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Understanding the role of the forecast-maker in overestimation forecasts of policy impacts: The case of Travel Demand Management policies

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  • Tal, Gil
  • Cohen-Blankshtain, Galit

Abstract

Forecasting the impacts of a proposed policy is an important component of the transportation planning and decision making process. Although scientific tools are often used in transportation forecasts, biases and, more specifically, overestimations of the expected impact are often observed. This study explores the correlations between forecast-maker's characteristics and forecast bias creation and reduction. The study examines two transport-related policies aiming at the reduction of car use: telecommuting and carsharing. Both are Travel Demand Management (TDM) policies, which attract much attention from transport experts. We tested the extent to which the forecast-maker's beliefs about the policy at stake affected the forecast bias. We found that attitudes and beliefs associates not only with overestimation bias but also with its reduction over time. We also tested the extent to which the forecast-maker's affiliation, the performing institute and the publication type were correlated with the biases of the forecast and with the forecaster attitudes and beliefs. These characteristics are intuitively used by the forecast user as tools to assess the 'objectivity' of the forecast, but our analysis found no association between these characteristics and the forecast bias.

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  • Tal, Gil & Cohen-Blankshtain, Galit, 2011. "Understanding the role of the forecast-maker in overestimation forecasts of policy impacts: The case of Travel Demand Management policies," Transportation Research Part A: Policy and Practice, Elsevier, vol. 45(5), pages 389-400, June.
    • Handle: RePEc:eee:transa:v:45:y:2011:i:5:p:389-400
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    1. repec:cdl:itsdav:qt1qk959v1 is not listed on IDEAS
    2. Shaheen, Susan & Sperling, Daniel & Wagner, Conrad, 1998. "Carsharing in Europe and North American: Past, Present, and Future," University of California Transportation Center, Working Papers qt4gx4m05b, University of California Transportation Center.
    3. Steininger, Karl & Vogl, Caroline & Zettl, Ralph, 1996. "Car-sharing organizations : The size of the market segment and revealed change in mobility behavior," Transport Policy, Elsevier, vol. 3(4), pages 177-185, October.
    4. Martin, Elliot & Shaheen, Susan Alison & Lidicker, Jeffrey, 2010. "Carsharing’S Impact On Household Vehicle Holdings: Results From A North American Shared-Use Vehicle Survey," Institute of Transportation Studies, Research Reports, Working Papers, Proceedings qt0850h6r5, Institute of Transportation Studies, UC Berkeley.
    5. Baghestani, Hamid, 2008. "Federal Reserve versus private information: Who is the best unemployment rate predictor," Journal of Policy Modeling, Elsevier, vol. 30(1), pages 101-110.
    6. repec:cdl:itsdav:qt0850h6r5 is not listed on IDEAS
    7. Sangho Choo & Patricia Mokhtarian & Ilan Salomon, 2005. "Does telecommuting reduce vehicle-miles traveled? An aggregate time series analysis for the U.S," Transportation, Springer, vol. 32(1), pages 37-64, January.
    8. Mackie, Peter & Preston, John, 1998. "Twenty-one sources of error and bias in transport project appraisal," Transport Policy, Elsevier, vol. 5(1), pages 1-7, January.
    9. Daniel Kahneman & Amos Tversky, 2013. "Prospect Theory: An Analysis of Decision Under Risk," World Scientific Book Chapters, in: Leonard C MacLean & William T Ziemba (ed.), HANDBOOK OF THE FUNDAMENTALS OF FINANCIAL DECISION MAKING Part I, chapter 6, pages 99-127, World Scientific Publishing Co. Pte. Ltd..
    10. Meyer, Michael D., 1999. "Demand management as an element of transportation policy: using carrots and sticks to influence travel behavior," Transportation Research Part A: Policy and Practice, Elsevier, vol. 33(7-8), pages 575-599.
    11. Mackett, Roger L. & Edwards, Marion, 1998. "The impact of new urban public transport systems: will the expectations be met?," Transportation Research Part A: Policy and Practice, Elsevier, vol. 32(4), pages 231-245, May.
    12. Marshall, Stephen & Banister, David, 2000. "Travel reduction strategies: intentions and outcomes," Transportation Research Part A: Policy and Practice, Elsevier, vol. 34(5), pages 321-338, June.
    13. Brinkman, P. Anthony, 2003. "The Ethical Challenges and Professional Responses of Travel Demand Forecasters," University of California Transportation Center, Working Papers qt6dv0z95g, University of California Transportation Center.
    14. Jenkins-Smith, Hank C. & Sabatier, Paul A., 1994. "Evaluating the Advocacy Coalition Framework," Journal of Public Policy, Cambridge University Press, vol. 14(2), pages 175-203, April.
    15. Richard Boylan, 2008. "Political distortions in state forecasts," Public Choice, Springer, vol. 136(3), pages 411-427, September.
    16. 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.
    17. David Laster & Paul Bennett & In Sun Geoum, 1999. "Rational Bias in Macroeconomic Forecasts," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 114(1), pages 293-318.
    18. 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.
    19. Patricia L. Mokhtarian, 1998. "A Synthetic Approach to Estimating the Impacts of Telecommuting on Travel," Urban Studies, Urban Studies Journal Limited, vol. 35(2), pages 215-241, February.
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