手法を比較

	ロバスト イベントツリー解析	ロバスト故障の木解析
分野	実験計画法	実験計画法
系統	Process / pipeline	Process / pipeline
提唱年	1960s (ETA); robust extensions ~1990s–2000s	1980s–2000s (robustness extensions to classical FTA ca. 1961)
提唱者	H.E. Lambert / Nuclear industry (ETA); robust extensions developed through aerospace and nuclear risk research	Extended from classical FTA (Watson, 1961; Bell Labs / U.S. Air Force); robustness extensions developed through reliability engineering and uncertainty quantification research from the 1980s onward
種類	Probabilistic risk assessment with uncertainty propagation	Quantitative reliability and safety analysis with uncertainty propagation
原典	Bedford, T., & Cooke, R. M. (2001). Probabilistic Risk Analysis: Foundations and Methods. Cambridge University Press. ISBN: 9780521773201	Vesely, W. E., Goldberg, F. F., Roberts, N. H., & Haasl, D. F. (1981). Fault Tree Handbook. U.S. Nuclear Regulatory Commission, NUREG-0492.
別名	Robust ETA, uncertainty-aware event tree analysis, ETA with uncertainty quantification, robust probabilistic event tree	Robust FTA, Uncertainty-aware FTA, FTA with interval analysis, Imprecise probability FTA
関連	6	6
概要	Robust Event Tree Analysis (Robust ETA) extends classical event tree analysis by explicitly accounting for uncertainty in the probability estimates assigned to each branch. Rather than treating branch probabilities as precise point values, the robust approach represents them as intervals, probability distributions, or imprecise probabilities, then propagates that uncertainty through the tree to produce outcome frequency ranges instead of single numbers. This gives decision-makers a clearer picture of the confidence in risk estimates under realistic conditions of incomplete or conflicting information.	Robust Fault Tree Analysis (Robust FTA) extends classical fault tree analysis by explicitly representing and propagating uncertainty in component failure probabilities. Rather than assigning single point estimates to basic events, it uses probability distributions, interval bounds, or imprecise probabilities, then propagates these through the logical tree structure to obtain bounds or distributions on the top-event failure probability. This makes risk conclusions defensible under incomplete or variable data.