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Accuracy and bias of experts’ adjusted forecasts

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  • Lin, Vera Shanshan
  • Goodwin, Paul
  • Song, Haiyan

Abstract

This study investigates whether experts’ group-based judgmental adjustments to econometric forecasts of tourism demand improve the accuracy of the forecasts and whether the adjusted forecasts are unbiased. The Delphi method was used to aggregate experts’ judgmental adjustments and a range of error measures and statistical tests were employed to evaluate forecast accuracy. Regression analysis was used to investigate whether the statistical and judgmentally-adjusted forecasts were unbiased. The hypothesis tests suggested that, on average, the adjustments of the Delphi panel improved forecast accuracy though the group-adjusted forecasts were found to be biased for some of the individual markets. In-depth interviews with the Delphi panellists provided further insights into the biases that were associated with the Delphi surveys.

Suggested Citation

  • Lin, Vera Shanshan & Goodwin, Paul & Song, Haiyan, 2014. "Accuracy and bias of experts’ adjusted forecasts," Annals of Tourism Research, Elsevier, vol. 48(C), pages 156-174.
  • Handle: RePEc:eee:anture:v:48:y:2014:i:c:p:156-174
    DOI: 10.1016/j.annals.2014.06.005
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    References listed on IDEAS

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    Cited by:

    1. Toppinen, Anne & Röhr, Axel & Pätäri, Satu & Lähtinen, Katja & Toivonen, Ritva, 2018. "The future of wooden multistory construction in the forest bioeconomy – A Delphi study from Finland and Sweden," Journal of Forest Economics, Elsevier, vol. 31(C), pages 3-10.
    2. Arvan, Meysam & Fahimnia, Behnam & Reisi, Mohsen & Siemsen, Enno, 2019. "Integrating human judgement into quantitative forecasting methods: A review," Omega, Elsevier, vol. 86(C), pages 237-252.
    3. Winkler, Jens & Moser, Roger, 2016. "Biases in future-oriented Delphi studies: A cognitive perspective," Technological Forecasting and Social Change, Elsevier, vol. 105(C), pages 63-76.

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