Estimate Plans from a Block Assignment File to Voting Districts

District lines are often provided at the census block level, but analyses often occur at the voting district level. This provides a simple way to estimate the block level to the voting district level.

baf_to_vtd(baf, plan_name, GEOID = "GEOID", year = 2020)

Arguments

baf: dataframe representing a block assignment file.
plan_name: Name of the column in baf containing district assignments.
GEOID: Name of the column containing block GEOIDs, sometimes called "BLOCKID". Defaults to "GEOID".
year: Decennial vintage for the crosswalk, either 2010 or 2020.

Value

tibble with one row per voting district and the requested plan column

Details

If a voting district is split between blocks, this currently uses the most common district.

When a voting district contains blocks assigned to more than one district, the output uses the modal district assignment.

Examples

# Not guaranteed to reach download from redistrict2020.org
if (FALSE) { # \dontrun{
# download and read baf ----
url <- paste0('https://github.com/PlanScore/Redistrict2020/', 
              'raw/main/files/DE-2021-01/DE_SLDU_bef.zip')
tf <- tempfile('.zip')
utils::download.file(url, tf)
utils::unzip(tf, exdir = dirname(tf))
baf <- readr::read_csv(
  file = paste0(dirname(tf), '/DE_SLDU_bef.csv'),
  col_types = 'ci'
)
names(baf) <- c('GEOID', 'ssd_20')

# convert to vtd level ----
baf_to_vtd(baf = baf, plan_name = 'ssd_20', 'GEOID')
} # }