GCRI · How Nexus works
Test
Testing puts an analysis, and the institutions that would use it, under controlled pressure before a real event does. Exercises, scenario drills and side-by-side comparisons are run so that failure is cheap and recorded.
01Six pillars
This step runs in Universe.
Where a build is tested under controlled conditions with independent evaluators, so a method’s skill is measured, not assumed. Go to Universe.
Select pillars · hover lines16 / 18 handoffs
handoff in playrecorded handoffno direct handoff
Programme yearAll phases
L · F · U · S · R · A
- Pillars
- 5 of 6
- Handoffs
- 16 of 18
- Loops
- 16 closed
Handoffs in play
- F01Universe → Foundry · Admitted mission becomes a cycle project with a decision caseReadiness preparation
- F02Foundry → Universe · Core Build Report and go or no-go evidenceControlled build
- F03Foundry → Reports · Sealed observations and indicator series behind a profileCloseout
- F04Universe → Reports · After-action and scenario findings for chapters 10 and 13After-action review
and 12 more
- LabsWhere questions become experiments and prototypes: new methods, data and tools are tried in the open, with their limits on record, before the Foundry builds them, under the Nexus Consortium.Labs at GCRI: Labs
- FoundryWhere methods, data and models become reproducible builds, each run with its inputs, version and limits on record.Foundry at GCRI: Foundry
- UniverseWhere a build is tested under controlled conditions with independent evaluators, so a method’s skill is measured, not assumed.Universe at GCRI: Universe technical officeuniverse.nexus
- Nexus StandardsWhere methods, identifiers and data schemas are codified in the open and corrected when a test finds a fault.Nexus Standards
- ReportsWhere findings are published with their method, uncertainty and evidence class, and corrected as new versions.Reports at GCRI: PublishReports
- Risk AcademyWhere methods and systems are taught on real data and real places, by working the case, on Risk Academy.Risk Academy
02Kinds of test
From desk review to full exercise.
| Test | What it shows | Reference practice |
|---|---|---|
| Hindcast | Whether a model reproduces a past event it was not tuned on | Split-sample validation in hydrology and climate science |
| Tabletop exercise | Whether decision-holders can use the outputs under time pressure | Exercise programmes in ISO 22301 business continuity and civil protection practice |
| Scenario stress test | How a system behaves under severe but plausible combinations | Reverse and compound stress testing in financial and infrastructure practice |
| Red team | How an AI or data system fails under adversarial use | NIST AI RMF measure function; adversarial testing |
03Workspace
The workspace for the test step.
GCRI · GCRI · Exercise controlIllustrative
Exercise control
Methods council · Example exercise interface, not a record
Example interfaceGCRI · GCRI
What the screen records
- Injects delivered
- count against the planned injects
- Median response
- minutes, per player cell
- Observer notes
- count, observers first
- Stand-down
- planned day and hot wash
Inject timeline
example sequence
- 09:00INJ-1Scenario opens: Methods council
- 10:30INJ-2Independent reviewer receives first signal
- 12:15INJ-3Escalation: second system affected
- 14:00INJ-4Media query and public message
- 16:30HOTHot wash, observers first
Player cells
| Programme owner | injects, response time, state |
| The Global Centre for Risk and Innovation (GCRI) technical office | injects, response time, state |
| Independent reviewer | injects, response time, state |
| Competent authority | injects, response time, state |
GCRI · Exercise control. Exercise control: example names and illustrative values, not a record.
04Universe
The annual programme where tests are run.
Controlled tests are scheduled through Universe, the annual programme governed at the Global Risks Forum (GRF). GCRI is its technical office: it designs scenarios, prepares data, keeps the run log and writes the technical after-action review. A test result is an observation about a system under stated conditions; it is never a certification of that system.
05Process
How the process runs.
Process
Test: Bank stress test
The Basel stress testing principles describe severe but plausible scenarios, a method to quantify impact, and use of results; hurdles depend on the exercise.
01 Scenario and balance sheet
- 01Scenario designDataset · National DeskScenarios capture the material risks identified, with a narrative explaining how. They are severe but plausible and varied.
- 03Balance sheet projectionModel · National DeskMethods range from point-in-time static approaches to dynamic simulations that reflect future business activities and management actions.
02 Risk impacts
- 04Credit lossesModel · Credit risk functionCredit risk is one risk the scenario must capture. Banks also keep a model inventory and a validation function for stress models.
- 05EarningsModel · National DeskThe risk identification process includes earnings vulnerabilities. Net interest income under a rate path is one common view.
- 06Market and counterparty lossesModel · National DeskMarket stress tests supplement value-at-risk models with factor shocks or integrated scenarios, historic or hypothetical.
03 Capital and actions
- 02Management actionsStep · National DeskWhere management actions enter supervisory submissions, authorities check they fit the bank’s other strategic plans, such as recovery plans.
- 07Compare projected capital with requirementsStep · National DeskStress tests quantify risks and inform their understanding. Depending on objectives, they may or may not use hurdle rates or thresholds.
04 Authority
- 08Authority use of the resultsDecision · National DeskAuthorities may use results as one supervisory input. For capital adequacy, they consider the response to deficiencies.
Outline of an external standard or method, from its public sources. It describes what the framework says, not a record of any run. It does not show that Nexus or any partner performs, certifies or approves a step. A gate is a step of the method, never a Nexus approval.
06Across the institutions
Each pillar’s contribution.
07Next
Then: publish.
08Sources
Where this page’s references lead.
The bodies and documents this page is read against. Status and editions change; each link goes to the issuing body.
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