IDEAS home Printed from
   My bibliography  Save this article

The impact of ignoring intrazonal trips in assignment models: a stochastic approach


  • Ouassim Manout

    () (University of Lyon

  • Patrick Bonnel

    () (University of Lyon)


In transportation modeling, intrazonal trips are frequently omitted during trip assignment. These trips are not assigned to the network because their origin and destination are in the same zone. However, in reality, intrazonal trips use the network and take up some of its capacity. This omission is due to the spatial aggregation problem. Omitting these short trips from assignment models affects the level of service of the network and biases the estimation of main assignment outcomes. The issue of intrazonal trips omission has received limited attention in transportation research. In this paper, we address the problem of ignoring intrazonal trips in traffic assignment models by applying a stochastic approach in order to characterize the statistical impact of their omission. Our results show that the omission of intrazonal trips has a significant impact on main assignment results. Network speeds, volumes and congestion levels vary significantly with the omission of intrazonal trips. The extent of this impact depends on the road’s category in the network hierarchy. As regards level of service, local streets are more sensitive to the omission of intrazonal trips than the primary network. These findings reveal the existence of a bias due to the omission of intrazonal trips in assignment models and raise doubts about the accuracy and reliability of assignment results from standard four step transport models especially when the spatial zoning is coarse.

Suggested Citation

  • Ouassim Manout & Patrick Bonnel, 2019. "The impact of ignoring intrazonal trips in assignment models: a stochastic approach," Transportation, Springer, vol. 46(6), pages 2397-2417, December.
  • Handle: RePEc:kap:transp:v:46:y:2019:i:6:d:10.1007_s11116-018-9951-y
    DOI: 10.1007/s11116-018-9951-y

    Download full text from publisher

    File URL:
    File Function: Abstract
    Download Restriction: Access to full text is restricted to subscribers.

    As the access to this document is restricted, you may want to search for a different version of it.

    References listed on IDEAS

    1. Skamris, Mette K. & Flyvbjerg, Bent, 1997. "Inaccuracy of traffic forecasts and cost estimates on large transport projects," Transport Policy, Elsevier, vol. 4(3), pages 141-146, July.
    2. A Rodriguez-Bachiller, 1983. "Errors in the Measurement of Spatial Distances between Discrete Regions," Environment and Planning A, , vol. 15(6), pages 781-799, June.
    3. Kang-Tsung Chang & Zaher Khatib & Yanmei Ou, 2002. "Effects of Zoning Structure and Network Detail on Traffic Demand Modeling," Environment and Planning B, , vol. 29(1), pages 37-52, February.
    4. S Openshaw, 1977. "Optimal Zoning Systems for Spatial Interaction Models," Environment and Planning A, , vol. 9(2), pages 169-184, February.
    5. (Sean) Qian, Zhen & Zhang, H.M., 2012. "On centroid connectors in static traffic assignment: Their effects on flow patterns and how to optimize their selections," Transportation Research Part B: Methodological, Elsevier, vol. 46(10), pages 1489-1503.
    6. Daganzo, Carlos F., 1980. "Network representation, continuum approximations and a solution to the spatial aggregation problem of traffic assignment," Transportation Research Part B: Methodological, Elsevier, vol. 14(3), pages 229-239, September.
    7. S Openshaw, 1978. "An Empirical Study of Some Zone-Design Criteria," Environment and Planning A, , vol. 10(7), pages 781-794, July.
    8. Daganzo, Carlos F., 1980. "An equilibrium algorithm for the spatial aggregation problem of traffic assignment," Transportation Research Part B: Methodological, Elsevier, vol. 14(3), pages 221-228, September.
    9. C Ding, 1998. "The GIS-Based Human-Interactive TAZ Design Algorithm: Examining the Impacts of Data Aggregation on Transportation-Planning Analysis," Environment and Planning B, , vol. 25(4), pages 601-616, August.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Manout, Ouassim & Bonnel, Patrick & Bouzouina, Louafi, 2018. "Transit accessibility: A new definition of transit connectors," Transportation Research Part A: Policy and Practice, Elsevier, vol. 113(C), pages 88-100.
    2. Richard Connors & David Watling, 2015. "Assessing the Demand Vulnerability of Equilibrium Traffic Networks via Network Aggregation," Networks and Spatial Economics, Springer, vol. 15(2), pages 367-395, June.
    3. Raadsen, Mark P.H. & Bliemer, Michiel C.J. & Bell, Michael G.H., 2020. "Aggregation, disaggregation and decomposition methods in traffic assignment: historical perspectives and new trends," Transportation Research Part B: Methodological, Elsevier, vol. 139(C), pages 199-223.
    4. Luca Quadrifoglio & Randolph W. Hall & Maged M. Dessouky, 2006. "Performance and Design of Mobility Allowance Shuttle Transit Services: Bounds on the Maximum Longitudinal Velocity," Transportation Science, INFORMS, vol. 40(3), pages 351-363, August.
    5. Brinkman, Anthony P., 2003. "The Ethical Challenges and Professional Responses of Travel Demand Forecasters," Institute of Transportation Studies, Research Reports, Working Papers, Proceedings qt9c3330tt, Institute of Transportation Studies, UC Berkeley.
    6. Ghadiri, Mehdi & Rassafi, Amir Abbas & Mirbaha, Babak, 2019. "The effects of traffic zoning with regular geometric shapes on the precision of trip production models," Journal of Transport Geography, Elsevier, vol. 78(C), pages 150-159.
    7. Cabrera Delgado, Jorge & Bonnel, Patrick, 2016. "Level of aggregation of zoning and temporal transferability of the gravity distribution model: The case of Lyon," Journal of Transport Geography, Elsevier, vol. 51(C), pages 17-26.
    8. Brinkman, P. Anthony, 2003. "The Ethical Challenges and Professional Responses of Travel Demand Forecasters," University of California Transportation Center, Working Papers qt7vb2d17h, University of California Transportation Center.
    9. Cathy Macharis & Peter Nijkamp, 2013. "Multi-actor and multi-criteria analysis in evaluating mega-projects," Chapters, in: Hugo Priemus & Bert van Wee (ed.), International Handbook on Mega-Projects, chapter 11, pages 242-266, Edward Elgar Publishing.
    10. Feng Guo & Lisa Aultman-Hall, 2014. "A zone design methodology for national freight origin-destination data and transportation modeling," Transportation Planning and Technology, Taylor & Francis Journals, vol. 37(8), pages 738-756, December.
    11. Herrera Gómez, Marcos & Mur Lacambra, Jesús & Ruiz Marín, Manuel, 2012. "Selecting the Most Adequate Spatial Weighting Matrix:A Study on Criteria," MPRA Paper 73700, University Library of Munich, Germany.
    12. Peter Stopher & Stephen Greaves, 2007. "Guidelines for samplers: measuring a change in behaviour from before and after surveys," Transportation, Springer, vol. 34(1), pages 1-16, January.
    13. Michal Bernard Pietrzak, 2014. "Redefining The Modifiable Areal Unit Problem Within Spatial Econometrics, The Case Of The Aggregation Problem," Equilibrium. Quarterly Journal of Economics and Economic Policy, Institute of Economic Research, vol. 9(3), pages 131-151, September.
    14. Michal Bernard Pietrzak, 2014. "The Modifiable Areal Unit Problem – Analysis Of Correlation And Regression," Equilibrium. Quarterly Journal of Economics and Economic Policy, Institute of Economic Research, vol. 9(4), pages 113-131, December.
    15. Frank Corvers & Maud Hensen & Dion Bongaerts, 2009. "Delimitation and Coherence of Functional and Administrative Regions," Regional Studies, Taylor & Francis Journals, vol. 43(1), pages 19-31.
    16. Verweij, Stefan & van Meerkerk, Ingmar & Korthagen, Iris A., 2015. "Reasons for contract changes in implementing Dutch transportation infrastructure projects: An empirical exploration," Transport Policy, Elsevier, vol. 37(C), pages 195-202.
    17. Chong, Uven & Hopkins, Omar, 2016. "An international experience on the evolution of road costs during the project life cycle," Transport Policy, Elsevier, vol. 48(C), pages 60-66.
    18. Maud M. Hensen & M. Robert De Vries & Frank Cörvers, 2009. "The role of geographic mobility in reducing education‐job mismatches in the Netherlands," Papers in Regional Science, Wiley Blackwell, vol. 88(3), pages 667-682, August.
    19. Patricia Mokhtarian & Ilan Salomon & Sangho Choo, 2005. "Measuring the Measurable: Why can’t we Agree on the Number of Telecommuters in the U.S.?," Quality & Quantity: International Journal of Methodology, Springer, vol. 39(4), pages 423-452, August.
    20. Ouassim Manout & Patrick Bonnel & François Pacull, 2020. "The impact of centroid connectors on transit assignment outcomes," Public Transport, Springer, vol. 12(3), pages 611-629, October.


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:kap:transp:v:46:y:2019:i:6:d:10.1007_s11116-018-9951-y. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Sonal Shukla) or (Springer Nature Abstracting and Indexing). General contact details of provider: .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.