Reflections on the application of the Delphi method: lessons from a case in public transport research

ABSTRACT The paper outlines the author’s experience employing the Delphi method, using as an example a particular application of the Delphi in the field of public transport research. Attention is given to aspects such as the choice of method, selection of experts, design of questionnaires, interaction between survey coordinator and participants, and also the analysis of experts’ responses. Some of the challenges encountered during the survey, the way they were dealt with, and risk mitigation strategies used by the Delphi coordinator are highlighted too. The primary objective of this paper is to offer insights that can support other researchers or practitioners preparing to apply the Delphi methodology. Furthermore, the article contributes to the methodological debate by reflecting on the introduction of novel practices that can help overcome some typical pitfalls of the Delphi: a dedicated blog supporting the survey, safety-net questions, and a constant-sum type question.

[1]  Glenn A. Bowen.  Grounded Theory and Sensitizing Concepts , 2006 .

[2]  J. Anable,et al.  Scientific research about climate change mitigation in transport: a critical review , 2011 .

[3]  Iain Docherty,et al.  STATE INTERVENTION IN CONTEMPORARY TRANSPORT , 2004 .

[4]  J. Crisp,et al.  The Delphi method? , 1997, Nursing research.

[5]  E. Ostrom.  Beyond Markets and States: Polycentric Governance of Complex Economic Systems , 2010, American Economic Review.

[6]  J. Dijk.  Delphi questionnaires versus individual and group interviews , 1990 .

[7]  Wayne K. Talley,et al.  Stability and agreement criteria for the termination of Delphi studies , 1979 .

[8]  David H. Gustafson,et al.  Group Techniques for Program Planning: A Guide to Nominal Group and Delphi Processes , 1976 .

[9]  E. Chadwick,et al.  Results of Different Principles of Legislation and Administration in Europe; of Competition for the Field, as Compared with Competition Within the Field, of Service , 1859 .

[10]  Andreas Vigren,et al.  Cost Efficiency in Swedish Public Transport , 2016 .

[11]  Dan Murray,et al.  Advancing the State of Policy Delphi Practice: A Systematic Review Evaluating Methodological Evolution, Innovation, and Opportunities , 2016 .

[12]  Roy C. Schmidt,et al.  MANAGING DELPHI SURVEYS USING NONPARAMETRIC STATISTICAL TECHNIQUES , 1997 .

[13]  James. Longhurst,et al.  Exploring a city's potential low carbon futures using Delphi methods: some preliminary findings , 2012 .

[14]  Kalle Lyytinen,et al.  Identifying Software Project Risks: An International Delphi Study , 2001, J. Manag. Inf. Syst..

[15]  Cary A. Brown.  The Opt‐in/Opt‐out Feature in a Multi‐Stage Delphi Method Study , 2007 .

[16]  D. Hensher,et al.  Delivering trusting partnerships for route bus services: A Melbourne case study , 2007 .

[17]  Murray Turoff,et al.  The design of a policy Delphi , 1970 .

[19]  J. Cowie.  Performance, profit and consumer sovereignty in the English deregulated bus market , 2014 .

[20]  Uma G. Gupta,et al.  Theory and applications of the Delphi technique: A bibliography (1975–1994) , 1996 .

[21]  G. Norman.  Likert scales, levels of measurement and the “laws” of statistics , 2010, Advances in health sciences education : theory and practice.

[22]  Rob C. de Loë,et al.  Exploring complex policy questions using the policy Delphi: A multi-round, interactive survey method , 1995 .

[23]  D. Murray,et al.  Perspectives of natural resource sector firms on collaborative approaches to governance for water , 2016 .

[24]  Simon Pemberton,et al.  Institutional governance, scale and transport policy – lessons from Tyne and Wear , 2000 .

[25]  Suzanne D. Pawlowski,et al.  The Delphi method as a research tool: an example, design considerations and applications , 2004, Inf. Manag..

[26]  George Wright,et al.  The Delphi technique as a forecasting tool: issues and analysis , 1999 .

[27]  Daniel Maxey,et al.  The Delphi technique: an untapped approach of participatory research , 2016 .

[28]  Hans de Bruijn,et al.  System and Actor Perspectives on Sociotechnical Systems , 2009, IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans.

[29]  W. Veeneman,et al.  Inventory and rating of performance indicators and organisational features in metropolitan public transport: A worldwide Delphi survey , 2018, Research in Transportation Economics.

[30]  Heiko A. von der Gracht,et al.  Consensus measurement in Delphi studies , 2012 .

[31]  Guy Paré,et al.  A systematic assessment of rigor in information systems ranking-type Delphi studies , 2013, Inf. Manag..

[32]  N. Dalkey,et al.  An Experimental Application of the Delphi Method to the Use of Experts , 1963 .

[33]  Martin Steinert,et al.  A dissensus based online Delphi approach: An explorative research tool , 2009 .

[34]  J. Landeta.  Current validity of the Delphi method in social sciences , 2006 .