Data and representation - UrbanSim

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Data and representation - UrbanSim

Notes on the SanFranciscoUrbanSimImplementationData and representationMay 27, 2010


Primary use• Environmental impact reports of plans, projects andprograms• Eastern Neighborhoods Rezoning, Market & Octavia,Candlestick Point Secondary use• Serves as yardstick against regional housing needsassessments• Strategic growth assessments (where, what and howmuch?)• Countywide transportation plan, Sustainable CommunityStrategy


Conceptual and mathematical robustness• Reflects actual agent choices• Potentially infinite indicators within the model domain =flexibility• More substantive questions of policy can be addressed Open source = city can take “ownership” after consultantleaves Modular architecture:• Configurable, tweakable• Adding new models on the fly Has a considerable user community


City is, with its 49 square miles, still struggling with itsland use futures• Should the city keep industrial zoning? How much? Where?• Can the city meet, and how, the countywide control totals?• Should we as planners try to upzone downtown peripheryfor high rises, or go for more decentralized campus-styledevelopment? Which policy has which effect on average residential orcommercial prices?


Model is parcel-based Advantages of parcel geography• Finer grained analysis• Conceptually intuitive Disadvantages• The finer the scale, the more uncertainty• Can lead to misleading interpretations for specific parcels• Odd parcel size distribution


ModelComment1) process_pipeline_events Pipeline projects2) real_estate_price_model3) building_transition_model4) building_location_choice_modelDevelopment model. Samples recentdev.Sampled buildings, by type (residentialand commercial) placed on parcels withremaining capacity.5) Household_transition_model Households. Population is an attribute6) Business_transition_model Match job control by 11 industry groups7) household_relocation_model Households to relocate8) household_location_choice_model9) business_relocation_model Businesses to relocate10) business_location_choice_model


DataParcelsBuildingsReal Estate Transactions (sales,development)SourceCity maintains dataset with minimalattributesCity does not maintain; attributesextracted from parcel setAssessor's data, pipeline data,(third party lease data, rent data)BusinessesThird party vendors (D&B, ES-202)PopulationSynthesized from PUMS dataHouseholdsSynthesized from PUMS data


Planning and Building are separate departments and have separate casetracking databases• Legacy problems• Different/incompatible schemas—actual project tracking difficult• Data coordination is incidental• Buildings lack proper (GIS) representation• Multi-year multi-agency effort of consolidating permit services and interface inthe works Therefore..• A comprehensive data model relating buildings and parcels is lacking• New pipeline data is consolidated from Planning and Building databases• Building footprints was recently acquired via LiDAR but not yet integratedinto a meaningful parcel data model• A key statistic, vacancy, is inferred based on different external andinternal data sources and is often incorrect/out of bounds at the parcellevel


Use, not industry is generator of trip activity in SFCHAMPtravel model• Each use type has different trip generating properties• Commercial• Management, information, and Professional Services• Cultural/lnstitution/Education (CIE)• Retail/Entertainment• Production/Distribution/Repair (PDR)• Medical and Health Services• Visitor Lodging• Residential• Households by type• Employed residents


Business Transition Model= New JobsBusiness LocationChoice ModelReal EstatePricesVacancy RatesBuilding LocationChoice ModelBuilding TransitionModel


Financial services is an industry A Building might be classified as industrial or office Office is, in effect, a land use activity A financial services company may have an office in a“industrial” or even a retail building Which do you represent in a model?• Economic transition model matches industry targets• Business location choice uses activities• Building transition model matches targets by building types Planning Code prescribes activities, not industries• Activity is thus codified at parcel level What use is a company in the mining industry?


Business “land use sectors” (now “activities”)CIE - Civic, Institutional & Educ. PDR - Production, Dist. & RepairMED - MedicalRETAIL/ENT - Retail & Entertainm.MIPS - Mgmt., Info. & Prof. Svcs VISITOR - Hotels & LodgingBuilding “uses” (deprecated)APTS - ApartmentsCIE - Civic, Institutional &EducationalCONDO - CondominiumsFLATS - Tenants in CommonLIVEWORK - Residence & StudioLoftsMED - MedicalMIPS - Mgmt., Info. & Prof.ServicesMIXED - Mixed use non-residentialMIXEDRES - Mixed use with resid.OPENSPACE – ParksPAPERLOT - Not a buildingPDR - Production, Dist, & RepairRETAIL/ENT – Retail &EntertainmentROW - Right of waySINGLE - Single familySRO - Single room occupancyVACANT - Not a buildingVISITOR - Hotels & Lodging


Retail SalesandServices712.40 Other Retail § 790.102 P # P # P #Sales andServices[Not ListedBelow]712.41 Bar § 790.22 P P712.42 Full-Service § 790.92 P PRestaurant712.43 Large Fast § 790.90 C # C #FoodRestaurant712.44 Small Self- § 790.91 P # P #ServiceRestaurant712.45 Liquor Store § 790.55712.46 MovieTheater§ 790.64 P PEach use code is mapped to activity


submodel Observations R-SquaredAdjusted R-Squaredt-valueapartment 12,733 0.39 0.38 3.07automotive 267 0.51 0.50 2.36commercial 3,137 0.47 0.47 2.84condo 5,093 0.59 0.59 2.92flat 20,348 0.08 0.08 3.15hotel 725 0.63 0.63 2.57industrial 2,331 0.48 0.48 2.78institutional 828 0.62 0.62 2.59mixed 3,183 0.28 0.28 2.84office 1,250 0.72 0.71 2.67other 894 0.40 0.40 2.61res_other 441 0.32 0.30 2.47single 95,702 0.14 0.14 3.39


MIPS submodel, Adj. rho-squared: 0.424618968284


Use Jobs SF Estab.CIE 15 7,713 3MED 2 5,414 1MIPS 91 55,758 15RETAILENT 235 126,400 6Total 343 195,285 25 CoStar: 56,400 SF Class B OfficeBuilding, multiple tenants Assessor: Industrial Building,square footage missing value Planning Estimate (LiDAR):67,625 SF Planning Capacity Estimate perzoning, height, lot size: 67,824 SF Dun & Bradstreet – table What’s a planner to use? Further:• Building is mixed use• Represent as a “mixed use”type with its own estimation, or• Break out each unique use into“virtual” buildings parts?


Develop scenario datasets to test land use impact ofcentral subway expansion—great chance to testinteraction with travel model Have price model reflect building-level vacancy so emptybuildings will be priced at a discount Consider the relation between building types and localeconomies


A great model requires good data—we will hire Anubhav! Getting sufficient resolution and accuracy in base year data• Vacancy by building type grouping Representing economic transactions• Assessed values and Prop 13• Sales, rather than leases• TIC transfers technically not a sale for assessment purposes• Rental and commercial occupancy data Capacity Data• Artificial distinction between res and com Home-based employment—now a stopgap fix Explicit redevelopment representation Business job growth model


Issue: Capacity data over-estimation


Issue: Removal of households in Marina District where wejust saw units addedUseful to check as an indicator vacancy of individual buildings


Issue: Decrease in Avg Unit Price, Many TAZs


Issue: Home based jobs at base year removed


Regional / County Forecast (HENRY)County Employment DisaggregationCounty-Level Demographic ComponentMigration / Commuting ComponentZone Level Allocation (POLIS Model)Census Tract Allocation (SAM)


On Base Year Database Dot com days moved epicenter of growth Long Range Planning Section of the PlanningDepartment minimal in late 1990s A need in long range planning section to have meaningfuldatasets and time series Industrial lands debate; loss of industrial lands…we think From assessor’s data, we have building type information(static property) We were missing a more substantive use classification• Residential• Commercial (relatively disaggregate)


Target schema determined by travel model• {Office, Retail, Cult/Inst/Educ/, Prod/Distrib/Repair, Medical,Visitor}• Sectors aggregation of land use codes per Planning Code• Land use activities trigger trips by residents in households• However, for trip purposes TAZs act as abstraction /aggregation layer• Households are not matched with individual jobs—some areheld by folks commuting into city, while some households workoutside city


On the data front• Endogenous growth testing• leave out control totalsRely on vital stats on local populationSpecify a business development model based on net businessestablishment by sector• More parsimonious, but still robust models?• Alternatively, apply machine learning to fix data


CTPP jobsD&B 2001Scaled toABAGD&BunscaledABAGJobsCTPP jobs 1 0.896402 0.968573 1D&B 2001 Scaled toABAG 0.896402 1 0.958514 0.896456D&B unscaled 0.968573 0.958514 1 0.968587ABAGJobs 1 0.896456 0.968587 1* Mean Absolute Percentage Error is .12

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