Aggregate risk register copula

Aggregate risk-register occurrence and lognormal severity marginals through a validated Gaussian copula into expected loss, VaR, CVaR, dependence amplification, and tail shares.

What it's for

Turns a flat risk register into a dependence-aware financial loss distribution, showing executives which risks dominate the severe portfolio tail.

What you give it

Inputs split into evidence read from your connected systems, calibration your team owns, and numerical controls that affect precision but never the result's meaning.

Field Type Role Required
confidence_level number ≥ 0.5, ≤ 0.999 Your calibration Optional
correlation_matrix array of array ≥ 2 items Evidence Yes
max_detail_rows integer ≥ 1, ≤ 500 Numerical control Optional
risks array of objects (4 fields) ≥ 2 items Evidence Yes
seed integer ≥ 0, ≤ 4294967295 Numerical control Optional
simulation_draws integer ≥ 1000, ≤ 200000 Numerical control Optional

Each risks record

Field Type Required
id string (non-empty) Yes
occurrence_probability number (≥ 0, ≤ 1) Yes
severity_coefficient_of_variation number (≥ 0, ≤ 100) Yes
severity_mean number (≥ 0) Yes
Example input
{
  "correlation_matrix": [
    [
      1,
      0.5,
      0.3
    ],
    [
      0.5,
      1,
      0.4
    ],
    [
      0.3,
      0.4,
      1
    ]
  ],
  "risks": [
    {
      "id": "outage",
      "occurrence_probability": 0.2,
      "severity_coefficient_of_variation": 0.5,
      "severity_mean": 100
    },
    {
      "id": "security",
      "occurrence_probability": 0.1,
      "severity_coefficient_of_variation": 1,
      "severity_mean": 300
    },
    {
      "id": "vendor",
      "occurrence_probability": 0.15,
      "severity_coefficient_of_variation": 0.7,
      "severity_mean": 150
    }
  ],
  "seed": 42,
  "simulation_draws": 5000
}

What you get back

This is the actual output of running the example above — computed by the same function the platform calls, not an illustration.

Example output
{
  "assumptions": [
    "Occurrence probabilities, severity means/CVs, and latent dependence are calibrated on one stable horizon and loss perimeter with consistent zeros, censoring, inflation, and currency.",
    "The Gaussian copula captures only represented latent dependence and has no asymptotic tail dependence; severe common-cause scenarios require explicit stress additions.",
    "Monte Carlo precision, marginal-family choice, parameter uncertainty, nonstationarity, and omitted risks remain outside the point estimates and must be sensitivity-tested."
  ],
  "decision": "aggregate_risk_register_tail_estimated",
  "method": "gaussian_copula_frequency_severity_risk_register_v1",
  "risk_diagnostics": [
    {
      "occurrence_probability": 0.1,
      "portfolio_cvar_tail_share": 0.5889,
      "risk_id": "security",
      "severity_coefficient_of_variation": 1,
      "severity_mean": 300,
      "simulated_expected_loss": 26.2048,
      "standalone_expected_loss": 30
    },
    {
      "occurrence_probability": 0.15,
      "portfolio_cvar_tail_share": 0.2917,
      "risk_id": "vendor",
      "severity_coefficient_of_variation": 0.7,
      "severity_mean": 150,
      "simulated_expected_loss": 23.2596,
      "standalone_expected_loss": 22.5
    },
    {
      "occurrence_probability": 0.2,
      "portfolio_cvar_tail_share": 0.1195,
      "risk_id": "outage",
      "severity_coefficient_of_variation": 0.5,
      "severity_mean": 100,
      "simulated_expected_loss": 18.8873,
      "standalone_expected_loss": 20
    }
  ],
  "simulation_diagnostics": {
    "confidence_level": 0.95,
    "minimum_correlation_eigenvalue": 0.4819732209,
    "seed": 42,
    "simulation_draws": 5000
  },
  "summary": {

Truncated for display — the full payload is 55 lines.

How it works

Statistical audit & measurement — Check whether a number is fit to decide on: coverage, timing, reconciliation, and the gaps a dashboard hides.

  1. 1 Freeze one loss horizon/perimeter, calibrated occurrence and severity marginals, a symmetric positive-semidefinite latent dependence matrix, simulation precision, and random seed.
  2. 2 Simulate correlated occurrence and independent correlated severity latent draws, apply each marginal, aggregate portfolio loss, and calculate expected loss, VaR, CVaR, dependence amplification, and component tail shares.
  3. 3 Stress marginal family, parameter uncertainty, nonstationarity, and explicit common-cause catastrophes because a Gaussian copula has no asymptotic tail dependence.

Before you trust it

Every tool in the catalog ships with the conditions under which its answer is meaningful — and the conditions under which it should abstain instead of guessing.

Assumptions & guardrails

  • Metric definitions, weights, aggregate grain, sampling, missingness, dependence, and comparison windows correspond to the management claim being audited.
  • Risk occurrence, severity, zeros/censoring, currency/inflation, horizon, and latent correlations are calibrated on comparable history or governed expert evidence without double-counted events.
  • Association, instability, or measurement quality is not a causal effect and must not be converted directly into an individual employment decision.
  • Copula output is model-conditional Monte Carlo—not a guarantee—and Gaussian dependence can materially understate joint extremes absent explicit common-cause scenarios.

Minimum evidence

  • risks: at least 2 rows/items
  • correlation_matrix: at least 2 rows/items

How to validate it

Validate on future periods or held-out aggregate units, compare with a simple baseline, and require stability across plausible metric definitions and decision thresholds.

Calibrating it to your org

Same for everyone

The mathematical kernel, validation rules, method version, and JSON output semantics are organization-independent; no tenant-trained coefficients or company benchmark is embedded in the function.

Specific to you

  • calibrated occurrence probability, lognormal severity mean/CV, and positive-semidefinite latent risk correlation matrix
  • risk perimeter, marginal family, dependence estimation, common-cause stresses, parameter uncertainty, confidence level, simulation draws, seed, and validation epoch

Calibration workflow

  1. 1 Define the management decision, target outcome, aggregate unit, privacy boundary, cadence, and prediction/intervention horizon for this organization.
  2. 2 Build a tenant-scoped historical cohort using only information available before each prediction or decision; preserve zero periods, censoring, assignment probabilities, and unresolved outcomes when the method requires them.
  3. 3 Estimate statistical parameters on training history, but obtain costs, utilities, risk tolerance, practical-effect thresholds, capacity, and policy constraints from accountable decision owners.
  4. 4 Validate on later time windows or held-out aggregate units at the deployment grain, against a simple baseline and the function-specific validation strategy.
  5. 5 Deploy only if the returned decision clears evidence, overlap, calibration, robustness, and guardrail checks; warning, unsupported, schema-gap, and fallback decisions are abstentions.
  6. 6 Monitor realized outcomes, data drift, coverage, and decision regret; recalibrate at a governed cadence or after a detected regime/definition change, never merely because a stakeholder dislikes the result.

Call it from your AI

You don't wire up 388 tools in your MCP client. The GitRevio MCP server exposes 18 tools, three of which let an agent search the catalog, read a tool's schema, and run it — so the assistant finds this one on its own.

gitrevio_capabilities_search
  { "q": "aggregate riskregister occurrence and lognormal severity" }
  → finds "aggregate_risk_register_copula"

gitrevio_capability_describe
  { "capability_id": "aggregate_risk_register_copula" }
  → returns the input schema and agent guidance shown on this page

gitrevio_capability_run
  { "capability_id": "aggregate_risk_register_copula", "arguments": { ... } }
  → returns the result shown above

Works in Claude Desktop, Claude Code, Cursor, Cline, Continue.dev, Goose and Aider. See the MCP server.

Related tools

Optimize tail risk budget allocation

Allocate a finite mitigation budget across mutually exclusive component mitigation levels to minimize portfolio CVaR while preserving aligned scenario dependence.

Constrained optimization

Stress test operating plan assumptions

Stress every operating-plan assumption individually and along a common adverse path, exposing remaining outcome headroom and the linear breakpoint at which the plan fails.

Decision analysis

Allocate restless bandit interventions

Allocate scarce recurring interventions across evolving Markov units with Whittle indices, explicit indexability checks, and paired policy simulation.

Sequential Bayesian & bandits

Attribute commercial dependency tail loss

Calculate expected loss, VaR and CVaR for commercial value concentrated in shared technical components, then allocate every modeled tail-loss dollar exactly once across components with normalized negative-log survival hazard rather than overlapping leave-one-out sensitivities.

Forecasting & survival

Audit commercial resilience claim integrity

Audit resilience ROI claims against a unique commercial-source to technical-component graph: recompute each action's avoided loss under joint failure scenarios, cap support at graph-derived value, detect duplicate effects, probability drift and weak evidence, and prevent overlapping component benefits from being sold twice.

Network & dependency analysis

Audit decision rank robustness smaa

Measure rank acceptability, regret, pairwise dominance, and central winning weights under uncertain criterion scores and bounded stakeholder weights.

Statistical audit & measurement

See every tool in Risk, tails & resilience →

Ready to See Your Engineering work clearly?

Request a free demo