手法を比較

	PESTEL Macro-Environmental Scanning	Weak Signal Analysis
分野	Futures Foresight Studies	Futures Foresight Studies
系統	Process / pipeline	Process / pipeline
提唱年	2003	1975
提唱者	Strategic-management macro-environmental analysis tradition; linked to foresight input stage by Joseph Voros	H. Igor Ansoff
種類	Structured macro-environmental audit feeding strategy	Early-warning pipeline for graduated response to faint strategic signals
原典	Voros, J. (2003). A generic foresight process framework. Foresight, 5(3), 10-21.	Ansoff, H. I. (1975). Managing strategic surprise by response to weak signals. California Management Review, 18(2), 21-33.
別名	PESTEL Analysis, PESTLE Analysis, Macro-Environmental Audit, PEST/PESTEL Scanning	Weak Signals, Ansoff Weak-Signal Analysis, Strategic Issue Early Warning, Graduated Response to Weak Signals
関連	4	4
概要	PESTEL macro-environmental scanning is a structured audit of the forces in an organization's wider operating environment, organized into six factor classes: Political, Economic, Social, Technological, Environmental, and Legal. Unlike open-ended horizon scanning, PESTEL is typically run as a deliberate audit that enumerates the specific drivers in each class, gathers evidence for them, and assesses their likely impact and direction so that the findings can feed directly into strategy formulation. It operationalizes the input stage of Joseph Voros's generic foresight process while retaining its roots in strategic management, where the explicit inclusion of a Legal dimension makes it well suited to regulated industries and compliance-sensitive decisions. As catalogued in the Millennium Project's Futures Research Methodology, macro-environmental scanning of this kind is a foundational discipline that grounds long-range strategy in a systematic reading of external forces rather than in the assumptions of the moment.	Weak signal analysis is H. Igor Ansoff's approach to managing strategic surprise by responding to faint, ambiguous early indicators of discontinuity long before they harden into unmistakable trends. Ansoff's 1975 argument was that organizations relying on strong, well-confirmed signals are condemned to react too late, because by the time a discontinuity is obvious the room to maneuver has collapsed; the alternative is to detect change while it is still a whisper and to graduate the response as the signal strengthens. The method rests on a ladder of knowledge states — from a vague sense that something is stirring to precise quantitative understanding — matched to a ladder of responses, from heightened awareness through increased strategic flexibility to direct action. As codified in the Millennium Project's Futures Research Methodology, weak signal analysis turns scanning from passive observation into an early-warning system that trades the certainty of late information for the maneuvering room of early, tentative response.