Page 86 - IJPS-7-2

International Journal of

Population Studies

Report
Modeling, simulating, and comparing biased

archaeological mortuary assemblages

C. L. Kieffer*
Department of Anthropology, University of New Mexico, Albuquerque, New Mexico, USA

Abstract

This paper uses a novel approach to compensate for inherent sampling biases and to
compare the age profiles of two ancient Maya sacrificial assemblages to expectations
from a model life table for traditional horticultural populations. It seeks to statistically
rule out the possibility that either site is accumulated due to a standard mortality
process experienced in horticulturalist populations. This analysis utilizes data from
Midnight Terror Cave (MTC), Belize and Chichén Itzá (CI), Mexico to compare the
observed versus expected death counts by age. Monte-Carlo based estimates of
preservation bias were modeled assuming a normal distribution with mean and
variance based on expert opinion. This model was used to up-adjust age-specific
death counts for both sites to make more robust sample sizes, which were compared
to those expected from a model life table at the 5 , 50 , and 95 percentiles of
th
th
th
the resampled distribution of preservation bias. At low levels of estimated bias
(5 percentile), neither MTC nor CI assemblages could be distinguished from
th
the null-mortality model. At average to higher levels of estimated bias (50 and
th
95 percentiles), both populations could be statistically distinguished from the
th
*Corresponding author: null mortality model either across all age intervals or within specific age ranges.
C. L. Kieffer (Kieffer@unm.edu) After accounting for preservation bias, the findings suggest that both MTC and CI
Citation: Kieffer C. L., (2021). assemblages were unlikely to have accumulated due to a normal mortality pattern
Modeling, simulating, and experienced within traditional horticulturalist populations, further supporting
comparing biased archaeological
mortuary assemblages. the ethnographic and archaeological evidence that indicates that the sites are
International Journal of Population accumulated due to cultural practices related to human sacrifice.
Studies, 7(2):80-92.
https://doi.org/10.36922/ijps.v7i2.300
Keywords: Mortuary assemblages; Siler model; Monte Carlo simulation; Preservation
Received: June 11, 2022
bias; Sampling bias; Sacrifice; Maya Bioarchaeology
Accepted: November 10, 2022
Published Online: November 25,
2022
Copyright: © 2022 Author(s). 1. Introduction
This is an Open Access article
distributed under the terms of the The previous examinations of the Midnight Terror Cave (MTC) site, Belize, have
Creative Commons Attribution concluded that there is strong archaeological evidence suggesting that the assemblage
License, permitting distribution, is accumulated due to cultural practices associated with human sacrifice (Kieffer,
and reproduction in any medium,
provided the original work is 2011; 2015; 2018). The assemblage associated with Chichén Itzá (CI), Mexico, is
properly cited. widely considered being accumulated primarily due to human sacrifice practices
Publisher’s Note: AccScience (de Anda Alanís, 2007; Tozzer, 1941; Tiesler, 2005). However, to date no research
Publishing remains neutral with has ruled out the possibility that either site is accumulated due to a typical mortality
regard to jurisdictional claims in
published maps and institutional pattern associated with horticultural populations. This study fills the existing gap in
affiliations. the literature by making a statistical comparison between sacrificial assemblages and

Volume 7 Issue 2 (2021) 80 https://doi.org/10.36922/ijps.v7i2.300