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geocoding_summary.txt

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+Geocoding Summary
+
+Output file:
+US_DC_Sample_geocoded.csv
+
+What was added:
+- longitude
+- latitude
+- geocode_source
+- geocode_precision
+- geocode_status
+- geocode_match_address
+- Census audit fields
+- Nominatim/OpenStreetMap audit fields
+
+Results:
+- 249 total records
+- 204 records matched through the U.S. Census Geocoder
+- 45 records used city-level fallback coordinates from Nominatim/OpenStreetMap
+- 0 records are missing coordinates
+- Final CSV has 38 columns with consistent row width
+
+Precision notes:
+- Census matches are marked geocode_precision=address_range.
+- Census coordinates are interpolated address-range coordinates, not guaranteed rooftop or building-centroid coordinates.
+- Nominatim fallback records are marked geocode_precision=city.
+- City-level fallback coordinates should not be treated as facility-level locations.
+
+Status values:
+- census_match: Census returned a usable address match.
+- census_no_match_city_fallback: Census did not match the submitted street address, so city-level fallback coordinates were used.
+- census_tie_city_fallback: Census returned a tie, so city-level fallback coordinates were used instead of selecting one ambiguous address.
+- no_street_city_fallback: No usable street address was available, so city-level fallback coordinates were used.
+
+Repair note:
+Before geocoding, 3 records were repaired where a street address existed in source_address but had not been parsed into street_address.
+
+Supporting audit files:
+- census_address_results.csv
+- nominatim_city_cache.csv
+- US_DC_Sample_geocoding_base.csv
+- census_address_input.csv
+
+Source documentation:
+- U.S. Census Geocoder API:
+  https://geocoding.geo.census.gov/geocoder/Geocoding_Services_API.html
+- Nominatim/OpenStreetMap usage policy:
+  https://operations.osmfoundation.org/policies/nominatim/
+
+Attribution note:
+If the Nominatim/OpenStreetMap fallback coordinates are published or distributed, include appropriate OpenStreetMap attribution.