Get NHGIS Geographic Crosswalk
get_nhgis_crosswalk.RdRetrieves a geographic crosswalk from the IPUMS NHGIS API based on user-specified
source and target geographies and years. Use list_nhgis_crosswalks() to view valid
parameter combinations.
Usage
get_nhgis_crosswalk(
source_year,
source_geography,
target_year,
target_geography,
download_directory,
use_cache = FALSE,
api_key = NULL
)Arguments
- source_year
Character or numeric. Year of the source geography one of c(1990, 2000, 2010, 2020).
- source_geography
Character. Source geography name. One of c("block", "block group", "tract").
- target_year
Character or numeric. Year of the target geography, one of c(1990, 2000, 2010, 2020).
- target_geography
Character. Target geography name. One of c("block", "block group", "tract", "county").
- download_directory
File path. Where to download the crosswalk to.
- use_cache
FALSE by default. If TRUE, read in an already-downloaded crosswalk stored in the
download_directory, if such a file exists.- api_key
Character. NULL by default, in which case the function looks for an
IPUMS_API_KEYenvironment variable.
Value
A data frame containing the crosswalk between the specified geographies.
#' @return A dataframe representing the requested Geocorr22 crosswalk for all 51 states and Puerto Rico. Depending on the desired geographies, some fields may not be included.
- source_geoid
A unique identifier for the source geography
- target_geoid
A unique identifier for the target geography
- source_geography_name
The name of the source geography
- target_geography_name
The name of the target geography
- source_year
The year of the source geography
- target_year
The year of the target geography
- allocation_factor_source_to_target
The weight to interpolate values from the source geography to the target geography
- weighting_factor
The attribute used to calculate allocation factors