estimateDataDomain: Estimates the calendar date domain of a 14C dataset

In UCL/ADMUR: Ancient Demographic Modelling Using Radiocarbon

Estimates the calendar date domain of a 14C dataset

Description

Estimates the approximate date range of a 14C dataset, in calendar time

Usage

estimateDataDomain(data, calcurve)

Arguments

data	A dataframe of 14C dates. Requires 'age' and 'sd', and at least one of 'site' and 'phase'. Optional 'datingType' to include '14C' and anything else.
calcurve	A calibration curve object. Choose from intcal20 (default), shcal20, intcal13 or shcal13.

Details

Since dates are derived from normal (or log normal) distributions, they have no absolute cut off point. However, in practice the tail of a PDF rapidly becomes vanishingly small, so a date range can be estimated using an arbitrarily large interval (0.000001 to 0.999999) of the cumulative distribution.

In practice however, the date range chosen to model should not be selected using this function, but carefully chosen to ensure the date range is fairly represented by the data set.

Therefore this function should only be used to select a date range to model if simulating a tiny sample size, to ensure the modelled range does not exceed the date domain of the data.

Value

Returns a vector of two calendar dates BP.

Examples

# a single date within the 14C range 5000 to 10000
data <- data.frame(
		age = round(runif(1,5000,10000)), 
		sd = 3,
		datingType = '14C'
		)
estimateDataDomain(data, calcurve=intcal20)

# 50 dates within the 14C range 5000 to 10000
data <- data.frame(
		age = round(runif(50,5000,10000)), 
		sd = rep(50,50),
		datingType = rep('14C',50)
		)
estimateDataDomain(data, calcurve=intcal20)

UCL/ADMUR documentation built on Sept. 14, 2023, 11:41 a.m.