geoalgeria data notices

Package code is licensed under the MIT License in LICENSE, and so is the
compilation of wilayas, dairas, communes, their bilingual names, postal codes and
administrative codes. Five parts of the data are not: four derived from
OpenStreetMap, and the mirrored postal data under data/poste/.

The four parts derived from OpenStreetMap are made available under the Open
Database License (ODbL) 1.0 instead. Attribution:
(c) OpenStreetMap contributors
https://opendatacommons.org/licenses/odbl/1-0/
https://www.openstreetmap.org/copyright

1. Wilaya boundary polygons

   data/geojson/wilaya-boundaries.geojson, 69 features, derived from
   OpenStreetMap `admin_level=4` relations, retrieved 2026-06-21, simplified with
   mapshaper. Provenance, including the one deliberate departure from upstream
   OpenStreetMap, is in data/geojson/wilaya-boundaries.metadata.json.

2. Commune centre coordinates

   323 of the 1,541 commune `latitude` / `longitude` values, each taken from that
   commune's own OpenStreetMap `admin_level=8` relation:

   - 56 corrected on 2026-09-27 from the relation's `admin_centre` node, Overpass
     `timestamp_osm_base` 2026-09-27T11:03:52Z. Every row, with its OSM relation
     id, `admin_centre` node id and `ref:ONS`, is listed in
     research/_commune-centres/corrections-2026-09-27.json in the repository, and
     summarised in data/geojson/communes.metadata.json.
   - 189 corrected on 2026-09-29 from the same node, Overpass
     `timestamp_osm_base` 2026-09-29T12:54:47Z, after every one of the 1,541
     centres was compared with its relation's `admin_centre` and tested against
     the relation's own unsimplified boundary. Every row, with the same ids and
     the four containment verdicts that decided it, is listed in
     research/_commune-centres/corrections-2026-09-29.json.
   - 5 corrected on 2026-10-01 from the same node, same Overpass
     `timestamp_osm_base` 2026-09-29T12:54:47Z, each node re-read from the
     OpenStreetMap node API on 2026-10-01: the wilaya capital communes Biskra
     (701), El Kantara (717), Constantine (2501), El Bayadh (3201) and
     Beni-Abbes (5201), each 3 to 6 km from the seat of the town it is the
     chef-lieu of. Every row, with the same ids and the independent claims that
     decided it, is listed in
     research/_commune-centres/corrections-2026-10-01.json. One of the five,
     Beni-Abbes, additionally carries a reading the project owner took from a
     proprietary map; it is recorded there as a confirmation of this node, which
     it agrees with to 268 m, and never as the published value, so the ODbL
     covers this coordinate exactly as it covers the other four.
   - 68 corrected on 2026-10-01 from the same node, same Overpass
     `timestamp_osm_base` 2026-09-29T12:54:47Z, by the coordinate review engine:
     each of the 136 centres more than 3 km from its seat, or with no seat, was
     weighed against the open sources that state where its town is, and a value
     was written only where at least three of them agree, or two including the
     median of the exact records inside the commune's own outline, with nothing
     voting for a different answer and the value inside that outline. Every row,
     with its Candidates and the Votes that decided it, is listed in
     research/_commune-centres/corrections-2026-10-01b.json; the 67 the engine
     did not settle are in research/_commune-centres/review-queue-2026-10-01.json
     and keep the coordinates they already had. The rules are
     docs/adr/0001-coordinate-review-by-independent-votes.md. No reading from a
     proprietary map decided any of the 68.
   - 5 corrected in version 2.1.0 from the relation centroid, matched on the
     relation's `ref` tag: Belarbi (2242), El Hamdania (2616), Ouled Bouachra
     (2627), Deux Bassins (2653) and Makhda (2915). See CHANGELOG.md, 2.1.0.
     El Euch (3427) was a sixth until 2026-10-01, when the coordinate review moved
     it 9.7 km off that centroid onto its own `admin_centre` node, so it is counted
     with the node corrections above and not here. Si Mahdjoub (2644) and El Achir (3407) are NOT in this
     set: each kept the placeholder point it shared with its neighbour, still
     byte-identical to its pre-2.1.0 value, so no OpenStreetMap value was ever
     written to either and no ODbL claim is made over them.

   A commune centre is one value repeated across representations, so the ODbL
   covers these 323 coordinates wherever they appear: data/algeria.json,
   data/communes_w1_w23.json, data/communes_w24_w48.json,
   data/communes_w49_w69.json, data/csv/communes.csv,
   data/geojson/communes.geojson and data/sql/full.sql.

   The other 1,218 commune coordinates are not OpenStreetMap-derived and no ODbL
   claim is made over them.

3. Wilaya capital points

   A wilaya's latitude / longitude is the centre of its capital commune
   (capital_commune_code), the same value and not a second reading of it, so it
   carries whatever terms that commune centre carries. 6 of the 69 wilaya capital
   points are therefore among the OpenStreetMap-derived coordinates above and are
   ODbL 1.0, (c) OpenStreetMap contributors: wilayas 7 (Biskra, commune 701),
   16 (Alger Centre, 1601), 25 (Constantine, 2501), 32 (El Bayadh, 3201),
   52 (Beni-Abbes, 5201) and 61 (El Kantara, 717). They appear in
   data/algeria.json, data/csv/wilayas.csv, data/sql/full.sql,
   data/geojson/wilayas.geojson and algeria.geojson.

   The other 63 wilaya capital points are the centres of communes with no
   recorded source, are not OpenStreetMap-derived and no ODbL claim is made over
   them.

4. OpenStreetMap relation ids and Wikidata items

   The osm_relation_id and wikidata values on the commune and wilaya records, read
   off the Overpass capture of the Algerian administrative relations whose
   timestamp_osm_base is 2026-09-29T12:54:47Z
   (research/_commune-centres/osm-2026-09-29/admin-relations.json in the
   repository):

   - 1,537 of the 1,541 communes carry the id of their own admin_level=8 relation,
     and 1,536 of them carry the wikidata item that relation is tagged with. Souk
     Oufella (630), Bir Touta (1634), Collo (2110) and Dhayet Bendhahoua (4703)
     carry null in both fields, because the capture holds no relation for them, and
     Ain-Defla (4401) carries its relation with a null item, because the relation has
     no wikidata tag.
   - All 69 wilayas carry the id of their own admin_level=4 relation and that
     relation's wikidata item.

   The linkage is the one scripts/audit-commune-centres.mjs decided and
   research/_commune-centres/osm-seat-reference.json records: a commune relation is
   joined on its ref:ONS tag, then on a pre-2019-reform ONS code resolved inside the
   mother wilaya's carved-out communes, then on six reviewed per-relation pins; a
   wilaya relation is joined on its ref tag. No record is linked by a name alone.
   Coverage and the five records above are in data/osm-links.metadata.json.

   These values are carried by data/algeria.json, data/communes_w1_w23.json,
   data/communes_w24_w48.json, data/communes_w49_w69.json and data/wilayas.json. The
   CSV, GeoJSON and SQL representations do not carry them. The Wikidata items are
   OpenStreetMap tag values, not the result of a query against Wikidata, so the ODbL
   covers them here as it covers the relation ids.

5. Mirrored postal data

   data/poste/ (postoffices.json, atms.json, their CSV and GeoJSON
   representations and their metadata.json) is a generated mirror of
   @geoalgeria/poste, whose source is Algérie Poste's BaridiMap portal
   (https://baridimap.poste.dz), retrieved 2026-06-08. Terms, exactly as
   @geoalgeria/poste states them:

   Data © Algérie Poste; redistributed for reference

   The underlying data is © Algérie Poste, redistributed for reference and to
   power GeoAlgeria (https://geoalgeria.com). It is not offered under the MIT
   License, and no open licence is claimed over it. The post office and ATM
   postal codes, commune codes and wilaya codes carried alongside it are part of
   the MIT compilation above.

Database rights and share-alike obligations may apply to redistributed derived
databases. This notice does not replace any applicable licence text or source
terms.
