README.md
In kairos: Analysis of Chronological Patterns from Archaeological Count Data

kairos

A toolkit for relative and absolute dating and analysis of chronological patterns. This package includes functions for chronological modeling and dating of archaeological assemblages from count data. It provides methods for matrix seriation. It also allows to compute time point estimates and density estimates of the occupation and duration of an archaeological site. kairos provides methods for:

Matrix seriation: seriate_rank() and seriate_average().
Testing matrix seriation results (Porčić 2013; Peeples and Schachner 2012): assess() and refine().
Mean ceramic date estimation (South 1977): mcd().
Event and accumulation date estimation (Bellanger and Husi 2012): event().
Aoristic analysis (Ratcliffe 2000): aoristic().
Chronological apportioning (Roberts et al. 2012): apportion().

tabula is a companion package to kairos that provides functions for visualization and analysis of archaeological count data.

To cite kairos in publications use:

Frerebeau N (2025). kairos: Analysis of Chronological Patterns from Archaeological Count Data. Université Bordeaux Montaigne, Pessac, France. https://doi.org/10.5281/zenodo.5653896, R package version 2.3.0, https://packages.tesselle.org/kairos/.

This package is a part of the tesselle project https://www.tesselle.org.

You can install the released version of kairos from CRAN with:

install.packages("kairos")

And the development version from Codeberg with:

# install.packages("remotes")
remotes::install_git("https://codeberg.org/tesselle/kairos")

## Load packages
library(kairos)
#> Loading required package: aion
#> Loading required package: dimensio

kairos uses aion for internal date representation. Look at vignette("aion", package = "aion") before you start.

It assumes that you keep your data tidy: each variable (type/taxa) must be saved in its own column and each observation (sample/case) must be saved in its own row.

## Data from Husi 2022
data("loire", package = "folio")
keep <- c("Anjou", "Blésois", "Orléanais", "Haut-Poitou", "Touraine")
loire <- subset(loire, area %in% keep)

## Get time range
loire_range <- loire[, c("lower", "upper")]

## Calculate aoristic sum (weights) by group
ao <- aoristic(loire_range, step = 50, weight = TRUE, groups = loire$area)

## Plot
plot(ao, col = "grey")


## Rate of change by group
set.seed(12345) # Set seed for reproductibility
ro <- roc(ao, n = 30)
plot(ro)

This package provides translations of user-facing communications, like messages, warnings and errors, and graphical elements (axis labels). The preferred language is by default taken from the locale. This can be overridden by setting of the environment variable LANGUAGE (you only need to do this once per session):

Sys.setenv(LANGUAGE = "<language code>")

Languages currently available are English (en) and French (fr).

Please note that the kairos project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.

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