GCRI · Foundry

Grix evidence

A risk figure is only as good as the record behind it. The Global Risks Index (NXS-GRX), the risk-data and semantic system of Foundry, is designed to register, standardise, link and trace risk data so that every statement can be followed to its source and re-run. This page sets out how evidence degrades through a pipeline, from licence and meaning to place, time and scenario, which NXS-GRX binds in Chronotopes, and what data stewards and reviewers need before a product leaves a project.

02The question

Grix evidence: how the risk develops.

Data, ontology, Chronotopes and lineage. The dossier below sets out how the risk develops, what is measured, where the data come from, how it is modelled and who decides.

Mechanism

Meaning drifts across sources

Two datasets both say exposure, affected population or asset and mean different things. Harmonising categories makes them combinable and can hide the difference that mattered. An ontology states the mapping so that it can be inspected and contested.

Mechanism

Silent transformation

A unit conversion, a join on a mistyped key, a filled gap or a reprojection happens inside a pipeline step that nobody records. The output looks clean; the error stays invisible until someone tries to reproduce it from the original.

Mechanism

Time and scenario collapse

An asset’s state before an event, after it and under a what-if branch are three different records. Stored as one, history is overwritten. Chronotopes bind each record to place, time and scenario so the states coexist without conflict.

Mechanism

Corrections must propagate

When a source is corrected, every index, map and loss estimate derived from it is stale. Without lineage nobody knows which products to recompute, and the wrong figure keeps circulating in briefings long after the source was fixed.

03Monitor

GIS and modelling workspace.

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

GIS and modelling workspace: the screen’s structure, terms and states for Grix evidence.Example names and illustrative values; a design, not a record or a live system.
04In the five domains

NXS-GRX is designed to hold evidence from every domain with its labels.

05Methods and evidence

How grix evidence is modelled, measured and tested.

The model, its assumptions, its data and its uncertainty, in the form a scientist or engineer would check. Structures follow published methods. The values drawn are illustrative, not findings.

Model, equations and assumptions

The model structure used for grix evidence, the assumptions it makes and how each is tested.

Risk of element iRi = f(Hi, Ei, Vi, Ci)hazard, exposure, vulnerability and coping capacity
Expected annual lossEAL = ∑k pk · Lkover events k with annual probability pk
Coupled systemsxt+1 = A xt + B ut + εtA carries the couplings, u the shock, ε the error
AssumptionWhy it is madeHow it is tested
Hazard and exposure are independent within an eventKeeps the loss integral tractableCompare with a copula fit on joint records
Couplings are linear near the operating pointLets shocks propagate through APerturb beyond the linear range and compare
Vulnerability curves transfer between placesLocal curves are rarely availableValidate against observed losses where they exist
Inputs
versioned datasets with provenance
Outputs
distributions, never single numbers
Code
released with the model card and tests
Reproduction
same data, code, environment and seed
Standard risk and state-space formulations; the assumptions listed are typical of the method, stated for review, not results.
FAIR guiding principles · GO FAIR and FORCE11W3C PROV · World Wide Web ConsortiumGuidance on consistent treatment of uncertainties · IPCCCEOS Analysis Ready Data · Committee on Earth Observation Satellites
06Indicators

What is measured, and how well.

Each indicator carries its unit, its cadence, the kind of source behind it and the evidence label a value would carry. No values are shown: a programme supplies them under its own authority.

IndicatorUnitCadenceSource typeLabel
Sources with a complete source passportproportion of registered sourcesmonthlySource registerDECLARED
Records failing shape validation at ingestcount per batchper ingestOntology shape validationOBSERVED
Published products with end-to-end lineageproportion of productsper releaseLineage graphOBSERVED
Products affected by a source correctioncount per correctionper eventLineage impact queryOBSERVED
Time from source correction to recomputationdaysper eventPipeline and release recordsOBSERVED
Records carrying an evidence labelproportion of recordsper releaseRecord metadataOBSERVED
Variables conforming to standard names and unitsproportion of variablesper ingestCF and unit checksOBSERVED
07Sources

Where the evidence comes from.

Named public datasets and institutional records, each with its licence class. Sources by agreement are used only under their terms and never republished.

SourceWhat it givesLicence class
World Bank Open DataDevelopment indicators with documented definitions and sourcesCC BY 4.0
Humanitarian Data Exchange (HDX)Crisis datasets and common operational datasets from humanitarian partnersLicence per dataset
National open data portals and statistical officesPublished statistics, registers and boundariesOpen government licences, per country
CF standard name tableAgreed names and units for climate and forecast variablesFree and open
WikidataLinked identifiers for places, institutions and infrastructureCC0
W3C PROV and DCAT vocabulariesStandard models for provenance and for dataset cataloguesW3C document licence
08Decisions

Who decides, and what the evidence serves.

Foundry prepares evidence. The decisions below are taken by the authorities named, under their own rules, and never by the platform.

Who decidesThe questionEvidence this page serves
Data ownersWhether their data may enter, be standardised, be published or train modelsSource passport, intended uses, derived products
National statistical officesWhether a derived figure may sit beside a published statistic, and how it is labelledMethod, evidence label, and the published figure kept separate
Review leadsWhether a product is fit for releaseLineage, validation results, labels and open corrections
Programme ownersWhether a new index method version is adopted for reportingMethod version history, frozen data cuts and re-run comparisons

Outputs this topic produces

  • Source passports with owner, licence, cadence, authority class and known limits
  • Validated records bound to place, time and scenario
  • Lineage graphs from source record to published figure
  • Correction impact reports listing products to recompute
09Core questions

What data stewards and analysts ask.

  • Where did this value come from, under which licence, and what has been done to it?
  • Do two datasets mean the same thing by “exposure”, “asset” or “affected population”?
  • Which version of the data and which version of the method produced this index?
  • When a source is corrected, which products are affected?
10Mechanisms

Preserve, describe, bind, trace.

  1. 01

    Source passports

    Each source is registered with its owner, licence, access policy, update cadence, authority class and known limits before any record is standardised.

  2. 02

    Originals kept

    Original records are retained unchanged; standardised fields are derived and linked back, never substituted for them.

  3. 03

    Ontology

    The NXS-GRX ontology describes hazards, exposures, vulnerabilities, assets, institutions and their dependencies, with shapes that validate what enters the knowledge graph.

  4. 04

    Chronotopes

    Each risk record is bound to a spatial and temporal frame and a scenario branch, so the same asset can carry different states across time and across what-if branches without conflict.

  5. 05

    Lineage

    Indices and losses are designed to be computed from frozen data cuts with declared methodology versions, so they can be re-run and matched.

11Methods and limits

What the engineering can and cannot do.

The approach draws on established practice: provenance models, semantic web standards for ontologies and shape validation, versioned data lakes and reproducible pipelines. Verification is shown as separate dimensions, integrity, conformance, plausibility, corroboration, method, rights and human review, rather than as one badge, because a record can be well-formed and still wrong.

The limits are real. Ontologies encode choices that some disciplines will contest, and harmonising categories can hide meaningful differences between sources. Lineage shows what was done, not whether it was appropriate. Original source authority is retained: Programme estimates stay labelled as estimates and never replace published figures.

12Methods

How it is studied, and what the methods cannot say.

  1. Data engineering, interoperability and stewardshipValidation at the ingest boundary · Frozen data cuts for reproducible productsApplied here
  2. Systems engineeringCanonical system inventory · Contract-first interfaces · Requirements traced to evidenceApplied here
  3. Geospatial information systemsImagery catalogues through STAC · Exposure overlays with stated aggregationApplied here
  4. Artificial intelligence and machine learningEarth observation models with spatial validation · Model cards and promotion recordsApplied here
13Where this page’s references

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.

14Questions

Questions and answers.

What is a Chronotope?
A binding of a risk record to a spatial frame, a time frame and a scenario branch. It lets the same asset carry its state before and after an event, and under different what-if branches, without one overwriting another.
Why keep original records unchanged?
Because standardisation is a transformation that may later prove wrong. Keeping the original lets anyone re-derive the standardised field, check the mapping and recover from an error.
Is verification a single badge?
No. Integrity, conformance, plausibility, corroboration, method, rights and human review are separate dimensions. A record can be well formed and still wrong, so each dimension is shown on its own.
Does NXS-GRX rank countries?
No. NXS-GRX products describe risk with stated methods and uncertainty for a defined purpose. They are not league tables and do not replace published statistics.
What happens when a source is corrected?
Corrections create new versions with reasons rather than overwriting history, and dependent products can be traced and updated.
Are indicator values shown here?
No. Values appear only in released products, through Registry public records or Reports series.
ReportsContribute

Contribute evidence from this page.

Reports is the Consortium’s quarterly publication. What you know about this subject can become evidence, a case or a correction in the next edition, credited to you and published under CC BY 4.0 where it is your own work.

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