UCLA Institute of Transportation Studies

There are many methods for engaging experts in interactive groups to explore, clarify, and/or decide on various issues. In an investigation of possible future transportation and land use scenarios for California, we used techniques common to several methods and developed our own variation, a “hybrid policy Delphi,” for use with a panel of 18 experts. We applied it to explore the policies that would lead to these scenarios and the consequences that would result from them. Through our process, panel members discussed and reported on the future scenarios they considered most desirable and also the scenarios they considered most likely to materialize by 2050. Panelists reported that the scenario they considered the most desirable was also least likely to occur, and that the likely trajectory of California transportation and land use policies and practices will lead to the scenario panelists considered less desirable. This report reflects on the processes behind reaching these panel conclusions, a five-stage sequence of two meetings and three online questionnaires. Our mix of discussion and questionnaires traded the benefit of anonymity (common in Delphi methods) for the benefit of exploratory discussion (used in workshops, focus groups, and the nominal group technique). In addition, our use of surveys before and after meetings allowed tracking changes in panel opinion on a central question (scenario likelihood) and discussing survey results at meetings, at the cost of greater administrative effort. We discuss the results of this effort, reflect on how well our combination of methods worked, and conclude with a discussion of limitations and future directions.