GRA · Disaster Risk Finance

Spatial financeWhere capital meets hazard, exposure and transition

Decision analysis under uncertainty for disaster risk finance

Decision analysis structures choices under uncertainty. In disaster risk finance it helps governments choose combinations of instruments, set triggers and weigh speed, cost and reliability, making their value judgements explicit.

02Application

What decision analysis under uncertainty does here.

Decision analysis under uncertainty provides structured methods for choosing among options when outcomes are uncertain and objectives conflict. It makes trade-offs and value judgements explicit. In disaster and crisis, sovereign and public finance, development finance and insurance and catastrophe, decision analysis helps choose actions that perform acceptably across interconnected risks and uncertain futures. It clarifies when to act now and when to keep options open. The canonical description is on the STEM Commons.

Choosing an instrument mix

Instrument combinations are compared on cost, speed and coverage across simulated disaster years, with the decision maker's priorities set explicitly.

Trigger threshold choice

The costs of false alarms and missed events are weighed to choose a trigger threshold for anticipatory finance.

Release rules for contingency funds

Decision rules for releasing funds are designed and tested against past events to check timeliness and fairness.

03Monitor

Uncertainty analysis.

The screen a team would use to follow this method: its measures, states and decisions. Names are examples and values are illustrative.

Uncertainty analysis

Disaster risk finance · Decision analysis · Run R-1927

Sensitivity rankedGRA · Disaster Risk Finance

Total-order sensitivity

Output distribution

Inputs

Contingent liability, 1-in-50Beta of GDP, statedexpert elicitation
Pre-arranged financeLognormal of 1-in-50 need, statedexpert elicitation
Time to disburseUniformdays, statedexpert elicitation
Basis riskUniform of events, statedexpert elicitation
Uncertainty analysis: the screen's structure, terms and states for Disaster risk finance.Example names and illustrative values; a design, not a record or a live system.
04Data

What the method consumes.

Datasets and records used by decision analysis under uncertainty on this platform, with the role each plays and the label its values carry. Sources are listed in the source register.

DataRoleLabel
Simulated loss yearsScenario inputsMODELLED
Instrument cost dataOptionsREPORTED
Past event recordsRule testingOBSERVED
05Loss model

Loss exceedance, average annual loss and probable maximum loss.

The loss a portfolio in the footprint can expect per year and at the 1 in 100 and 1 in 250 levels that insurers and lenders price, from the same three blocks every catastrophe model uses. Teaching model with stated illustrative values, not a prediction.

Controls

Typical annual hazard intensity (location)
1.00 intensity index
Spread of extremes (scale)
0.80 intensity index
Intensity at which half the value is lost
4.00 intensity index
Dispersion of vulnerability
0.55
Share of value in the hazard footprint
40%
Protection standard (return period)
50 years

Readouts

Average annual loss
0.51% of value
Loss at 1 in 100 years
24.5% of value
Loss at 1 in 250 years
28.4% of value
Intensity at 1 in 100 years
4.68 intensity index
Numbers, methods and sources
Return period (years)Intensity (intensity index)Loss (% of value)
10.090.00
21.270.00
41.910.00
72.470.00
133.000.00
243.510.00
444.020.00
824.5323.55
1545.0326.44
2875.5328.87
5366.0330.88
1,0006.5332.53

Methods

  1. Gumbel extreme-value hazard Gumbel (1958), Statistics of Extremes, Columbia University Press
  2. Lognormal fragility (vulnerability) FEMA (2003), HAZUS-MH Technical Manual
  3. Exceedance-probability curve and average annual loss Grossi and Kunreuther (2005), Catastrophe Modeling, Springer
  4. Levee effect Di Baldassarre and others (2013), Socio-hydrology, HESS 17
  5. Uncertainty fan (parameter Monte Carlo) Spiegelhalter, Pearson and Short (2011), Visualising uncertainty about the future, Science 333
  6. One-at-a-time sensitivity (tornado) Saltelli and others (2008), Global Sensitivity Analysis: The Primer, Wiley

Data

The model runs on the teaching values set by the controls. To calibrate it for a place, read it against these admitted layers and series, which this page's map can draw:

  • Rivers Natural Earth
  • Urban extents Natural Earth
  • Cities Natural Earth
  • Earthquakes M4.5+, past week (USGS) U.S. Geological Survey · register usgs.earthquake.summary-feeds
  • Rain rate, last half hour (IMERG) NASA GPM IMERG Early · register nasa.gibs.context-live-layers
  • River discharge forecast, 30 days with range (GloFAS via Open-Meteo) Open-Meteo.com (CC BY 4.0), Copernicus GloFAS · register open-meteo.public-pages
  • Built-up and settlement extent, 2010 (HBASE, Landsat) CIESIN/Columbia, NASA SEDAC HBASE · register sedac.context-urban-layers
Loss exceedance, average annual loss and probable maximum loss. Illustrative teaching model: it runs on the values set by the controls, not on measured data. Methods: Gumbel extreme-value hazard (Gumbel (1958), Statistics of Extremes, Columbia University Press); Lognormal fragility (vulnerability) (FEMA (2003), HAZUS-MH Technical Manual); Exceedance-probability curve and average annual loss (Grossi and Kunreuther (2005), Catastrophe Modeling, Springer).
06Validation

How results are checked.

Analyses are checked through sensitivity analysis, peer review and stakeholder scrutiny. Retrospective review compares decisions with outcomes.

CheckHow it is done
Values explicitWeights and priorities are stated by the decision maker
RobustnessChoices are tested across scenarios and models
Hindsight separatedPast decisions are judged on information available at the time

Results depend on elicited probabilities and preferences that may be biased. Deep uncertainty can make expected value comparisons misleading.

07Exposure, loss and capital

What it means for exposure, loss and capital.

The exposure, loss, scenario and capital views a risk officer, supervisor or ministry of finance would ask for, with the frameworks they report against. Structures follow supervisory and actuarial practice. Values are illustrative: never prices, ratings or advice.

Financing instruments by layer

How retention and transfer instruments could share losses from decision analysis under uncertainty for disaster risk finance, from frequent to extreme.

Retention and reservesFrequent, low severityContingent creditModerateParametric cover and risk poolsSevereReinsurance and catastrophe bondsRare, extremeResidual lossBeyond all layersseverity rises upward
LayerWho holds the riskSpeed of fundsMain limit
Retention and reservesBudget, contingency fundsImmediateSize of the budget
Contingent creditDevelopment banks, ministries of financeDays to weeksDebt capacity
Parametric cover and risk poolsRegional pools, insurersDays, on a triggerBasis risk
Reinsurance and catastrophe bondsReinsurers, capital markets investorsWeeks to monthsCost of capital
Residual lossHouseholds, firms, humanitarian fundingUncertainUnfunded
Risk layering as described in disaster risk finance practice; instruments are illustrative of the structure, not offers, prices or advice.
NGFS climate scenarios · Network for Greening the Financial SystemIFRS S2 Climate-related Disclosures · ISSBTCFD recommendations · Financial Stability Board TCFDPrinciples for the effective management of climate-related financial risks · Basel Committee on Banking Supervision
09Stewardship

Who maintains the method.

Systemic Risk Management stewards decision analysis under uncertainty for the Consortium and reviews how it is applied across platforms.

11Questions

Questions and answers.

What are the limits of decision analysis under uncertainty in this field?
Results depend on elicited probabilities and preferences that may be biased. Deep uncertainty can make expected value comparisons misleading.
How are results checked?
Analyses are checked through sensitivity analysis, peer review and stakeholder scrutiny. Retrospective review compares decisions with outcomes.
Are the values on this page real?
The data names, roles and checks are real descriptions of practice. The canvas shows a design of the method's use, not a run; no result is reported here.
Where else is this method applied?
The canonical method page lists every platform that applies it.
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