Margin driver contribution

Margin driver contribution is one of Demiton's published registers for Australian civil construction. Predicted contribution of each cost or revenue driver to a project's margin, by period. Demiton keeps it current from the systems a contractor already runs and publishes the record's shape as a versioned JSON Schema, so the same question works whichever system produced the record.

Part of Projects in the register catalog.

Register ID

margin_driver_contributionUse this name to ask for the register. The API calls it a shelf ID.

Each record is

An eventSomething that happened at a point in time.

Status

DeclaredDefined, and fills when a source produces its first record.

Data

OrganisationPrivate to each organisation's own workspace.

Version

v1 (1.0.1)Current version.

Download JSON SchemaSee an example record

Connectors

Connected today

Demiton keeps this register current from these systems now.

No system fills this register yet.

On the roadmap

Systems in the planned connector rollout that can fill this register. Partial means the system holds only some of its fields.

None planned yet.

Fields

13 fields: 9 required, 4 optional.

Required

Every record carries these fields.

fact_classText

Provenance marker distinguishing a model output from an observed fact.

Example: predicted

project_idText

The project the prediction is about; the fact's subject anchor.

Example: BWG-2025-001

model_versionText

The fitted model version that produced these values; part of the fact identity.

Example: margin-driver-v3

financial_periodText

The period the prediction is made for; part of the grain.

Example: 2026-07

driver_delay_hoursDecimal numberUnit: hours

Predicted margin contribution attributed to site delay hours.

Example: 18

driver_labour_hoursDecimal numberUnit: hours

Predicted margin contribution attributed to labour hours.

Example: 1240.5

predicted_margin_pctDecimal numberUnit: pct

The model's predicted project margin at the scoring cut.

Example: 8.4

driver_cost_growth_pctDecimal numberUnit: pct

Predicted margin contribution attributed to cost growth.

Example: 3.1

driver_variation_countDecimal number

Predicted margin contribution attributed to variation signals.

Example: 2

Optional

Present when the source system records them.

feature_valuesGroup of fields

The raw feature inputs the contributions were derived from.

training_as_ofDate and timeISO 8601, with time zone

The transaction-time cutoff the model trained on.

legal_entity_idText

The legal entity whose project the prediction belongs to.

n_training_rowsWhole numberUnit: count

Number of project rows the model fitted on.

Filed against

Records are indexed along these dimensions, so they can be asked for by any of them.

• Legal entitycontext for the record, from When known
• Financial periodcontext for the record, from Always set

Example record

A sample from Bridgeworks Group, Demiton's demonstration company. The values are illustrative; the shape is exactly what the contract describes.

margin_driver_contribution.example.json

{
  "driver_cost_growth_pct": 3.1,
  "driver_delay_hours": 18,
  "driver_labour_hours": 1240.5,
  "driver_variation_count": 2,
  "fact_class": "predicted",
  "financial_period": "2026-07",
  "model_version": "margin-driver-v3",
  "predicted_margin_pct": 8.4,
  "project_id": "BWG-2025-001"
}

Use this contract

The contract is a standard JSON Schema (draft 2020-12) document, so any JSON Schema validator can check a record against it. Keywords starting with x-demiton- add Demiton's own meaning, such as units and requiredness, and validators ignore them.

Schema URL

https://docs.demiton.io/registers/margin_driver_contribution/v1.json

Show the full JSON Schema

Loading the schema…