derivative_dates: Computes first derivative of the radiocarbon dates data

In benmarwick/au13uwgeoarchlab: Analysing and visualising geoarchaeology data

Description

This function calculates the rate of age relative to depth below the surface. It is an estimate and visualization of sedimentation rates. It uses lowess interpolation to estimate a reasonable age, give the known ages of the deposit and then computes the first order derivative at each point. It assumes you have already got the data from the Google sheet.

Usage

  derivative_dates(my_data, span = 0.75, ...)

Arguments

my_data
span	the parameter α which controls the degree of smoothing for the loess interpolation. Default is 0.75. From stats::loess

Value

The my_data data frame with one additional column, the 'deriv' column. This contains the first order derivative of the dates.

See Also

get_data and interpolate_date

Examples

my_data <- get_data()
 my_data <- derivative_dates(my_data)
 # now plot the derivative with another variable in my_data
 biplot_with_correlation(my_data, 'deriv', 'Lithic_mass_g')

benmarwick/au13uwgeoarchlab documentation built on May 12, 2019, 1:01 p.m.