# common masters

Header-only bootstrap files for shared master data.
Do not add run-specific temporary mappings here; keep temporary local overrides
outside the public dictionary namespace.

Auxiliary reference dictionaries may also live here when they are reused by
multiple pipeline stages.

Current auxiliary reference:
- `scope_master.csv`
  - role: normalized scope taxonomy for `national / nationwide_constituency / region / prefecture / municipality / special`
  - current decision basis: keep `jurisdiction_scope` stable while normalizing ops prose and region execution layers
- `scope_alias.csv`
  - role: normalize shorthand labels such as `全国区`, `県`, and `市町村` to canonical scope ids
  - scope: dictionary / ops prose normalization
- `region_block_master.csv`
  - role: normalized region block entities used by the current project execution taxonomy
  - current note: this is the project block taxonomy, not a universal Japan region standard
  - current note 2: the ops-region canonical label is `中国地方`; official election labels such as `pr_block=中国` remain separate
- `region_block_alias.csv`
  - role: normalize region-layer shorthand such as `中国` and `近畿地方` to canonical `region_block_id`
  - scope: ops region taxonomy only; not a country classifier and not a replacement for official election block labels
- `prefecture_region_map.csv`
  - role: prefecture-to-region mapping for the current project execution taxonomy
- `gazetteer_japan_2021.csv`
  - source evidence: official Gazetteer reference PDF used during dictionary preparation
  - role: municipality romanization reference
  - current status: auxiliary only; not merged into `area_master.csv`
  - current decision basis: public gazetteer coverage review note
- `municipality_romanization_overrides.csv`
  - role: fallback romanization overrides for names not covered by Gazetteer exact match
  - scope: L3 review/public deliverables only
  - current status: auxiliary only; not merged into `area_master.csv`
- `municipality_transition_event.csv`
  - role: official municipality transition events for mergers, incorporations, city promotions, and ward reorganizations
  - source evidence: official e-Stat `廃置分合等情報` detail pages
  - scope: continuity helper for selector-oriented longitudinal work such as `municipality-series`
- `municipality_transition_link.csv`
  - role: machine-readable predecessor -> successor municipality links derived from official transition pages
  - source evidence: official e-Stat `廃置分合等情報` detail pages plus deterministic resolution against `area_master.csv`
  - scope: no inferred continuity; unresolved official ambiguity stays blank and explicit

Municipality and prefecture masters are built from official e-Stat CSV inputs in
the internal toolchain and published here after review.