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Banded categories: bounds, values and what the open band costs

Source: R/bandx.R
bandx.Rd

Justice statistics are often published in bands ("1-5 days", "16 to 30", "Over 60", "Less than 1 year"). bandx() reads each label into a lower and an upper end, places a value in each band (the midpoint, an end, or the geometric mean), expands a banded frequency table into one value per unit, and shows how much a statistic of those values depends on the cap assumed for an open top band.

Usage

bandx(
  x,
  cnts = NULL,
  rule = "midpoint",
  cap = NULL,
  fac = 2,
  floor = NULL,
  clsup = TRUE,
  intsca = TRUE,
  caps = NULL,
  stat = NULL,
  drop = FALSE
)

Arguments

x

The band labels: text or a factor.

cnts

NULL, or the number of units in each band: numbers from 0.

rule

Where in a band its value sits: "midpoint", "lower", "upper" or "geometric" (the midpoint where the lower end is 0).

cap

NULL, or the end assumed for an open top band.

fac

Without cap, the open top band ends at fac times its start: one positive number.

floor

NULL, or the start assumed for an open bottom band.

clsup

TRUE when "60+" includes 60.

intsca

TRUE when the bands hold whole numbers, so that "over 60" starts at 61 and "under 10" ends at 9.

caps

NULL, or the caps at which to recompute stat (by default 12 caps from 1.05 to 20 times the open band's start).

stat

NULL, or a function of the expanded values giving one number (with cnts, and an open top band).

drop

TRUE to leave out the units of bands that cannot be read; otherwise they are an error.

Value

An object of class bandx, a list: bands, a data frame (label, lower, upper, openlo, openup, value, lo, hi the ends used); vals, the expanded values (with cnts); sens (with stat): a data frame of cap and value, and span and relspan (the span over the caps, absolute and over the median absolute value).

Details

A label is a range ("5-10", "5 to 10", "5 through 10"; any dash), a single number, or a number with a word that opens it: "60+", "60 and over", "60 or more" (from 60), "over 60", "more than 60" (from 61 for whole numbers, intsca), "10 or less" (to 10), "under 10", "less than 10", "<10" (to 9 for whole numbers). Thousands separators are dropped. With clsup = FALSE a "60+" band starts at 61. An open top band ends at cap, or at fac times its start; an open bottom band starts at floor, or at 0.

Examples

b <- c("1-5", "6-15", "16-30", "31-60", "Over 60")
n <- c(40, 25, 15, 12, 8)
r <- bandx(b, n, stat = mean)
r$bands
#>     label lower upper openlo openup value lo  hi
#> 1     1-5     1     5  FALSE  FALSE   3.0  1   5
#> 2    6-15     6    15  FALSE  FALSE  10.5  6  15
#> 3   16-30    16    30  FALSE  FALSE  23.0 16  30
#> 4   31-60    31    60  FALSE  FALSE  45.5 31  60
#> 5 Over 60    61    NA  FALSE   TRUE  91.5 61 122
r$sens
#>           cap    value
#> 1    64.05000 17.73700
#> 2    83.72753 18.52410
#> 3   109.45042 19.55302
#> 4   143.07594 20.89804
#> 5   187.03193 22.65628
#> 6   244.49214 24.95469
#> 7   319.60536 27.95921
#> 8   417.79498 31.88680
#> 9   546.15054 37.02102
#> 10  713.93968 43.73259
#> 11  933.27724 52.50609
#> 12 1220.00000 63.97500