Spatial and Multivariate Analysis, Random Sampling Error, and Analytical Noise: Empirical Bayesian Methods at Teotihuacan, Mexico

Abstract

Methods of empirical Bayesian statistical inference can help archaeologists deal with problems inherent in variably-sized and, particularly, small artifact samples. The desirability of systematically controlling random effects of sampling error when mapping estimates of artifact type proportions is emphasized in this paper, and concrete examples are provided using ceramic data from the Central Mexican city of Teotihuacan. A Bayesian approach also may be beneficial for pretreating data destined for other kinds of quantitative analysis, such as exploratory multivariate analysis. Correspondence analysis using observed proportions of different types of pottery in assemblages pertaining to the Xolalpan and Metepec phases produces vague results that suggest little in the way of interpretable structure. However, a parallel analysis using posterior estimates of proportions reveals meaningful associations of ceramic categories that appear to relate to more general dimensions of behavioral variability.