Identity and sources

SC01 Distinguish identities by layer

Two assertions can concern the same economic target and still be distinct records. A revised number must not overwrite the old assertion. A transformed expression of one assertion retains that lineage and changes its representation identity. Identifiers and hashes identify records or bytes, not economic equivalence.

SC02 Qualifier placement must preserve economic distinctions

For the included cases, definitions distinguish the measured target, population or institutional coverage, numerator and denominator construction, price/volume valuation, seasonal-adjustment status, statistical form and time construction. Annual-average growth and December-to-December growth are different constructions. Actual period endpoints bind an observation; the construction determines what those endpoints mean. Geography includes the relevant boundary or membership version when that can change, such as EA19.

Nominal versus real, adjusted versus unadjusted, core versus all-items, and U-3 versus U-6 are distinct definitions in this profile. Calling them variants of a common concept does not remove the distinction. Numerator and denominator roles must remain separate even when their units cancel.

Pure powers-of-ten scale are representational. An index reference level is also representational when the operation preserves the publisher-defined index series and its methodology path; changing it nevertheless requires a documented reference or conversion factor. This does not assert constant weights across all periods of the original index. Reporting an annual rate is a representation convention whose inversion requires a rule for the relevant statistical form. A GDP level convention cannot invert an annualized growth percentage.

Currency and index reference information must be retained. This candidate accepts only same-currency scale conversion and same-series re-referencing. It does not settle arbitrary currency valuation, purchasing-power conversion or chain-volume reference-year changes. Those cannot be smuggled into the scale operation.

An SDMX attribute, a graph facet or a metadata note may hold an economically material qualifier. Its storage location does not determine its semantic role.

SC03 Equivalence is scoped to a complete declared profile

The profile must state the qualifiers relevant to the requested relation or operation, their applicability, the source documentation requirements and any governed equivalence mappings. Equal raw strings alone are insufficient for independently mapped concepts. Shared values are considered equal only under the same declared meaning or an explicitly reviewed equivalence mapping.

For definition identity, all required definition fields must be supported and equal within the same profile version. A supported difference establishes distinct definitions in that profile. An unresolved required field leaves identity unestablished. Two unknown values do not compare equal. Record self-identity is still possible for an incomplete record; it is not a completeness claim.

For GDP/CPI, required fields are target, geography, coverage/population where applicable, statistical form, temporal construction, valuation where applicable, adjustment, and material method contract. For a ratio, both role definitions are required. A field can be inapplicable only with a profile-backed reason. Source publication and observation period are additionally required for substituting a particular observation, even though they are not the broad definition itself.

The curated original cases inherit only the definitions and source documentation explicitly supplied with them. Synthetic variants can assert that untouched fields are the same as their source input; that construction is not an inferred cross-provider equivalence. A successful scale example proves a transformation of one assertion, not universal completeness of a publisher's metadata.

For the included CPI operations, the fixed release's Table 1 explicitly presents the index levels as one published series path and reports its endpoint changes. The supplement supplies annual averages and their change. The requested output is a calculation on that published series, not a hypothetical constant-method historical reconstruction. The operation must not replace weights, splice another series or change the published construction. A series identifier alone, without this relationship source material, would not satisfy the condition. Detailed historical weight schedules remain outside the demonstrated mapping scope.

SC04 Keep knowledge, source provenance and acceptance separate

Absence from an extraction is not proof of absence from the source. Conflicting source material retains the alternatives and their provenance until resolved. A rule may ignore an unresolved field only if that field is explicitly irrelevant to the requested task, never merely inconvenient.

A query wildcard is a query instruction, not a measurement field value. It can broaden discovery; it cannot confirm identity or satisfy an operation precondition. An omitted query qualifier likewise does not become a default on the measurement.

For the retained World Bank example, the empty raw unit field is preserved while the title is cited as source material for a proposed currency interpretation. Mapping review and unresolved method/time details remain visible. Search can expose this candidate before it supports every comparison.

SC05 Distinguish changes to estimates from changes to construction

A value revision within a documented unchanged definition creates a new observation assertion linked to the prior release. A change in a material definition field creates a distinct definition version, even if the provider retains its series code. Where the change's role is not established, retain the method versions and return unresolved identity for tasks that depend on it.

Methodological change is not inferred from a changed value alone. Nor does every routine weight update automatically create a distinct definition. The method contract determines whether the statistical construction changed; source material must support that determination.

For MC15, the historical CPI-U and retrospectively constructed CPI-U-RS have different method contracts in this profile. Their common concept and period do not authorize replacement as the same historical measurement. The 1999 geometric mean introduction, the later reconstruction of earlier periods, ordinary data revision and pure re-referencing remain distinct events. The observed CPI-U-RS difference is not attributed exclusively to geometric means.

SC06 Preserve the separate time and source roles

Retain observation time or interval, comparison endpoints, accumulation or averaging construction, method applicability period, source publication time, dataset update time, acquisition time and mapping-review time where relevant. Do not substitute one timestamp for another.

An as-of query uses documented publication availability and a stated selection policy. A release strictly after the cutoff is ineligible. A missing publication time cannot establish eligibility for a cutoff within that day. With a latest- eligible policy, select the latest eligible assertion among the supplied releases of the requested definition, not the globally latest value. A claim about the complete historical information set additionally needs source-history coverage.

Provenance retains original publisher, source locator, release edition and mapping version. A mirror can aid discovery without becoming an independently produced measurement. Independently produced observations need not be statistically independent, semantically interchangeable or erroneous when they disagree.