# Evidence Atlas field dictionary

Version 0.2.0. JSON records are in the records array; statistics describe this release only. CSV nulls are empty cells; periods use semicolon and space. No latitude/longitude conversion is performed.

| Field | Type | Origin | Meaning |
|---|---|---|---|
| id | string | Derived | Stable ADS namespace plus source record identifier. |
| source_record_id | string | Source | Public catalogue identifier; not a CDA project reference. |
| title | string | Source | Bibliographic title, not an independently verified findings summary. |
| source_url | https URL | Source | Authoritative catalogue destination; access may be restricted. |
| doi | https URL / null | Source | DOI link where recorded; null means not supplied in this release. |
| investigation_year | integer / null | Source | Investigation year where recorded; not inferred from publication. |
| publication_year | integer | Source | Year attributed to the source report metadata. |
| organisation | string | Source | Organisation credited in metadata; not CDA client/employer evidence. |
| investigation_type | string | Source/display | Source method description conservatively normalised for display. |
| site_name | string | Source | Site description in the catalogue, not a boundary. |
| place | string | Source/display | Place name; never used to invent coordinates. |
| parish | string | Source/display | Recorded parish name. |
| district | string | Source/display | District label for discovery filters, not current consent advice. |
| county | string | Derived | Cambridgeshire; inclusion label. |
| easting | number / null | Source | British National Grid easting in metres, paired with northing. |
| northing | number / null | Source | British National Grid northing in metres; no inferred centroids. |
| coordinate_source | enum | Derived | published-grid-reference when both coordinates exist; otherwise none. |
| location_confidence | enum | Derived | published-grid-reference or unmapped. Published reference does not establish accuracy or site extent. |
| periods | string[] | Source/display | Source period terms; empty array means none recorded. CSV joins terms with semicolon and space. |
| source_system | string | Source | Catalogue/source context; ADS Library / OASIS or ADS Library. |
| source_licence | string | Source | Recorded access/reuse statement, including unconfirmed rights. Check the original source before reuse. |