title: A generative inference framework for analysing patterns of cultural change in sparse population data with evidence for fashion trends in LBK culture.
abstract: Cultural change can be quantified by temporal changes in frequency of different cultural artefacts and it is a central question to identify what underlying cultural transmission processes could have caused the observed frequency changes. Observed changes, however, often describe the dynamics in samples of the population of artefacts, whereas transmission processes act on the whole population. Here we develop a modelling framework aimed at addressing this inference problem. To do so, we firstly generate population structures from which the observed sample could have been drawn randomly and then determine theoretical samples at a later time t2 produced under the assumption that changes in frequencies are caused by a specific transmission process. Thereby we also account for the potential effect of time-averaging processes in the generation of the observed sample. Subsequent statistical comparisons (e.g. using Bayesian inference) of the theoretical and observed samples at t2 can establish which processes could have produced the observed frequency data. In this way, we infer underlying transmission processes directly from available data without any equilibrium assumption. We apply this framework to a dataset describing pottery from settlements of some of the first farmers in Europe (the LBK culture) and conclude that the observed frequency dynamic of different types of decorated pottery is consistent with age-dependent selection, a preference for 'young' pottery types which is potentially indicative of fashion trends.
authors.affiliation: Department of Mathematics, City University London, Northampton Square, London EC1V 0HB, UK Santa Fe Institute, 1599 Hyde Park Road, Santa Fe, NM 87501, USA anne.kandler.1@city.ac.uk.
authors.forename: Anne
authors.initials: A
authors.lastname: Kandler
authors.affiliation: Institute of Archaeology, University College London, 31-34 Gordon Square, London WC1H 0PY, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Shennan
mesh_terms: D018929:Cell Culture Techniques; D008954:Models, Biological
keywords: age-dependent selection; approximate Bayesian computation; cultural transmission; frequency-dependent selection; neutral evolution; statistical inference