手法を比較

	Policy Delphi	Delphi Method	政策シナリオ分析
分野	Public Policy	質的手法	シミュレーション
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1970	1963	1967–1990s
提唱者	Murray Turoff	Norman Dalkey & Olaf Helmer (RAND Corporation)	Kahn, H. & Wiener, A. J. (seminal); adapted for policy by RAND Corporation and OECD
種類	Structured, iterative expert-deliberation technique for policy	Structured iterative expert-elicitation process	Qualitative-quantitative hybrid scenario method
原典	Turoff, M. (1970). The design of a policy Delphi. Technological Forecasting and Social Change, 2(2), 149–171.	Dalkey, N. & Helmer, O. (1963). An Experimental Application of the Delphi Method to the Use of Experts. Management Science, 9(3), 458-467.	Swart, R., Raskin, P., Robinson, J. (2004). The problem of the future: sustainability science and scenario analysis. Global Environmental Change, 14(2), 137–146.
別名	Policy Delphi Technique, Turoff Policy Delphi, Decision Delphi	Delphi Yöntemi, Delphi technique, expert consensus method	PSA, Policy Scenarios, Policy Impact Scenario Analysis, Counterfactual Policy Analysis
関連	3	5	5
概要	The policy Delphi is a structured, iterative technique for eliciting and organising informed opinion on contested policy issues. Unlike the classical Delphi, which seeks consensus on a forecast, the policy Delphi is explicitly designed to generate the strongest possible opposing positions on a policy question and to expose the full range of options, supporting arguments and disagreements among a panel of knowledgeable stakeholders. Introduced by Murray Turoff in 1970, it conducts several anonymous rounds in which participants rate policy statements on dimensions such as desirability and feasibility, see aggregated feedback and the reasoning behind divergent views, and revise their positions — surfacing structured intelligence for decision-makers rather than a forced agreement.	The Delphi method is a structured, iterative survey technique developed by Norman Dalkey and Olaf Helmer at the RAND Corporation in 1963 for eliciting and converging expert opinion on complex topics where empirical data are unavailable or insufficient. It collects independent judgements from a geographically dispersed expert panel over multiple anonymous rounds, feeding aggregated results back to participants after each round so they can revise their views in light of the group's collective position.	Policy Scenario Analysis is a structured method for evaluating how different policy interventions perform across a range of plausible future states. By pairing specific policy levers with alternative scenarios, analysts can assess robustness, trade-offs, and unintended consequences of policy choices before implementation — making it a cornerstone of evidence-based policy design in fields from climate to public health.