The Argos Freight Modeling ProjectThe Argos Freight Modeling Project

Presentation to Presentation to

SCAG Modeling Task ForceSCAG Modeling Task Force

9/22/049/22/04Genevieve Giuliano

Peter Gordon

School of Policy, Planning and Development

University of Southern California

SPPD/ISI USC

The Argos Research ProjectThe Argos Research Project

Purpose: Develop an intra-metropolitan freight flow model using state of the art computer science techniquesResearch TeamResearch Team

Jose-Luis AmbiteJose-Luis Ambite Sr. Research Scientist, ISI, USCSr. Research Scientist, ISI, USC

Genevieve GiulianoGenevieve Giuliano Prof. Policy, Planning & Dev., USCProf. Policy, Planning & Dev., USC

Peter GordonPeter Gordon Prof. Pub Policy & Real Estate, USCProf. Pub Policy & Real Estate, USC

Qisheng PanQisheng Pan Assoc. Prof., Urban Planning, TSUAssoc. Prof., Urban Planning, TSU

LanLan WangLanLan Wang PhD student, SPPD, USCPhD student, SPPD, USC

Matthew WeathersMatthew Weathers PhD student, Computer Science, USCPhD student, Computer Science, USC

Paul PenderPaul Pender

Naqeeb AbbasiNaqeeb Abbasi

MPP student, SPPD, USCMPP student, SPPD, USC

MS student, Computer Science, USCMS student, Computer Science, USC

SPPD/ISI USC

Argos Project GoalsArgos Project Goals

1.1. Contribute to knowledge in both information Contribute to knowledge in both information science and social sciencescience and social science

2.2. Address a significant government problemAddress a significant government problem

3.3. Conduct interdisciplinary research that bridges Conduct interdisciplinary research that bridges information science and social scienceinformation science and social science

SPPD/ISI USC

The Intra-metropolitan Freight Flow The Intra-metropolitan Freight Flow Estimation ProblemEstimation Problem

ModelsModels– Goods movement as inter-regional trade problemGoods movement as inter-regional trade problem

Many good models of inter-regional freight flowsMany good models of inter-regional freight flowsHigh level of aggregation in geography, commoditiesHigh level of aggregation in geography, commoditiesDon’t translate easily to intra-metropolitan contextDon’t translate easily to intra-metropolitan context

– State-of-practice transportation planning modelsState-of-practice transportation planning modelsConventional urban models do not take freight directly into Conventional urban models do not take freight directly into accountaccountTraditional 4-step approach difficult to apply to freightTraditional 4-step approach difficult to apply to freight

– Differences in behavioral foundations of travel demandDifferences in behavioral foundations of travel demand– Variation in supply/demand across industry sectorsVariation in supply/demand across industry sectors– Changing industry dynamicsChanging industry dynamics

SPPD/ISI USC

Problems, con’tProblems, con’t

DataData– Extensive data requirementsExtensive data requirements

Flows by mode, commodity, value, origin & destinationFlows by mode, commodity, value, origin & destination– Lack of disaggregate dataLack of disaggregate data

US, state level data generally available; county and smaller unit US, state level data generally available; county and smaller unit limitedlimitedFine geography does not coincide with fine sector dataFine geography does not coincide with fine sector data

– Proprietary dataProprietary dataPrivate firms not required to release dataPrivate firms not required to release dataCustoms data processed by third partiesCustoms data processed by third partiesBlack box natureBlack box nature

– Survey dataSurvey dataInfrequent, costly to updateInfrequent, costly to update

SPPD/ISI USC

An Ideal Model Would…An Ideal Model Would…

……have solid behavioral foundationhave solid behavioral foundation

……be multi-modalbe multi-modal

……handle passenger and freight trip interactionshandle passenger and freight trip interactions

……minimize use of costly dataminimize use of costly data

……be easily updatedbe easily updated

……be transferablebe transferable

SPPD/ISI USC

Our ApproachOur Approach

Use accessible, reliable data sourcesUse accessible, reliable data sources– Available to publicAvailable to public– Regular updatesRegular updates– Transparent computationsTransparent computations– Produced by reliable sourcesProduced by reliable sources

Use economic supply/demand as model foundationUse economic supply/demand as model foundation

Use as much detail as possibleUse as much detail as possible– GeographyGeography– Economic sectorsEconomic sectors

SPPD/ISI USC

Basic Concepts of ModelBasic Concepts of Model

Freight supply/demand in two basic categoriesFreight supply/demand in two basic categories– Intra-regional – supply/demand within SCAG regionIntra-regional – supply/demand within SCAG region– Inter-regional – imports to, exports from, pass-through flowsInter-regional – imports to, exports from, pass-through flows

Intra-regional supply/demand Intra-regional supply/demand – Use IMPLAN I/O model for regionUse IMPLAN I/O model for region– Factor out imports/exportsFactor out imports/exports

Inter-regional supply/demandInter-regional supply/demand– Use import/export data sources (by mode)Use import/export data sources (by mode)– Identify import/export zones/nodesIdentify import/export zones/nodes

Use regional employment as control totalUse regional employment as control total

SPPD/ISI USC

Main Data SourcesMain Data Sources

ItemItem SourceSource CommentsComments

IMPLAN I/OIMPLAN I/O MIG, IncMIG, Inc Commercially available, updated Commercially available, updated annually, reliableannually, reliable

TAZ employment data by TAZ employment data by sectorsector

SCAG 2000 point SCAG 2000 point datadata

Emp totals < IMPLAN; adjust to Emp totals < IMPLAN; adjust to IMPLAN; updated infrequentlyIMPLAN; updated infrequently

Waterborne Waterborne imports/exportsimports/exports

WCUSWCUS Data are available online and Data are available online and updated annuallyupdated annually

Air imports/exportsAir imports/exports LAXLAX Flows by sector only for LAXFlows by sector only for LAX

Truck imports/exportsTruck imports/exports SCAG truck SCAG truck surveyssurveys

““one-shot” surveysone-shot” surveys

Rail imports/exportsRail imports/exports ITMSITMS Data not reliableData not reliable

I-O TABLE 2001

SCAG 2000 EMP

AGGREGATE SECTORS

ATTRACTIONS & PRODUCTIONS

($, JOBS, by TAZ)

AIRPORT DATAWCUS 2000 ITMS

LINKS TO IMPORT, EXPORT NODES

CONVERSION TO COMPATIBLE SECTOR,

$/TON VALUES

COMBINE INTER AND INTRA P& A

AGGREGATE TO REGIONAL TOTALS

GO TO TRANSPORTATION MODEL

INTRA-REGION IMPORTS/EXPORTS

SCAG SURVEY

FREIGHT FLOW MODEL: STEPS IN GENERATING

FREIGHT SUPPLY/DEMAND

CHECK

CHECK

SPPD/ISI USC

SOME DETAILS ON INTRA-METRO PORTION

SCAG 2000 EMP DATA

Employment by sector, TAZ

IMPLAN 2001 I/O

Regional transactions table

Apply sector IO coefficients to

employment data

Check/adjust to sector,

county totals

Generate supply, demand by TAZ, sector in jobs, $$

SPPD/ISI USC

SOME DETAILS ON FREIGHT TRANSPORTATION MODEL

N x N matrix of freight P’s, A’s in tons

Generate O-D matrix using gravity-type distribution model

Convert O-D flows to PCEs

SCAG region transportation network

with equilibrium passenger traffic

assignmentTraffic Assignment of freight PCEs

Equilibrium total traffic assignment

Factor out air, water,

rail

SPPD/ISI USC

Workflow for Freight EstimationWorkflow for Freight Estimation

SPPD/ISI USC

Recent WorkRecent Work

Update data sources to 2000, 2001Update data sources to 2000, 2001

Develop conversion table for sector codes (SIC, Develop conversion table for sector codes (SIC, NAICS, SITC, etc)NAICS, SITC, etc)

Seek better sources for ground imports/exportsSeek better sources for ground imports/exports

Seek better methods for $$/tons/jobs Seek better methods for $$/tons/jobs conversionsconversions

Develop logical internal checksDevelop logical internal checks

To learn more….http://www.isi.edu/~argosTo learn more….http://www.isi.edu/~argos