ORD concepts

ORD covers a suite of model outputs across multiple perspectives and calculations. The most widely used are the exceedance-probability (EP) curves. This page explains the concepts that the result tables and fields encode.

Perspectives

Results are produced at one or more financial perspectives:

• GUL — ground-up loss (before insurance terms).

• IL — insured loss (after applying policy terms).

• RI — reinsurance / net-of-reinsurance loss.

The same table schemas apply at every perspective; the perspective is a property of the output file, not of the schema.

Table families

The result tables come in families distinguished by what they summarise and how the loss distribution is represented:

• Event loss tables (SELT, MELT, QELT) — loss per event.

• Period loss tables (SPLT, MPLT, QPLT) — loss per event within each period/year.

• Exceedance-probability tables (EPT, PSEPT) — loss by return period.

• Average loss table (ALT) — expected (annual average) loss.

Within event and period families the prefix denotes the representation: Sample (raw samples), Moment (mean/SD statistics), Quantile (user-specified quantiles). See the tables reference for the full catalogue.

EP curves: EPType and EPCalc

The EPT is a set of user-specified percentiles of (typically annual) loss. Each row is keyed by two coded dimensions.

EPType — which exceedance metric:

EPType	Meaning
1	OEP — Occurrence EP: the largest single event loss in a year.
2	OEP TVaR — tail value-at-risk of the OEP (mean of losses beyond the return-period threshold).
3	AEP — Aggregate EP: the sum of all event losses in a year.
4	AEP TVaR — tail value-at-risk of the AEP.

EPCalc — how the loss for a year is calculated:

EPCalc	Meaning
1	Mean damage — loss from the event mean damage (numerical integration of the damage distributions).
2	Full uncertainty — computed across all samples (samples treated as repeat years); the most accurate single EP curve.
3	Per-sample mean — the average, at each return period, of the per-sample EP curves (see PSEPT).
4	Sample mean — loss from the statistical sample event mean.

ReturnPeriod is the reciprocal of the exceedance percentile; Loss is the modelled loss.

The PSEPT (per-sample EPT) computes the same percentiles separately for each sample, giving one curve per sample — the distribution behind the single EPCalc curves above.

Special sample indices

Sample-level tables use reserved negative SampleId (sidx) values for summary statistics:

sidx	Meaning
-1	mean
-2	standard deviation
-3	impacted exposure
-4	chance of loss
-5	maximum loss

Summary levels

Results can be output at a variety of summary levels — single-way (e.g. by OccupancyCode) or multi-way (e.g. CountryCode × AreaCode × LOB). Each summary is represented by two files:

• a link file mapping each SummaryId to the grouping key(s), and

• a results file carrying the loss values keyed by SummaryId.

This keeps the result tables narrow and uniform regardless of how many dimensions the user summarised by. For example, a multi-way summary by CountryCode × AreaCode × LOB has a link file with those three columns against SummaryId, and result tables that reference only SummaryId.