The ability to predict with reasonable accuracy future levels of passengers and their associated revenue is a key requirement of policy makers facing decisions on service, fare and revenue support levels. This paper describes work undertaken at WYPTE to develop a predictive model sensitive to external changes in the economy as well as to the key internal factors of fare and service level. So far the model embraces the 54% of passengers paying a fare on the PTE's directly-operated services (the predominantly urban routes in Leeds, Bradford, Huddersfield and Halifax). Passenger categories not yet covered are those paying a fare on NBC services (27%), non-farebox passengers (notably travelcard users) (15%), and those using rail (3%). The model requirements of aggregate demand forecasting, coupled with the availability of four-weekly time series data for revenue, bus-miles etc, make the technique of multiple regression analysis an obvious choice of method. The paper highlights the importance of using accurate data, a requirement perhaps more easily met by in-house research, and of determining the appropriate form of model, where data availability, statistical tests, economic theory and ease of prediction govern the choice of variables and the form in which they are used. Since the method employed is well established, the main interest probably centres on the results which, expressed as fare and service elasticities, are broadly consistent with other studies. However, fresh ground may have been covered in the analysis of exogenous demand determinants. In addition to real earnings (which is of minor significance) and a time trend (included to embrace any factor not specifically analysed) the model identified unemployment as a major influence on patronage. Both the absolute level and the change in level are considered to affect demand, the former perhaps as a reflection of the level of employment and of income (as distinct from earnings), while the change in unemployment has been included specifically to provide a good local proxy for short-time working, which is regarded as a short-term maladjustment of labour supply to demand. Reconciliation of the individual findings with generalised cost and various available statistics is discussed. After further consideration of fares, where evidence is sought for a shifting elasticity, money illusion and non-reversible effects, the final section of the paper considers applications of the model. Primarily employed to forecast short and medium-term aggregate demand and receipts levels, the limitations of overall fare and service elasticities are stressed. The model can also explain the changes in the pte's past patronage levels, distinguishing in particular between external and internal factors. Finally implications for optimal fare and service levels at given revenue support levels are discussed. (Author/TRRL)

  • Availability:
  • Supplemental Notes:
    • Public Transport. Proceedings of Seminar M held at the PTRC 10th Summer Annual Meeting, University of Warwick, England.
  • Corporate Authors:

    PTRC Education and Research Services Limited

    110 Strand
    London WC2,   England 
  • Authors:
    • FISHER, R M
    • Grimshaw, F R
    • Tebb, RGP
  • Conference:
  • Publication Date: 1982

Media Info

  • Features: References; Tables;
  • Pagination: p. 55-66

Subject/Index Terms

Filing Info

  • Accession Number: 00381676
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • ISBN: 0-86050-111-6
  • Files: ITRD, TRIS
  • Created Date: Mar 30 1984 12:00AM