مقایسهٔ روش‌ها

	Probable Maximum Loss Estimation	HAZUS Loss Estimation
حوزه	Disaster Studies	Disaster Studies
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	2005	2006
پدیدآور	Patricia Grossi & Howard Kunreuther; Kirsten Mitchell-Wallace et al.	Federal Emergency Management Agency; Charles Kircher, Robert Whitman & William Holmes
نوع	Tail (return-period) loss metric read from a loss exceedance distribution	Standardized GIS-based multi-hazard loss-estimation pipeline
منبع بنیادین	Grossi, P., & Kunreuther, H. (Eds.) (2005). Catastrophe Modeling: A New Approach to Managing Risk. Springer. ISBN: 9780387241050	Kircher, C. A., Whitman, R. V., & Holmes, W. T. (2006). HAZUS Earthquake Loss Estimation Methods. Natural Hazards Review, 7(2), 45-59.
نام‌های دیگر	Probable Maximum Loss (PML), Return-Period Loss, Tail Loss Estimation, Catastrophe Value-at-Risk	Hazus-MH Loss Estimation, FEMA Hazus Methodology, Standardized Regional Loss Estimation, Hazus Earthquake Model
مرتبط	4	4
خلاصه	Probable maximum loss (PML) estimation reads a tail loss, the loss associated with a chosen rare return period or exceedance probability, from the loss exceedance curve produced by a probabilistic risk or catastrophe model. Where average annual loss summarizes the mean of the loss distribution, PML characterizes its extreme: a 1-in-250-year PML is the loss level exceeded with one percent probability in a year (a 0.4 percent probability for 1-in-250). Patricia Grossi and Howard Kunreuther's 2005 volume sets out PML and the exceedance-probability curve as core catastrophe-model outputs, and Kirsten Mitchell-Wallace and colleagues' 2017 practitioner's guide details how the industry computes and uses PML, including the crucial distinction between occurrence and aggregate exceedance. PML is the metric that drives solvency capital, reinsurance purchase, risk appetite, and regulatory stress tests, because catastrophe risk is about surviving the rare bad year, not the average one. It is a percentile (value-at-risk) of the loss distribution and therefore inherits both the power and the fragility of tail estimation. Defining it precisely, return period, occurrence versus aggregate, and uncertainty, is essential to using it responsibly.	HAZUS loss estimation is FEMA's standardized, GIS-based methodology for estimating the physical, social, and economic consequences of earthquakes, floods, hurricanes, and tsunamis across a region. It chains together four conceptual modules, potential hazard, inventory of the built environment, direct physical damage, and induced and economic losses, so that a consistent national framework can produce comparable loss estimates anywhere in the United States. Charles Kircher, Robert Whitman, and William Holmes's 2006 paper documents the earthquake methodology, including its use of capacity-spectrum demand estimation and lognormal fragility curves, and FEMA's technical manuals specify every default inventory, fragility, and loss parameter. The system is distinguished less by methodological novelty than by standardization: it packages decades of earthquake and flood loss science into reproducible software with vetted defaults. Planners, emergency managers, and policymakers use it for scenario planning, mitigation prioritization, and disaster response. Because its defaults are transparent and documented, HAZUS is both a working tool and a reference implementation of regional loss estimation.