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Estimates the u probabilities (the probability of observing each comparison level given that the records do not match) by randomly sampling record pairs. Most random pairs are non-matches, so the observed level frequencies approximate the u distribution.

Usage

il_estimate_u(
  model,
  max_pairs = 1e+06,
  min_count_per_level = NULL,
  chunk_size = NULL,
  profile_sql = FALSE
)

Arguments

model

An il_model object (piped in).

max_pairs

Maximum number of random pairs to sample. Defaults to 1e6.

min_count_per_level

Optional integer. When set, chunked estimation stops once every comparison level has been observed at least this many times, or once max_pairs has been sampled.

chunk_size

Optional integer number of pairs to score per chunk. When set, u estimation accumulates gamma counts across chunks instead of using one aggregate query.

profile_sql

Logical. If TRUE, store lightweight SQL timing metadata in model$params$sql_profile.

Value

An updated il_model with estimated u parameters.

Examples

df <- data.frame(
  unique_id = 1:20,
  first_name = c(
    'John', 'Jon', 'Jane', 'Jane', 'Bob',
    'Bobby', 'Alice', 'Alicia', 'Tom', 'Thomas',
    'John', 'Jon', 'Jane', 'Janet', 'Bob',
    'Robert', 'Alice', 'Alison', 'Tom', 'Tomas'
  ),
  surname = c(
    'Smith', 'Smith', 'Doe', 'Doe', 'Jones',
    'Jones', 'Brown', 'Brown', 'White', 'White',
    'Smith', 'Smyth', 'Doe', 'Doe', 'Jones',
    'Jones', 'Brown', 'Browne', 'White', 'White'
  ),
  dob = c(
    '1990-01-01', '1990-01-01', '1985-06-15', '1985-06-15',
    '2000-12-01', '2000-12-01', '1975-03-22', '1975-03-22',
    '1988-07-04', '1988-07-04', '1990-01-01', '1990-01-02',
    '1985-06-15', '1985-06-16', '2000-12-01', '2000-12-02',
    '1975-03-22', '1975-03-23', '1988-07-04', '1988-07-05'
  ),
  city = c(
    'London', 'London', 'Paris', 'Paris', 'Berlin',
    'Berlin', 'Rome', 'Rome', 'Madrid', 'Madrid',
    'London', 'London', 'Paris', 'Paris', 'Berlin',
    'Berlin', 'Rome', 'Rome', 'Madrid', 'Madrid'
  ),
  email = c(
    'john@example.com', 'jon@example.com', 'jane@example.com',
    'jane@example.com', 'bob@example.com', 'bobby@example.com',
    'alice@example.com', 'alicia@example.com', 'tom@example.com',
    'thomas@example.com', 'john@example.com', 'jon@example.com',
    'jane@example.com', 'janet@example.com', 'bob@example.com',
    'robert@example.com', 'alice@example.com', 'alison@example.com',
    'tom@example.com', 'tomas@example.com'
  )
)
con <- DBI::dbConnect(duckdb::duckdb())
spec <- il_spec() |>
  il_compare(first_name, cl_jaro_winkler(0.9, 0.7)) |>
  il_compare(surname, cl_jaro_winkler(0.9, 0.7)) |>
  il_compare(dob, cl_exact()) |>
  il_block_on(surname) |>
  il_block_on(first_name)
model <- il_model(df, spec = spec, con = con)

model <- il_estimate_u(model)
DBI::dbDisconnect(con, shutdown = TRUE)