Files
uscogdata/R/peers.R
T
jared 81fd1a5279 feat: refuse expenditure_concept = total in the cross-government verbs
Owner ruling R1. Combining Census Total across governments counts
intergovernmental transfers twice, and these results land in Tableau where a
warning would be invisible -- so this is a hard error whose message names the
fix and the reason.
2026-07-27 10:14:16 -04:00

261 lines
9.9 KiB
R

# R/peers.R
#' Find peer governments by similarity criteria
#'
#' Selects peer governments by combinations of government type, state, and
#' population range at a chosen `year`. Peers are ordered by `|log(pop_ratio)|`
#' ascending (closest to the target's population first).
#'
#' @param target_govid Character scalar — `canonical_govid` of the target.
#' @param year Integer scalar. Cohort vintage. When `NULL` (default), uses the
#' most recent year for which the target has an observed population in
#' `gov_population_yearly`.
#' @param same_type If `TRUE` (default) restrict peers to the target's
#' `govs_type`.
#' @param same_state If `TRUE` restrict peers to the target's `fips_state`.
#' Default `FALSE`.
#' @param pop_range Length-2 numeric vector giving lower/upper bounds.
#' @param is_ratio If `TRUE` (default) `pop_range` is multiplied by the
#' target's population at `year` to produce absolute bounds. If `FALSE`,
#' `pop_range` is interpreted as absolute population counts.
#' @param max_peers Integer cap on the number of peers returned.
#' @return Tibble with columns `canonical_govid`, `gov_name`, `fips_state`,
#' `population`, `pop_ratio`, `rank`. The cohort year is attached as
#' `attr(x, "cohort_year")`.
#' @export
cog_find_peers <- function(target_govid,
year = NULL,
same_type = TRUE,
same_state = FALSE,
pop_range = c(0.7, 1.3),
is_ratio = TRUE,
max_peers = 10L) {
if (!is.character(target_govid) || length(target_govid) != 1L) {
cli::cli_abort("`target_govid` must be a length-1 character string.")
}
if (!is.numeric(pop_range) || length(pop_range) != 2L ||
pop_range[1] >= pop_range[2]) {
cli::cli_abort("`pop_range` must be a length-2 numeric with lo < hi.")
}
if (!is.null(year) &&
(!(is.numeric(year) || is.integer(year)) || length(year) != 1L)) {
cli::cli_abort("`year` must be NULL or a length-1 integer.")
}
con <- .ensure_session()
# Confirm target exists in the xwalk and pull govs_type / fips_state.
meta_sql <- sprintf(
"SELECT canonical_govid, gov_name, govs_type, fips_state
FROM canonical_fips_xwalk
WHERE canonical_govid = %s",
.sql_lit_chr(target_govid)
)
meta <- DBI::dbGetQuery(con, meta_sql)
if (nrow(meta) == 0L) {
cli::cli_abort(c(
"govid {target_govid} not found in corpus.",
i = "v0.1 covers types 0-3 only (state/county/city/township); see vignette('coverage-scope')."
))
}
cohort_year <- .resolve_cohort_year(con, target_govid, year)
pop_sql <- sprintf(
"SELECT population FROM gov_population_yearly
WHERE canonical_govid = %s AND year = %d",
.sql_lit_chr(target_govid), as.integer(cohort_year)
)
target_pop <- DBI::dbGetQuery(con, pop_sql)$population
if (length(target_pop) == 0L || is.na(target_pop) || target_pop <= 0) {
cli::cli_abort(c(
"Target {target_govid} has no observed population in {cohort_year}.",
i = "Use a year for which population is observed; see gov_population_yearly."
))
}
if (isTRUE(is_ratio)) {
lo <- target_pop * pop_range[1]
hi <- target_pop * pop_range[2]
} else {
lo <- pop_range[1]; hi <- pop_range[2]
}
preds <- c(
sprintf("p.canonical_govid != %s", .sql_lit_chr(target_govid)),
sprintf("p.year = %d", as.integer(cohort_year)),
sprintf("p.population BETWEEN %.6f AND %.6f", lo, hi)
)
if (isTRUE(same_type)) preds <- c(preds, sprintf("x.govs_type = %d", meta$govs_type))
if (isTRUE(same_state)) preds <- c(preds, sprintf("x.fips_state = %s", .sql_lit_chr(meta$fips_state)))
peers_sql <- sprintf(
"SELECT p.canonical_govid, x.gov_name, x.fips_state, p.population,
p.population / %.6f AS pop_ratio
FROM gov_population_yearly p
JOIN canonical_fips_xwalk x USING (canonical_govid)
WHERE %s
ORDER BY ABS(LN(CAST(p.population AS DOUBLE) / %.6f))
LIMIT %d",
target_pop,
paste(preds, collapse = " AND "),
target_pop,
as.integer(max_peers)
)
peers <- tibble::as_tibble(DBI::dbGetQuery(con, peers_sql))
peers$rank <- if (nrow(peers) > 0L) seq_len(nrow(peers)) else integer(0)
attr(peers, "cohort_year") <- as.integer(cohort_year)
attr(peers, "pop_range") <- as.numeric(pop_range)
attr(peers, "is_ratio") <- isTRUE(is_ratio)
peers
}
#' @noRd
.resolve_cohort_year <- function(con, target_govid, year) {
if (!is.null(year)) return(as.integer(year))
sql <- sprintf(
"SELECT MAX(year) AS y FROM gov_population_yearly
WHERE canonical_govid = %s",
.sql_lit_chr(target_govid)
)
y <- DBI::dbGetQuery(con, sql)$y
if (length(y) == 0L || is.na(y)) {
cli::cli_abort(
"Target {target_govid} has no observed population in any year."
)
}
as.integer(y)
}
#' Compare a target government against a peer set
#'
#' Pulls spending for the target plus a peer set (either a
#' [cog_find_peers()] result or a character vector of `canonical_govid`) and
#' appends peer-distribution summary rows (`summary_p25`, `summary_p50`,
#' `summary_p75`) so the result can be faceted by `role` in a single ggplot
#' call.
#'
#' @param target_govid Character scalar.
#' @param peers A tibble from [cog_find_peers()] or a character vector of
#' `canonical_govid`s.
#' @param category Character scalar or vector.
#' @param years Integer vector.
#' @param per_capita Default `TRUE` — peer compare usually normalizes by
#' population.
#' @param adjust_to_year Integer base year for CPI-U conversion or `NULL`.
#' @param expenditure_concept `"direct"` (default) or `"total"`. Currently only
#' `"direct"` is accepted; the `"total"` option exists in [cog_spending()] for
#' single-government queries but cannot be used here because combining Total
#' across peer sets counts intergovernmental transfers twice.
#' @return Tibble matching [cog_spending()]'s columns, plus a `role`
#' column taking values `"target"`, `"peer"`, `"summary_p25"`,
#' `"summary_p50"`, or `"summary_p75"`, `target_rank` (target's rank
#' among target+peers at `max(years)`, NA for other rows), and
#' `cohort_year` (the year used to build the peer cohort, read from
#' `attr(peers, "cohort_year")`; `NA` when `peers` was a bare character
#' vector). Provenance reports `verb = "cog_peer_compare"`, `peer_count`,
#' `cohort_year`, and `cohort_govids`.
#' @export
cog_peer_compare <- function(target_govid, peers, category, years,
per_capita = TRUE, adjust_to_year = NULL,
expenditure_concept = c("direct", "total")) {
call <- match.call()
expenditure_concept <- match.arg(expenditure_concept)
if (identical(expenditure_concept, "total")) {
.abort_concept_not_aggregatable("cog_peer_compare")
}
if (!is.character(target_govid) || length(target_govid) != 1L) {
cli::cli_abort("`target_govid` must be a length-1 character string.")
}
cohort_year <- if (is.data.frame(peers)) {
ay <- attr(peers, "cohort_year")
if (is.null(ay)) NA_integer_ else as.integer(ay)
} else {
NA_integer_
}
pop_range <- if (is.data.frame(peers)) attr(peers, "pop_range") else NULL
is_ratio <- if (is.data.frame(peers)) attr(peers, "is_ratio") else NULL
peer_govids <- if (is.data.frame(peers)) {
as.character(peers$canonical_govid)
} else {
as.character(peers)
}
peer_govids <- peer_govids[!is.na(peer_govids) & nzchar(peer_govids)]
all_govids <- unique(c(target_govid, peer_govids))
r <- cog_spending(all_govids, years, category, per_capita, adjust_to_year)
r$role <- ifelse(r$canonical_govid == target_govid, "target", "peer")
value_col <- .peer_value_col(per_capita, adjust_to_year)
summary_rows <- .peer_summary_rows(r, value_col)
out <- dplyr::bind_rows(r, summary_rows)
rank_val <- .peer_target_rank(r, target_govid, years, value_col)
out$target_rank <- ifelse(out$role == "target", rank_val, NA_integer_)
out$cohort_year <- cohort_year
prov <- attr(r, "provenance") %||% list()
prov$verb <- "cog_peer_compare"
prov$call <- paste(deparse(call), collapse = " ")
prov$peer_count <- length(peer_govids)
prov$cohort_year <- cohort_year
prov$cohort_govids <- peer_govids
prov$pop_range <- pop_range
prov$is_ratio <- is_ratio
prov$target <- list(
canonical_govid = target_govid,
gov_name = unique(r$gov_name[r$role == "target"])
)
attr(out, "provenance") <- prov
out
}
#' @noRd
.peer_value_col <- function(per_capita, adjust_to_year) {
if (!is.null(adjust_to_year)) {
if (isTRUE(per_capita)) "amt_per_capita_real" else "amt_real"
} else {
if (isTRUE(per_capita)) "amt_per_capita_nominal" else "amt_nominal"
}
}
#' @noRd
.peer_summary_rows <- function(r, value_col) {
peer_rows <- r[r$role == "peer", , drop = FALSE]
if (nrow(peer_rows) == 0L) {
return(r[integer(0), , drop = FALSE])
}
s <- peer_rows |>
dplyr::group_by(.data$year, .data$spend_subtype, .data$category) |>
dplyr::reframe(
q = c("p25", "p50", "p75"),
value = stats::quantile(
.data[[value_col]], c(0.25, 0.50, 0.75), na.rm = TRUE
)
)
s$role <- paste0("summary_", s$q)
s$gov_name <- dplyr::case_when(
s$q == "p25" ~ "Peer P25",
s$q == "p50" ~ "Peer median",
s$q == "p75" ~ "Peer P75",
TRUE ~ NA_character_
)
s$canonical_govid <- NA_character_
out <- s[, c("year", "canonical_govid", "gov_name",
"spend_subtype", "category", "role")]
out[[value_col]] <- s$value
out
}
#' @noRd
.peer_target_rank <- function(r, target_govid, years, value_col) {
if (nrow(r) == 0L) return(NA_integer_)
latest <- max(as.integer(years))
latest_rows <- r[r$year == latest &
r$role %in% c("target", "peer"), , drop = FALSE]
if (nrow(latest_rows) == 0L) return(NA_integer_)
ranked <- dplyr::arrange(latest_rows, dplyr::desc(.data[[value_col]]))
tr <- which(ranked$canonical_govid == target_govid)[1]
if (length(tr) == 0L || is.na(tr)) NA_integer_ else as.integer(tr)
}