Paleodemographic age‐at‐death distributions of two Mexican skeletal collections: A comparison of transition analysis and traditional aging methods

Abstract

Traditional methods of aging adult skeletons suffer from the problem of age mimicry of the reference collection, as described by Bocquet-Appel and Masset (1982). Transition analysis (Boldsen et al., 2002) is a method of aging adult skeletons that addresses the problem of age mimicry of the reference collection by allowing users to select an appropriate prior probability. In order to evaluate whether transition analysis results in significantly different age estimates for adults, the method was applied to skeletal collections from Postclassic Cholula and Contact-Period Xochimilco. The resulting age-at-death distributions were then compared with age-at-death distributions for the two populations constructed using traditional aging methods. Although the traditional aging methods result in age-at-death distributions with high young adult mortality and few individuals living past the age of 50, the age-at-death distributions constructed using transition analysis indicate that most individuals who lived into adulthood lived past the age of 50.

Validation of transition analysis as a method of adult age estimation in a modern South African sample

“…The imprecision was partly attributed to the effects of individual and population differences between the test population and both the reference sample and the prior distribution [2,15,16]. Other researchers reached similar conclusions using single skeletal regions to test the transition analysis statistics method [17][18][19].…”

“…Although transition analysis [1] has improved age estimation from the skeleton, researchers validating the method were disappointed by the accuracy of the point estimate values and the age ranges [2,5,15,16], which were comparable with less complex multifactorial methods such as multiple linear regression [3]. The imprecision was partly attributed to the effects of individual and population differences between the test population and both the reference sample and the prior distribution [2,15,16].…”

La esperanza de vida en la ciudad de México (siglos XVI al XIX)

“…Estudios previos reportan un componente biológico mayoritariamente indígena en estos esqueletos, pero también destacan algunos individuos con rasgos de morfología dental propios de las poblaciones europeas, que nos hacen pensar corresponden a los primeros mestizos, pues la cronología asignada por los análisis arqueológicos la colocan a fines del siglo xvi (Karam, 2012). Esta serie está integrada por 384 individuos, de los cuales casi 50% son menores de quince años, lo que permite obtener cálcu-los estadísticos de mortalidad infantil (Bullock, Márquez, Hernández y Velasco, 2013;Civera, 2005;Hernández, 2006a;Márquez y Hernández, 2006;Medrano, 2006).…”

Maximum likelihood estimate of life expectancy in the prehistoric Jomon: Canine pulp volume reduction suggests a longer life expectancy than previously thought

“…Since this distribution is unknown (after all this is what we are trying to estimate) an alternative approach, which provisionally assumes some age distribution as the prior probability distribution, has been applied (Bullock, M arquez, Hern andez, & Ruíz, 2013;DeWitte, 2010;Nagaoka, Sawada, & Hirata, 2008;Storey, 2007). The Bayes theorem requires a prior distribution for the calculation, and in a strict sense this should be the age distribution of deaths of the target population.…”