radio-rian logo — Newgrange kerbstone lozenges

radio-rian

dátú, dating · rian, a trace — a cleaned corpus of Irish radiocarbon dates

Of the published Irish radiocarbon record — some 10,665 determinations in Chapple’s 2019 catalogue — the number ever formally Bayesian-modelled is in the low hundreds, and no published Irish application of rcarbon’s significance tests could be found. The bottleneck is not the statistics. It is that the corpus is not in a state where anyone can run them.

radio-rian does the unglamorous part. It takes Chapple’s catalogue — a genuine act of scholarship, and the only thing of its kind — and makes it analysable: a controlled site-type vocabulary, the calibration metadata recovered, the ages recalibrated against IntCal20, the record cross-checked against every other compilation, and extended past Chapple’s 2019 cut-off. The cleaning decisions are the contribution, and every one is recorded and reviewable.

Provisional. The reservoir classification, the site-type vocabulary and the reliability flags are machine-generated first passes (decided_by=rule) awaiting human review. The dataset is usable and honest about what it is, but the review passes are not yet complete — see the caveats on each page. Do not treat the reservoir/soundness flags as final.

In one screen

11,634
determinations — 10,665 from Chapple + 969 extended past 2019
54,287
IntCal20 highest-density calibrated intervals (multimodality preserved)
9,280
classified as soundly terrestrial and recalibrated; the rest flagged, not mis-calibrated
1,508 → ASI
free-text site-type strings mapped to the national monument classification
6 + 143
likely transcription errors and duplicate-lab-code collisions surfaced in the source
Map of Irish radiocarbon determinations coloured by age
The corpus, coloured by uncalibrated age. The distribution follows the road corridors — a property of development-led archaeology that matters for any demographic reading.

What’s here

Everything is open data. Built on Chapple 2019 (CC-BY-4.0); see the footer for full attribution.