Source evidence

Source snapshots record the capture time, source system, coverage dates, record count and freshness state of a measured input. Metric observations connect a metric name and reporting window to both a snapshot and social profile. These links let the Data Analyst answer a practical question: which captured source supports this value for this property and period?

Evidence documents add attachments, external references and verification state for material that needs a person to inspect. The Evidence Coordinator can identify who verified a document and when the underlying document was dated. This is useful when a snapshot is stale, a mapping changes or the reviewer asks for a source receipt before deciding on a profile revision.

• Capture. A snapshot states its source system, coverage window and freshness state.
• Observation. A metric reading points to the profile and snapshot used for its window.
• Verification. An evidence document keeps a reference, attachment and verifier together.

List the source systems that will provide observations and decide how each capture’s coverage window is defined. Agree what Fresh, Stale and Failed mean operationally. The recorded freshness state is a queue signal for people; it should be reviewed with the actual coverage dates and the period the analyst intends to report.

Set a convention for source hashes and external references. They help the team compare captures and locate original files after a later correction. Decide which documents need verification and which person may verify them. The reviewer should be able to distinguish an uploaded document from a checked one when considering a revision.

Capture a source snapshot for a reporting window and attach an observation to it and to a social profile. Enter the metric name, numerator, denominator and value. Then attach a document with an external reference and ask a different person to verify it. Open the observation and trace both links without searching through unrelated properties.

Now mark a second snapshot Stale with a later capture time but a coverage window that misses the reporting period. The analyst should choose the source that actually covers the period and explain the choice to the reviewer. A date alone is not enough; coverage and provenance make the result credible.

• Snapshot Freshness — Review capture sources, coverage windows and freshness states together.
• Observation Windows — Inspect dated metric values with their profile and snapshot links.

The observation collection process prepares source material. Revision review uses that evidence for an independent decision.