Clustering of calibrated radiocarbon dates

Overview

A python implementation of the method of clustering radiocarbon dates in order to determine whether they represent separate events, or phases in time. For an overview of the method see:

Demján, P., & Pavúk, P. (2021). CLUSTERING OF CALIBRATED RADIOCARBON DATES: SITE-SPECIFIC CHRONOLOGICAL SEQUENCES IDENTIFIED BY DENSE RADIOCARBON SAMPLING. Radiocarbon, 63(2), 429-438. doi:10.1017/RDC.2020.129

How to run

Find optimal number of clusters:

python process.py [dates file].txt [sequence / contiguous / overlapping]

Find a specified number of clusters:

python process_n.py [dates file].txt [clusters_n] [sequence / contiguous / overlapping]

[sequence / contiguous / overlapping] specifies the type of OxCal phasing model generated. If no model is specified, sequence is used by default.

Input radiocarbon dates have to be supplied in the text file [dates file].txt where each row represents a date in the format:

[Lab Code], [14C Age], [Uncertainty]

(see example data in dates_2_events.txt)

The script generates a graph of Silhouette and p-value and an OxCal model file stored as:

output\[dates file].pdf
output\[dates file].oxcal

Example data representing two events are included in dates_2_events.txt. To run with sample data use e.g.:

python process.py dates_2_events.txt sequence

Requirements

Running the script requires Python 3.6

Dependencies

The script requires the following libraries to be installed:

• NumPy
• SciPy
• scikit-learn

pip install numpy
pip install scipy
pip install scikit-learn

Author:

Peter Demján peter.demjan@gmail.com

Institute of Archaeology of the Czech Academy of Sciences, Prague, v.v.i.

Acknowledgements:

Development of this script was supported by OP RDE, MEYS, under the project "Ultra-trace isotope research in social and environmental studies using accelerator mass spectrometry", Reg. No. CZ.02.1.01/0.0/0.0/16_019/0000728.

Uses atmospheric data intcal13.14c from:

Reimer PJ, Bard E, Bayliss A, Beck JW, Blackwell PG, Bronk Ramsey C, Buck CE, Cheng H, Edwards RL, Friedrich M, Grootes PM, Guilderson TP, Haflidason H, Hajdas I, Hatté C, Heaton TJ, Hogg AG, Hughen KA, Kaiser KF, Kromer B, Manning SW, Niu M, Reimer RW, Richards DA, Scott EM, Southon JR, Turney CSM, van der Plicht J. IntCal13 and MARINE13 radiocarbon age calibration curves 0-50000 years calBP. Radiocarbon 55(4). DOI: 10.2458/azu_js_rc.55.16947

License:

This code is licensed under the GNU GENERAL PUBLIC LICENSE - see the LICENSE file for details