Extract Unmatched Records — extract

Identify and extract records from a table that were not matched in a record linkage operation.

Usage

extract_unmatched(data, id, matches, ...)

Arguments

data: A data.frame / tibble / data.table (or db table in other backends) containing the original records.
id: Character scalar naming the ID column in data.
matches: A table of matched record pairs, containing the ID column.
...: Additional arguments passed to backend-specific methods.

Value

A subset of data containing only records whose IDs do not appear in matches.

Examples

strat <- search_strategy(
  workshop ~ normalize_text() + word_tokens(min_nchar = 3),
  block_by  = c("postcode_area", "trade"),
  threshold = 0.7
)
matches <- search_candidates(
  workshop_listings, workshop_register,
  base_id = "listing_id", target_id = "reg_no", strategy = strat
)
# The listings that found no register match, ready for a looser next pass.
leftover <- extract_unmatched(workshop_listings, "listing_id", matches)
nrow(leftover)
#> [1] 549