rice (version 1.1.1)

calib.t: Comparison dates calibrated using both the t distribution (Christen and Perez 2009) and the normal distribution.

Description

Visualise how a date calibrates using the t distribution and the normal distribution.

Usage

calib.t(
  y = 2450,
  er = 50,
  t.a = 3,
  t.b = 4,
  cc = 1,
  postbomb = FALSE,
  deltaR = 0,
  deltaSTD = 0,
  as.F = FALSE,
  is.F = FALSE,
  BCAD = FALSE,
  cc.dir = c(),
  normal.col = "red",
  normal.lwd = 1.5,
  t.col = rgb(0, 0, 0, 0.25),
  t.border = rgb(0, 0, 0, 0, 0.25),
  xlim = c(),
  ylim = c()
)

Arguments

y

The reported mean of the date.

er

The reported error of the date.

t.a

Value for the t parameter a.

t.b

Value for the t parameter b.

cc

calibration curve for the radiocarbon date(s) (see the rintcal package).

postbomb

Which postbomb curve to use for negative 14C dates.

deltaR

Age offset (e.g. for marine samples).

deltaSTD

Uncertainty of the age offset (1 standard deviation).

as.F

Whether or not to calculate ages in the F14C realm. Defaults to as.F=FALSE, which uses the C14 realm.

is.F

Use this if the provided date is in the F14C realm.

BCAD

Which calendar scale to use. Defaults to cal BP, BCAD=FALSE.

cc.dir

Directory where the calibration curves for C14 dates cc are allocated. By default cc.dir=c(). Use cc.dir="." to choose current working directory. Use cc.dir="Curves/" to choose sub-folder Curves/.

normal.col

Colour of the normal curve

normal.lwd

Line width of the normal curve

t.col

Colour of the t histogram

t.border

Colour of the border of the t histogram

xlim

x axis limits

ylim

y axis limits

Author

Maarten Blaauw

Details

Radiocarbon and other dates are usually modelled using the normal distribution (red curve). The t approach (grey distribution) however allows for wider tails and thus tends to better accommodate outlying dates. This distribution requires two parameters, called 'a' and 'b'.

Examples

calib.t()