By using traffic analysis zones (TAZs), centroids, and a road network as the inputs, traffic demand modeling aggregates trips from the locations of individual tripmakers to TAZ centroids and estimates trips generated between TAZs on the network. Like spatial analysis, traffic demand modeling is subject to the modifiable areal unit problem (MAUP). In this paper we report the findings of a simulation study, which uses eleven zoning structures and two levels of network detail to assess the effects of TAZs, centroids, and network detail on statewide traffic demand modeling in Idaho. First, trips generated between smaller TAZs have shorter trip lengths, higher proportions of interzonal trips, more accurate estimated volume-to-ground-count ratios, and lower percentage root mean square errors (ERMS) between estimated volumes and ground counts. Second, the effect of centroid locations is mixed and generally slight with small TAZs. Third, the level of network detail impacts ERMS values in two ways: larger TAZs produce lower ERMS values than smaller TAZs on the less detailed network, and the detailed network outperforms the less detailed network, regardless of the size of TAZs.
Get full access to this article
View all access options for this article.
References
1.
AmrheinC G, 1995, “Searching for the elusive aggregation effect: evidence from statistical simulations”Environment and Planning A27105–119
2.
Barton-Aschman Associates Inc, Cambridge Systematics Inc, 1997Model Validation and Reasonableness Checking Manual prepared for Federal Highway Administration, US Department of Transportation, 400 Seventh Street, SW, Washington, DC 20590
3.
BattyMSikdarP K, 1982a, “Spatial aggregation in gravity models. 1. An information theoretic framework”Environment and Planning A14377–405
4.
BattyMSikdarP K, 1982b, “Spatial aggregation in gravity models. 2. One-dimensional population density models”Environment and Planning A14524–553
5.
BattyMSikdarP K, 1982c, “Spatial aggregation in gravity models. 3. Two-dimensional trip distribution and location models”Environment and Planning A14629–658
6.
BattyMSikdarP K, 1982d, “Spatial aggregation in gravity models. 4. Generalisations and large-scale applications”Environment and Planning A14795–822
7.
ClarkW A VAveryK L, 1976, “The effect of data aggregation in statistical analysis”Geographical Analysis8428–437
8.
CrevoC C, 1991, “Impacts of zonal reconfigurations on travel demand forecasts”, in Transportation Research Record number 1305, pp 72–80, Transportation Research Board, National Research Council, Washington, DC
9.
CrevoC CNiedowskiR SScottD J, 1995, “Design and conduct of a statewide household travel survey in Vermont”, in Transportation Research Record number 1477, pp 26–30, Transportation Research Board, National Research Council, Washington, DC
10.
DingC, 1994, “Impact analysis of spatial data aggregation on transportation forecasted demand: a GIS approach”, in URISA Proceedings URISA, 1460 Renaissance Drive, Park Ridge, IL 60068, pp 362–375
11.
DingC, 1998, “The GIS-based human-interactive TAZ design algorithm: examining the impacts of data aggregation on transportation-planning analysis”Environment and Planning B: Planning and Design25601–616
12.
EdwardsJ D (Ed.), 1999Transportation Planning Handbook2nd edition, Institute of Transportation Engineers, 1099 14th Street, NW, Washington, DC 20005
13.
FHWA, 1990, “Calibration and adjustment of system planning models”, US Department of Transportation, 400 Seventh Street, SW, Washington, DC 20590, http://www.bts.gov/NTL/DOCS/377CAS.html
14.
FHWA, 1999, “Guidebook on statewide travel forecasting”, US Department of Transportation, 400 Seventh Street, SW, Washington, DC 20590
15.
FotheringhamA SWongD W S, 1991, “The modifiable areal unit problem in multivariate statistical analysis”Environment and Planning A231025–1044
16.
FrancisR LLoweT JRushtonGRaycoM B, 1999, “A synthesis of aggregation methods for multifacility location problem: strategies for containing error”Geographical Analysis3167–87
17.
GoodchildM F, 1979, “The aggregation problem in location–allocation”Geographica Analysis11240–255
18.
HorowitzA JFarmerD D, 1999, “Statewide travel forecasting practice: a critical review”, in Transportation Research Record number 1685, pp 13–20, Transportation Research Board
19.
MartinW AMcGuckinN A, 1993, “Travel estimation techniques for urban planning”, prepared for the National Cooperative Highway Research Program, Transportation Research Board, The National Academies, 2101 Constitution Avenue, NW, Washington, DC 20418
20.
MillerH J, 1999, “Potential contributions of spatial analysis to geographic information systems for transportation”Geographical Analysis31373–399
21.
O'NeillW A, 1991, “Developing optimal transportation analysis zones using GIS”ITE Journal61 (December) 33–36
22.
OpenshawS, 1977, “Optimal zoning systems for spatial interaction models”Environment and Planning A9169–184
23.
OpenshawSTaylorP J, 1979, “A million or so correlation coefficients: three experiments on the modifiable areal unit problem”, in Statistical Applications in the Spatial Sciences Ed. WrigleyN (Pion, London) pp 127–144
24.
OrdJ KCliffA D, 1976, “The analysis of commuting patterns”Environment and Planning A8941–946
25.
OttL R, 1993An Introduction to Statistical Methods and Data Analysis4th edition (Duxbury Press, Boston, MA)
RobinsonW S, 1950, “Ecological correlation and the behavior of individuals”American Sociological Review15351–357
28.
SosslauA B, 1973, “Traffic assignment”, FHWA, US Department of Transportation, 400 Seventh Street, SW, Washington, DC 20590
29.
VirkudUKeyesC S, 1995, “Design and implementation of a statewide roadside origin destination survey in Vermont”Transportation Research Record147715–25, Transportation Research Board, National Research Council, Washington, DC
30.
WilsonE MWangJ, 1995Statewide Transportation Planning—An Interactive Modeling ProcessWyoming Department of Transportation, 5300 Bishop Boulevard, Cheyenne, WY 82009
31.
WongDAmrheinC, 1996, “Research on the MAUP: old wine in a new bottle or real breakthrough”Geographical Systems373–16
32.
YouJNedovic-BudicZKimT J, 1997a, “A GIS-based traffic analysis zone design: technique”Transportation Planning and Technology2145–68
33.
YouJNedovic-BudicZKimT J, 1997b, “A GIS-based traffic analysis zone design: implementation and evaluation”Transportation Planning and Technology2169–91
