ARE PERSONS OR HOUSEHOLDS THE BASIC UNIT OF TRAVEL DEMAND SIMULATION? THE CONCEPT OF A HYBRID MODEL

Since the mid-seventies, different types of individual oriented models have been in use in the Federal Republic of Germany. The main objection to simulation techniques was that although the process of trafficgeneration in the model algorithm was attributed to "individuals" (defined sociodemographically and grouped according to more or less homogeneous behaviour) options were defined for the travel behaviour of the "individuals" which (as could easily be demonstrated) simply did not exist or existed only to a very limited extent. Another frequent objection was that these models are only of very limited value for forecasting because they require complex data input and they have a pronounced status-quo nature. Finally, there is some transport behaviour to be modelled is to be sought in the individual or rather in the household. The stage of development of an individual-oriented behavioural model presented here tries to answer the above questions. It is shown that (in agreement with the nature of a hybrid model) one can neither do without the household nor without the individual. This is due to the fact that some important options are already defined by the household, although those alternative modes of action which remain open to the individual are also to be included in the considerations. Since this model process also subdivides the "individuals" who have been defined into groups of individuals who either do or do not have options open to them, the number of alternatives can be reduced to a realistic level step by step. It is shown that the limited value of the model for forecasting purposes has been incorrectly questioned in regard to the sociodemographic requirements of the data input. Furthermore, the possibilities offered by an alternative approach, i.e. the estimation of behavioural changes on hand of interactive measurements, are shown using available interactive measurement methods as a background. In the much broader question of the transferability over time of the transport behaviour, the mathematical results of a transfer of the measured status-quo behaviour and its regularity in the future are presented. (TRRL) abstract of the seminar see IRRD 273131.

  • Availability:
  • Supplemental Notes:
    • This paper was presented at Seminar N, Developing Countries, held at the PTRC Annual Summer Meeting, University of Sussex, England, 4-7 July, 1983.
  • Corporate Authors:

    PTRC Education and Research Services Limited

    110 Strand
    London WC2,   England 
  • Authors:
    • Zumkeller, D
  • Conference:
  • Publication Date: 1983

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 269-284

Subject/Index Terms

Filing Info

  • Accession Number: 00382864
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • ISBN: 0-86050-112-4
  • Report/Paper Numbers: Volume P240
  • Files: ITRD, TRIS
  • Created Date: May 30 1984 12:00AM