14C Calibration

Calibrates radiocarbon ages.

Usage

c14_calibrate(values, errors, ...)

# S4 method for class 'numeric,numeric'
c14_calibrate(
  values,
  errors,
  curves = "intcal20",
  names = NULL,
  positions = NULL,
  reservoir_offsets = 0,
  reservoir_errors = 0,
  from = 55000,
  to = 0,
  resolution = 1,
  normalize = TRUE,
  F14C = FALSE,
  method = c("student", "normal"),
  dfs = 100,
  drop = TRUE,
  eps = 1e-06,
  verbose = getOption("ananke.verbose")
)

Arguments

values: A numeric vector giving the BP ages or F14C values to be calibrated (conventional ages).
errors: A numeric vector giving the errors associated to the values to be calibrated.
...: Currently not used.
curves: A character vector specifying the calibration curve to be used. Different curves can be specified per sample.
names: A character vector specifying the names of the samples (e.g. laboratory codes).
positions: A numeric vector giving the position values (e.g. depths) for each age.
reservoir_offsets: A numeric vector giving the offset values for any marine reservoir effect (defaults to 0; i.e. no offset).
reservoir_errors: A numeric vector giving the offset value errors for any marine reservoir effect (defaults to 0; i.e. no offset).
from: length-one numeric vector specifying the earliest data to calibrate for, in cal. BP years.
to: A length-one numeric vector specifying the latest data to calibrate for, in cal. BP years.
resolution: A length-one numeric vector specifying the temporal resolution (in years) of the calibration.
normalize: A logical scalar: should the calibration be normalized?
F14C: A logical scalar: should the calibration be carried out in F14C space? If TRUE, values must be expressed as F14C.
method: A character string specifying the distribution assumed for the 14C ages. It must be one of "student" (the default) or "normal. Only used if F14C is FALSE.
dfs: A character vector giving the degrees-of-freedom values for the student t-distribution associated with the calibration calculation. Only used if method is "student".
drop: A logical scalar: should years with zero probability be discarded? If TRUE (the default), results in a narrower time range.
eps: A length-one numeric value giving the cutoff below which calibration values will be removed.
verbose: A logical scalar: should extra information be reported (e.g. warning message for dates out of calibration range)?

Value

A CalibratedAges object.

Note

Adapted from Bchron BchronCalibrate() by Andrew Parnell and rcarbon calibrate() by Andrew Bevan and Enrico Crema.

References

Bronk Ramsey, C. (2008). Radiocarbon Dating: Revolutions in Understanding. Archaeometry, 50:249-275. doi:10.1111/j.1475-4754.2008.00394.x .

Author

N. Frerebeau

Examples

## Calibrate a single date
cal <- c14_calibrate(300, 20)
plot(cal, panel.first = graphics::grid())


## Calibrate multiple dates
cal <- c14_calibrate(
  values = c(5000, 4500),
  errors = c(45, 35),
  names = c("X", "Y")
)
plot(cal, panel.first = graphics::grid())


# \donttest{
## Out of 14C range?
out <- c14_calibrate(130, 20)
plot(out)

# }