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Simulation Methodology

Published April 2026 — Web3 Certification Board Inc.

1. Purpose and Scope

This page documents the mathematical model, trigger logic, and design assumptions used by the Parametric Insurance Simulator. It is intended for instructors, institutional reviewers, government procurement teams, and any participant who wishes to understand how the simulation produces its outputs.

The simulator uses a weighted multi-variable risk scoring model designed to demonstrate the trigger mechanics of parametric insurance. It is not an actuarial pricing model, does not use historical loss calibration, and does not replicate the legal terms of any real insurance product. All premium amounts, payout figures, and threshold values are representative and illustrative only.

2. Core Model Architecture

Every scenario in the simulator — from the single-variable Drought scenario to the four-variable Glacier, Pacific SIDS, and Sahel scenarios — uses the same underlying calculation pipeline:

  1. Read the current value for each variable from the user's slider position
  2. Calculate an individual severity score for each variable
  3. Combine severity scores into a weighted risk score
  4. Apply the majority trigger rule to decide whether a payout occurs
  5. Multiply the weighted risk score by the maximum payout to produce the final payout amount

3. Variable Severity Calculation

Each variable has a trigger direction — either above a threshold (e.g., wind speed exceeding 120 km/h) or below a threshold (e.g., rainfall falling below 150 mm). The severity formula produces a value between 0 and 1, where 0 means the variable is well within safe range and 1 represents maximum recorded severity.

For variables triggered when the measured value falls below the threshold:

Example: Drought Rainfall, NDVI Pasture Index, Rainfall Anomaly
severity = (threshold − measured value) ÷ threshold
Returns 0 when measured value ≥ threshold (no stress). Increases linearly as the value drops further below threshold. The denominator anchors severity to the threshold level, not the absolute minimum, so a reading of zero produces a severity of 1.0 — full severity.

For variables triggered when the measured value rises above the threshold:

Example: Wind Speed, Water Level, Air Quality Index, Wet-Bulb Temperature
severity = min( (measured value − threshold) ÷ (maximum possible value − threshold), 1 )
Returns 0 when measured value ≤ threshold. Increases as the measured value rises above threshold, reaching 1.0 at the maximum of the variable's range. The min() cap prevents the severity from exceeding 1.0 regardless of input.

4. Weighted Risk Score

Each variable carries a weight that reflects its relative contribution to overall risk. Weights across all variables in a scenario sum to exactly 1.00 (100%). The weighted risk score displayed during the simulation is calculated as:

Risk Score = Σ ( severityi × weighti ) × 100
The result is expressed as a percentage (0–100) and capped at 100. A Risk Score of 0 means no variable is under stress. A Risk Score of 100 means all variables are at their maximum severity simultaneously.

This is the number shown on the Risk Score gauge during the simulation dashboard. It is a live indicator that updates as the user adjusts sliders, before the formal simulation run begins.

5. The Majority Trigger Rule

Parametric insurance in real programmes typically requires a clearly defined trigger condition to be met before any payout is released. The simulator uses a majority trigger rule: a payout only occurs if at least half of the scenario's variables individually cross their respective thresholds.

Trigger activated = ( triggered variables ÷ total variables ) ≥ 0.5

For a 1-variable scenario (Drought): the single variable must trigger (1 ÷ 1 = 1.0 ≥ 0.5).
For a 2-variable scenario (Flood, Livestock): both variables must trigger (2 ÷ 2 = 1.0 ≥ 0.5).
For a 3-variable scenario (Hurricane, Heatwave, Wildfire): at least 2 of 3 must trigger (2 ÷ 3 = 0.67 ≥ 0.5).
For a 4-variable scenario (Glacier, Pacific SIDS, Sahel): at least 2 of 4 must trigger (2 ÷ 4 = 0.5 ≥ 0.5).

If the majority rule is not met, the payout is zero, regardless of how high the weighted risk score is. This models a fundamental property of parametric insurance: the trigger condition is binary and pre-agreed. It cannot be overridden by degree of suffering or subjective assessment of need — a feature that eliminates moral hazard and disputes, but also introduces basis risk when real losses occur without the index crossing the threshold.

6. Payout Calculation

When the majority trigger rule is satisfied, the payout is calculated directly from the weighted severity of all variables:

Payout = round( Max Payout × weighted severity )

Where weighted severity = Σ ( severityi × weighti ) — the same value used in the Risk Score before being multiplied by 100. The payout therefore scales continuously with severity, from a small amount just above the trigger threshold up to the full maximum payout when all variables are at peak severity.

Coverage Tier Adjustment

The simulator offers three coverage tiers — Basic, Standard, and Comprehensive. Each tier applies a threshold multiplier to the base trigger threshold, and sets a different maximum payout ceiling:

TierThreshold AdjustmentEffectMax Payout
BasicMultiplier < 1.0 (typically 0.8–0.85×)Trigger activates only during more extreme events; lower ceiling~60% of Standard
Standard1.0× (baseline)Default threshold and payout as documented per scenarioBaseline (100%)
ComprehensiveMultiplier > 1.0 (typically 1.15–1.2×)Trigger activates earlier (more sensitive); higher ceiling~150–160% of Standard

Exact multipliers and payout ceilings vary by scenario to reflect the real-world economics of each risk type. The per-scenario variable specifications in Section 8 document the Standard tier values.

7. Worked Example: Flood Scenario

To make the model concrete, here is a step-by-step calculation for the Flood Insurance scenario using Standard coverage, with the conditions from the 2020 Kampong Luong flood used as a challenge scenario in the simulator:

Inputs

  • Water Level: 4.2 m (threshold 3.5 m, above-type, weight 0.60)
  • Rainfall Duration: 52 hours (threshold 36 hours, above-type, weight 0.40)
  • Max Payout: $5,000

Step 1 — Severity per variable

Water Level severity = (4.2 − 3.5) ÷ (6.0 − 3.5) = 0.7 ÷ 2.5 = 0.28

Rainfall Duration severity = (52 − 36) ÷ (72 − 36) = 16 ÷ 36 = 0.44

Step 2 — Weighted severity

(0.28 × 0.60) + (0.44 × 0.40) = 0.168 + 0.176 = 0.344

Step 3 — Risk Score (display)

0.344 × 100 = 34%

Step 4 — Majority trigger rule

Both variables triggered (4.2 > 3.5 ✓, 52 > 36 ✓). Triggered: 2 ÷ 2 = 1.0 ≥ 0.5 ✓

Step 5 — Payout

round($5,000 × 0.344) = $1,720

This illustrates a key characteristic of the model: even with both variables clearly above their thresholds, the payout is $1,720 — not the full $5,000. The full maximum payout is only reached when both variables simultaneously hit the top of their respective ranges (water level at 6.0 m and duration at 72 hours).

8. Per-Scenario Variable Specifications

The table below documents the Standard tier trigger parameters for all nine scenarios. Click any scenario to expand its full variable specification.

9. What the Simulator Simplifies

Understanding what the simulator does not model is as important as understanding what it does. The following simplifications are intentional and appropriate for an educational tool:

No full actuarial loss calibration

Real parametric programmes set their trigger thresholds and maximum payouts through actuarial modelling of historical loss data — typically 20–50 years of event records correlated with insured losses. The simulator uses representative threshold values chosen to reflect real programme designs (e.g., IBLI's NDVI threshold in Marsabit, CCRIF's wind speed parameters) but does not replicate the underlying statistical models. The Policy Design Lab does, however, calibrate against a curated set of real historical events with documented loss outcomes (see Section 10) so that the basis-risk analysis is grounded in actual occurrences rather than hypotheticals.

No premium pricing model

Premiums in the simulator are illustrative. Real premiums are priced from the expected annual payout (probability of trigger × average severity) plus reinsurance costs, expenses, and a risk margin. The simulator does not model probability distributions or return periods.

No reinsurance or capital structure

Real programmes typically transfer risk to reinsurance markets or catastrophe bond investors. The simulator treats the insurer as a single entity with unlimited capacity — sufficient for demonstrating trigger mechanics but not capital structure.

Linear severity scaling

The severity formulas use linear interpolation between the threshold and the range boundary. Real programmes may use non-linear severity curves — for example, doubling the payout acceleration beyond a certain level of wind speed — to better reflect how physical damage scales with hazard intensity.

Quantified basis risk (in the Policy Design Lab)

The public scenarios demonstrate basis risk conceptually — showing cases where the index does not trigger despite real losses. The Policy Design Lab goes further: its Basis Risk Explorer classifies a curated set of real historical events into a confusion matrix (covered losses, missed losses, false alarms, and correct non-payments) and reports detection rate, miss rate, and false-alarm ratio for any threshold configuration. These figures are computed over the curated event set rather than a complete spatial loss census, so they are indicative measures of the design trade-off — not a programme-grade basis-risk certification.

10. Data Sources and Oracle Concept

In real parametric programmes, the data pipeline from measurement to payout is critical for trust. Each scenario in the simulator is modelled on data sources used in operational programmes:

ScenarioReal Data Source BasisReal Programme Reference
DroughtCHIRPS (Climate Hazards Group InfraRed Precipitation with Station data)ACRE Africa, Kilimo Salama (Kenya/Ethiopia)
FloodRiver sensor networks + satellite SAR imageryWFP Forecast-based Financing (Bangladesh, Cambodia)
HurricaneNOAA National Hurricane Center wind speed recordsCCRIF SPC (Caribbean, since 2007)
HeatwaveWMO wet-bulb temperature station dataAhmedabad Heat Action Plan; India National Heat Action Programme
WildfireEPA AQI monitoring network + NASA FIRMS fire detectionEmerging US/Australian state-level parametric smoke programmes
GlacierESA CryoSat-2, GRACE-FO satellite + WMO glacier inventoryEmerging slow-onset L&D instruments; GCF feasibility pilots
Livestock (IBLI)MODIS Terra/Aqua NDVI + CHIRPS precipitation anomalyIBLI (Marsabit County, Kenya; Borana Zone, Ethiopia) — ILRI/Cornell
Pacific SIDS Ocean CoverageNASA/CNES altimetry (TOPEX, Jason-3) + Argo ocean floats + NOAA tide gauges + satellite reef spectral analysisPCRAFI (Pacific Catastrophe Risk Assessment and Financing Initiative); AOSIS Loss & Damage proposals; GCF SIDS access pathways
Sahel Multi-Year DroughtAfrica Risk View (ARV) satellite rainfall + CHIRPS + MODIS/Sentinel-2 NDVI + FEWS NET IPC food security assessmentsAfrican Risk Capacity (ARC) — member states including Niger, Mali, Senegal; Sahel Alliance multi-year drought instruments

Dataset provenance for the Policy Design Lab calibration

The Policy Design Lab's historical event set and Basis Risk Explorer draw on the specific datasets below. Each entry documents the dataset, version, provider, native resolution, baseline period, and a formal citation so that every calibrated value is traceable to its source.

ScenarioDataset & VersionProvider / InstitutionResolutionBaselineCitation
DroughtCHIRPS — Climate Hazards Group InfraRed Precipitation with Station data (v2.0)Climate Hazards Center, UC Santa Barbara (CHC/UCSB)0.05° (~5 km); Daily, pentadal, dekadal, monthly, seasonal1981–2010 climatological mean (record from 1981–present)Funk, C. et al. (2015). The climate hazards infrared precipitation with stations. Scientific Data 2, 150066. https://www.chc.ucsb.edu/data/chirps
FloodRiver-stage gauges + satellite flood mapping (Copernicus Sentinel-1 SAR / EMS, Dartmouth Flood Observatory) (Copernicus EMS Rapid Mapping; DFO event archive)National hydro-meteorological services; Copernicus Emergency Management Service (ECMWF/EC); Dartmouth Flood ObservatoryGauge point; ~10–20 m SAR flood extent; Sub-daily gauge readings; per-event satellite acquisitionLocal alert-level stage (3.5 m reference) per national hydromet standardsCopernicus Emergency Management Service (EMS) flood mapping; Brakenridge, G.R., Dartmouth Flood Observatory event archive. https://emergency.copernicus.eu/
HurricaneNOAA HURDAT2 best-track + parametric wind/surge index (CCRIF SPC model) (HURDAT2 (Atlantic); CCRIF SPC parametric products)NOAA National Hurricane Center; Caribbean Catastrophe Risk Insurance Facility (CCRIF SPC)Track point + modelled wind/surge footprint; 6-hourly best-track fixesSaffir–Simpson category thresholds; CCRIF index calibrationLandsea, C.W. & Franklin, J.L. (2013). Atlantic Hurricane Database Uncertainty (HURDAT2). Mon. Wea. Rev. 141. https://www.nhc.noaa.gov/data/
HeatwaveERA5 reanalysis — wet-bulb temperature & heat duration (ERA5 (C3S))ECMWF / Copernicus Climate Change Service (C3S)0.25° (~31 km); Hourly (1940–present)1991–2020 climatologyHersbach, H. et al. (2020). The ERA5 global reanalysis. Q. J. R. Meteorol. Soc. 146, 1999–2049. https://cds.climate.copernicus.eu/
WildfireAir Quality Index (ground PM2.5 monitors) + NASA FIRMS active fire (MODIS/VIIRS) (FIRMS MODIS C6.1 / VIIRS)NASA FIRMS / LANCE; national air-quality monitoring networks375 m (VIIRS) / 1 km (MODIS) active fire; monitor-point AQI; Near-real-time (multiple daily passes)US EPA AQI breakpoints (PM2.5)NASA FIRMS (Fire Information for Resource Management System); US EPA AQI methodology. https://firms.modaps.eosdis.nasa.gov/
GlacierSatellite glacier mass-balance + snowpack / streamflow gauges (GLOF monitoring) (Hugonnet et al. (2021) geodetic mass balance; national snow/hydro networks)Randolph Glacier Inventory community; national hydrological services (Andes)~100 m DEM differencing; basin-scale hydrology; Annual / seasonal2000–2019 geodetic baselineHugonnet, R. et al. (2021). Accelerated global glacier mass loss in the early twenty-first century. Nature 592, 726–731. https://doi.org/10.1038/s41586-021-03436-3
Livestock (IBLI)MODIS Vegetation Indices (NDVI) + CHIRPS rainfall (MOD13Q1 V061 (NDVI); CHIRPS v2.0 (rainfall))NASA LP DAAC (MODIS); CHC/UCSB (CHIRPS); IBLI programme by ILRI250 m (MOD13Q1 NDVI); 16-day composite (2000–present)NDVI long-term seasonal mean; IBLI strike at ~20th–25th percentileDidan, K. (2021). MOD13Q1 MODIS/Terra Vegetation Indices 16-Day L3 Global 250m V061. NASA LP DAAC. DOI:10.5067/MODIS/MOD13Q1.061 https://doi.org/10.5067/MODIS/MOD13Q1.061
Pacific SIDS OceanSatellite altimetry sea level + NOAA Coral Reef Watch + tide gauges + wave model (C3S sea-level; NOAA CRW Degree Heating Weeks; PCRAFI)Pacific Catastrophe Risk Assessment & Financing Initiative (PCRAFI); NOAA Coral Reef Watch; Copernicus C3S~0.25° altimetry; 5 km coral bleaching; gauge-point salinity; Daily–monthlySatellite-era mean sea level; CRW bleaching thresholdsNOAA Coral Reef Watch; PCRAFI (World Bank / SPC). Copernicus Marine / C3S sea-level products. https://coralreefwatch.noaa.gov/
Sahel Multi-Year DroughtAfrica RiskView (WRSI rainfall) + CHIRPS + MODIS NDVI (Africa RiskView (ARC); CHIRPS v2.0; MOD13Q1 V061)African Risk Capacity (ARC); CHC/UCSB; NASA LP DAAC~5 km rainfall; 250 m NDVI; Dekadal / seasonalWRSI long-term mean; ARC return-period calibrationAfrican Risk Capacity (ARC) — Africa RiskView technical framework; CHIRPS (Funk et al. 2015). https://www.arc.int/

Index values for named events are calibrated to the documented severity of each event (for example, a drought season expressed as a percentage of the long-term mean rainfall in the cited dataset). Where an independently verifiable gridded cell value is not available, a representative figure consistent with the cited dataset and event is used and labelled as such in the Lab. Annual probabilities shown in the Lab are indicative inputs to the premium model derived from each dataset's historical distribution or documented return periods — they are illustrative, not actuarial rates.

In smart contract implementations, a data oracle is the service that feeds verified, tamper-resistant data from these external sources into the on-chain trigger logic. The oracle acts as the trusted bridge between the physical world and the automated payment system — its integrity is what makes parametric insurance trustworthy without requiring a loss assessor.

11. Simulation Phases

When the user clicks "Run Simulation," the simulator progresses through six phases designed to mirror the sequence a real smart contract would execute. Each phase is presented with a time delay to create a realistic representation of the verification pipeline:

  1. Initializing — Smart contract parameters and coverage terms confirmed
  2. Collecting Data — Oracle requests data from the designated source (e.g., CHIRPS rainfall feed)
  3. Verifying Sources — Multiple data feeds are cross-referenced; anomalies flagged
  4. Calculating Risk — Weighted severity calculation executed on-chain
  5. Analyzing Triggers — Majority trigger rule evaluated against the computed risk score
  6. Settlement — Payout decision recorded to the blockchain transaction log and funds released (if triggered)

The blockchain transaction record generated during the simulation — including hash, block number, timestamp, and all variable values — is illustrative of the on-chain audit trail that makes parametric payouts verifiable and dispute-free.

12. Educational Use Statement

The Parametric Insurance Simulator is a training tool produced by the Web3 Certification Board Inc. (W3CB) for use in policy training programmes, university courses, and professional development contexts. The simulation model, scenario parameters, and all associated content may be cited in academic and policy work with attribution to W3CB.

Outputs from the simulator — including payout calculations and risk scores — are not evidence of insurability, actuarial soundness, or real programme performance. No reliance should be placed on simulator outputs for actual insurance decision-making. See the Terms of Use and regulatory disclaimers in the application footer.

Questions regarding the simulation model or requests to license the methodology for training programme development should be directed to the Web3 Certification Board Inc.

For educational use only. No licensed insurance product is offered or implied by this simulator. All premiums, payouts, and thresholds are illustrative figures only. This application is not regulated by, affiliated with, or approved by any financial services authority, including the US NAIC, UK FCA, EU EIOPA, Singapore MAS, Hong Kong SFC, or ASIC (Australia).

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