Print a compact guide to the package's data functions, their coverage, and their sources. Availability of bundled dotmaps, hexmaps, and district names is read from the package data index. Normal vote coverage counts are read from the bundled normal vote table. No maps are downloaded or loaded.
Value
Invisibly, a tibble with one row per available function and Congress,
and columns accessor, year (the Congress's starting year), congress,
and source. Availability indicates that a dataset can be requested; it
does not imply that every product uses distinct geometry for every Congress.
Details
Boundary maps cover Congresses 1 through 120 and are retrieved from Lewis's historical congressional district boundaries or the US Census. The 120th Congress combines Census boundary releases. Bundled hexmaps for 2005 through 2011 reuse a map generated for the 111th Congress (2009); those maps do not reconstruct every historical boundary change. See the individual functions for data sources and limitations.
See also
Other congressional district functions:
cd_boundaries(),
cd_dotmap(),
cd_hexmap(),
cd_mapbox(),
cd_names(),
cd_normal_vote()
Examples
cd_available()
#>
#> ── Available congressional district data ──
#>
#> • `cd_boundaries()`: 1789-2027 (Congresses 1-120); Lewis / US Census.
#> • `cd_dotmap()`: 2005-2027 (Congresses 109-120); Lewis / US Census, dodged
#> centroids.
#> • `cd_hexmap()`: 2005-2027 (Congresses 109-120); hexmap / The Downballot.
#> • `cd_names()`: 2005-2027 (Congresses 109-120); Daily Kos / The Downballot /
#> contributors.
#> • `cd_normal_vote()`: 2013-2027 (Congresses 113-120); calculated from The
#> Downballot; missing input pairs are NA.
#> Years refer to the start of a Congress, not its election year.
#> Historical hexmaps for 2005-2011 reuse the generated 2009 map.
#> Normal vote values require two presidential results on matching maps; missing
#> pairs are NA.
available <- cd_available(quiet = TRUE)
subset(available, accessor == "cd_hexmap")
#> # A tibble: 12 × 4
#> accessor year congress source
#> <chr> <int> <int> <chr>
#> 1 cd_hexmap 2005 109 Generated 2009 hexmap (reused for 2005-2011)
#> 2 cd_hexmap 2007 110 Generated 2009 hexmap (reused for 2005-2011)
#> 3 cd_hexmap 2009 111 Generated 2009 hexmap (reused for 2005-2011)
#> 4 cd_hexmap 2011 112 Generated 2009 hexmap (reused for 2005-2011)
#> 5 cd_hexmap 2013 113 The Downballot
#> 6 cd_hexmap 2015 114 The Downballot
#> 7 cd_hexmap 2017 115 The Downballot
#> 8 cd_hexmap 2019 116 The Downballot
#> 9 cd_hexmap 2021 117 The Downballot
#> 10 cd_hexmap 2023 118 The Downballot
#> 11 cd_hexmap 2025 119 The Downballot
#> 12 cd_hexmap 2027 120 The Downballot