Notes on some statistical aspects of pottery quantification

The quantification of finds assemblages from excavations, as an aid to the comparative study of assemblages and sites, is a developing and increasingly important aspect of post-excavation analysis. In the area of pottery studies a major influence has been the work of Clive Orton and Paul Tyers, culminating in the recent release of the 'pie-slice' package for computer analysis. Much of the published literature is either highly technical, or of an expository nature which needs a great deal of the technical material and underlying assumptions to be taken on trust. The present paper is intended to be intermediate between these two levels. We address some of the more complex or less obvious issues involved in application of the pie-slice 'philosophy'. A worked example is given to highlight aspects of some of the assumptions and calculations involved. Some attention is given to what can be done outside the pie-slice package. One concern is the analysis of assemblages that have been quantified using estimated vessel equivalents (eves), but not in a manner that allows conversion to pottery information equivalents (pies) in the pie-slice package

Notes on the statistical analysis of some loomweights from Pompeii

Recent work, in the field, on the dimensions and weights of loomweights from excavations in Insula VI.I, Pompeii suggested – to our surprise – that there was structure in the form of evidence of bi-modality in the weights. The paper has two purposes. One is to illustrate a variety of statistical methods that were used to confirm the validity of our observations. The other is to discuss what the archaeological implications of this might be. A more general point is that if more attention is given to what are often regarded as “uninteresting” artefacts some interesting results may emerge - specifically, it can be asked whether loomweights have chronological significance for interpreting archaeological sites (at Pompeii at least)

Compositional data analysis in archaeometry

We shall call an n × p data matrix fully-compositional if the rows sum to a constant, and sub-compositional if the variables are a subset of a fully-compositional data set1. Such data occur widely in archaeometry, where it is common to determine the chemical composition of ceramic, glass, metal or other artefacts using techniques such as neutron activation analysis (NAA), inductively coupled plasma spectroscopy (ICPS), X-ray fluorescence analysis (XRF) etc. Interest often centres on whether there are distinct chemical groups within the data and whether, for example, these can be associated with different origins or manufacturing technologiesGeologische Vereinigung; Universitat de Barcelona, Equip de Recerca Arqueomètrica; Institut d’Estadística de Catalunya; International Association for Mathematical Geology; Patronat de l’Escola Politècnica Superior de la Universitat de Girona; Fundació privada: Girona, Universitat i Futur

Compositional data analysis of archaeological glass: problems and possible solutions

Presentation in CODAWORK'03, session 4: Applications to archeometryGeologische Vereinigung; Universitat de Barcelona, Equip de Recerca Arqueomètrica; Institut d’Estadística de Catalunya; International Association for Mathematical Geology; Patronat de l’Escola Politècnica Superior de la Universitat de Girona; Fundació privada: Girona, Universitat i Futur