Skip to contents

Map data between editions using correspondence tables from the ABS.

Usage

map_data_with_correspondence(
  .data = NULL,
  codes,
  values,
  groups = NULL,
  from_area = NULL,
  from_year = NULL,
  from_geo = NULL,
  to_area = NULL,
  to_year = NULL,
  to_geo = NULL,
  correspondence_tbl = NULL,
  mb_geo = get_mb21_pop(),
  value_type = c("units", "aggs"),
  export_fname = NULL,
  round_values = FALSE,
  seed = NULL,
  quiet = getOption("hpa.spatial.quiet", FALSE)
)

Arguments

.data

A data.frame(-like) object. Can be passed if codes, values or groups are passed by reference (like in dplyr::mutate()).

codes

Codes representing locations relevant to the from_area. SA1 or SA2, for example.

values

Values associated with codes to be allocated to newly mapped codes.

groups

Values associated with codes/values specifying a grouping structure. For example, if there are codes/values for several age groups, then groups will be the grouping variable for the age group associated with the code and value of the same position. Defaults to NULL (no grouping).

from_area

The area you want to correspond FROM (ie the areas your data are currently in). For example: "sa1", "sa2, "sa3", "sa4".

from_year

The year you want to correspond FROM. For example: 2011, 2016.

from_geo

The FROM polygon geography. Helpful if it is not available using from_year and from_area in get_polygon.

to_area

The area you want to correspond TO (ie the areas you want your data to be in).

to_year

The year you want to correspond TO.

to_geo

The TO polygon geography. Helpful if it is not available using to_year and to_area in get_polygon.

correspondence_tbl

A correspondence table to be used to map values between code sets. It should contain 3 columns: (1) code set FROM which values are being mapped, (2) code set TO which values are being mapped, and (3) a column named "ratio" containing the proportion/probability of the value(s) being mapped between the from- and to- code pair (row). Defaults to NULL, in which case it will attempt to get the correspondence table from the ABS and, if not available, it will create a correspondence table based on the overlap of the shapes and the residential population in the intersection (uses mb_geo argument).

mb_geo

An {sf} POINT object where the points are the centroids of a small area (intended to be mesh blocks but can be any other space that's small enough to be useful. Should also include a column, Person, with the population within that area. Defaults to use Mesh Blocks (2021) and with 2021 census data. See get_mb21_pop().

value_type

Whether the data are unit level or aggregate level data. Unit level data is randomly allocated to new locations based on proportions in the correspondence table, aggregate data is dispersed based on the proportion across the (potentially multiple) mapped codes.

export_fname

The file name for the saved correspondence table file (applicable if from_geo) and to_geo are used instead of areas and years).

round_values

Whether or not to round the resulting mapped values to be whole numbers (maybe be useful when mapping count, aggregate values which may otherwise return decimal values in the mapped areas).

seed

A random seed (integer). May be useful for ensuring mappings of unit level data are reproducible (as these use the mapping probabilities for randomly allocating observations to the new geographies and may be different between runs with the same data/inputs).

quiet

whether to be quiet about warnings. Set package level quiet-ness with options(hpa.spatial.quiet = TRUE).

Value

A data.frame.

Examples

map_data_with_correspondence(
  codes = c(107011130, 107041149),
  values = c(10, 10),
  from_area = "sa2",
  from_year = 2011,
  to_area = "sa2",
  to_year = 2016,
  value_type = "units"
)
#> # A tibble: 2 × 2
#>   sa2_maincode_2016 values
#>   <chr>              <dbl>
#> 1 107011545             10
#> 2 107041548             10
map_data_with_correspondence(
  codes = c(107011130, 107041149),
  values = c(10, 10),
  from_area = "sa2",
  from_year = 2011,
  to_area = "sa2",
  to_year = 2016,
  value_type = "aggs"
)
#> # A tibble: 5 × 2
#>   sa2_maincode_2016 values
#>   <chr>              <dbl>
#> 1 107011545           4.82
#> 2 107011546           3.62
#> 3 107011547           1.57
#> 4 107041548           4.49
#> 5 107041549           5.51