Flag cross-field conflicts in location data — flag_field

Catches a class of data-entry errors the geocoder itself will silently accept: a ZIP that cannot belong to the stated state, and a stated county that disagrees with the county the coordinate actually fell in. It adds audit columns rather than changing any coordinate, so a reviewer can decide what to do.

Usage

flag_field_conflicts(
  data,
  zip = "zip_clean",
  state = "state_clean",
  stated_county = NULL,
  geocoded_county = "location_county"
)

Arguments

data: A data frame of cleaned/geocoded records.
zip: Name of the ZIP column (default "zip_clean"). Set to NULL to skip the ZIP check.
state: Name of the state column (default "state_clean").
stated_county: Optional name of a county column supplied in the input. The county check runs only when this is given.
geocoded_county: Name of the geocoded county column to compare against (default "location_county").

Value

data with three added columns: zip_state_conflict (logical, NA when indeterminate), county_conflict (logical, NA when either county is missing), and field_conflict (a "; "-joined summary such as "zip_state", "county", or "zip_state; county"; NA when clean).

Details

The ZIP check is deliberately conservative. It compares the ZIP's leading digit against the USPS regional assignment for the stated state, so it only flags a ZIP that is definitively in the wrong region (for example a "8xxxx" ZIP recorded in New Jersey). It never flags a same-region near-miss, and it stays silent when the state is unknown or the ZIP is missing, so it does not produce false positives.

The county check compares a stated county column against a geocoded county column (for example location_county from add_county_muni()), after normalising case and stripping the trailing "County"/"Parish"/"Borough".

Examples

df <- data.frame(
  zip_clean = c("07030", "85001"),   # 07 is NJ; 85 is AZ
  state_clean = c("NJ", "NJ")
)
flag_field_conflicts(df)
#>   zip_clean state_clean zip_state_conflict county_conflict field_conflict
#> 1     07030          NJ              FALSE              NA           <NA>
#> 2     85001          NJ               TRUE              NA      zip_state