predictions really coverapproximately 90% of the observations? Sensitivity Analysis

Bayesian Melding for CalibratingUncertainty in Model SystemMethod# Cases Missedby 90%ConfidenceIntervalPercentCoveredCasesBayesianMeldingMultipleRuns31 88%163 38%Results from Eugene-springfield - in Transportation Research B, 2007

Open Platform forUrban SimulationOPUS

Integrated VisualizationParcel SizeSeattle Area

Storyboard: Models Once the database is ready to use in modeling, a userwould: Open an existing model system configuration Or create one from an existing template Change configurations as desired Specify models – what variables to use Estimate parameters Create new models (e.g. submodels) Create interfaces to external models (travel models) Run and diagnose models

Storyboard: Indicators Can specify a set of indicators that should be computed As a separate, reusable configuration For a particular model run Requirements: Configure indicators and reportsTypes: maps, charts, tablesPurposes: For diagnosing the models For evaluating outcomes Generate while model is running or after it has completed Generate a batch report, adding charts, maps, and tables into adocument

Storyboard: Running the Model Managing runs of the model: Creating or editing a scenario Starting a run Monitoring progress Examining indicators while the model runs Pausing or stopping a run if needed Browsing through previously run results

Software Architecture for theGUI GUI is implemented in Python using the PyQt UI toolkit The basic chunk of information for configurations in theGUI is a “project” A project is represented for storage and sharing using xml Can be saved in a file, put in an svn repository, etc. Compatibility issue The existing model code uses Python dictionaries forconfigurations GUI uses an adaptor class XMLConfiguration that converts the xmlto the old-style dictionary representation for use with estimationand simulation runs

Inheritance(the implementation of inheritance for xml projects is currentlybeing changed -- this is the new design that should beimplemented soon)A project can inherit from one or more parent projectsCan override any parts of the xml; others inherited from the parentswithout changeFor programming language fans: this is prototype-based rather thanclass-based semanticsUser’s view in the GUI:Contents of parent, grandparent, … projects will be shown in theGUI, but greyed out (read-only)Can click on any node in the xml tree and ask that it be copieddown to the child project; it can then be edited

Priorities forDevelopmentMeeting of MPOs in the US usingUrbanSimMarch 2008

Priorities from Meeting1. Population dynamics/ HH transition2. Base Data synthesis and evaluation tools -Household, Employment synthesizer - Includingcharacteristics (occupation, wage, education,race/ethnicity)3. Neighborhood dynamics/gentrifications -Relocation of households and jobs, change inneighborhood conditions

Priorities from Meeting4. Calibration and validation tools, including backcasting, Easy to use interface to new calibrationtools (BM)5. Multi-tier modeling (sub-markets)- demand/supply balance, internal feedback loops - withswitches6. Dedicated support - tech. support, training (bootcamp), maintenance7. Project templates for help start new project.Documentation-tutorials-user interface

Priorities from Meeting (Lower) Business Evolution Macroeconomic modeling (multi-region) Parallelization

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