Ancient Latin America Lectures: Ivan Ghezzi

Refining Khipu Absolute Chronology via Bayesian Modeling: New Evidence from the Santa Valley Archive

Author and Coauthors: Ivan Ghezzi (Unidad Ejecutora Chankillo, Ministerio de Cultura; Universidad de Piura), Manuel Medrano (Harvard University), Dominika Sieczkowska (Silesian University of Technology), Jacek Pawlyta (Silesian University of Technology), Alcides Alvarez (Instituto de Investigaciones Arqueológicas IDARQ), Alan G. Hogg (University of Waikato, School of Science), Fiona Petchey (Radiocarbon Dating Laboratory, University of Waikato), Andrzej Rakowski (Silesian University of Technology), Andres Chirinos (PhD candidate, UNED of Spain)

In this presentation, we share the first results from a collaborative project aimed at refining the calibration of absolute dates for khipus through Bayesian modeling. We survey the existing radiocarbon initiatives in the field, which reveal an inconsistent landscape that has not yet made full use of contextual information and advanced statistical models. We present here one of our current case studies: the analysis of new samples from the colonial-era “Santa Valley Archive” of khipus. By combining new and previous radiocarbon dates and applying Bayesian modeling during calibration, we refine the chronology of these well-known specimens to a span of a few decades. We discuss the implications of our results for the proposed decipherment of the Santa Valley Archive, and reflect on the ways in which more intentional modeling of radiocarbon dates can play an active role in the description, analysis, and decipherment of khipus.

Zoom link: https://yale.zoom.us/j/98856670429
51 Hillhouse Ave rm 101
Lunch will be provided