Archeologia e Calcolatori 8 - 1997

The rapid spread of Geographical Information Systems (GIS) technology confronts archaeologists with a number of opportunities and several dilemmas. Presentations and discussions at the 1996 UISPP meeting in Forlì, Italy, suggested that the current contributions of GIS to archaeological zeitgeist mixes new analytical possibilities, new data management capacities and theoretical problems. The current debate surrounding these issues is useful, yet it ignores several important areas of discussion. Many of the peculiarities of spatial data and spatial analysis have so far been overlooked, as have the changing metaphors of time and space demanded by GIS. A host of entertaining possibilities await those prepared to explore some of the remoter horizons opened by GIS.

Recent studies have emphasised the usefulness of a jointed employment, in historical and archaeological research, of the most advanced computer technologies with statistical methods. In this work, as an application of a Geographical Information System (GIS), we present a Matlab language program for the statistical analysis of spatial data related to ancient human settlements. The explanation of the program is preceded by some notes about the GIS, the area from which data have been collected, and the statistical methods applied to analyse the data.

The aim of this paper is to introduce a class of testable statistical models aimed at modelling archaeological sites locations (ASL) or a continuous space and at producing probability maps of ASL. These models are based on collected statistical and auxiliary information (such as information about the slope or exposure of the land, the topography, the hydrology, the topology, etc.). More explicitly the model for the ASL is based on the assumption that the location of the existing archaeological sites is fixed and that the location of new archaeological sites not yet found is a realization of a non-stationary point process depending on the spatial interaction with other existing sites, on the distance from important location or communication networks, and on a set of auxiliary variables. It is also possible to introduce into the discussion information we have about the archaeological site dimensions. In fact, it is plausible that the interaction between existing archaeological sites and candidate locations for new archaeological sites is dependent on their dimension. These models can prove valuable in that they formalize some “common sense” knowledge and can help in producing automated probability maps on a continuous space to support excavation decisions.

Within the framework of the ANITES methodology, designed for the study of the spatial articulation of the archaeological record, we use a remodelled version of the nearest-neighbour in 3D, that computes the distances between three-dimensional points (x, y, z). In this paper we present some technical questions related to performances for the study of the distribution patterns and for the determination of the spatial category groups. We use a comparison between the results obtained in different data processing (El Cingle Vermell, El Roc del Migdia, Túnel VII and Punta Baja sites) to evaluate the relationships and incidence of the variables involved (values of the coefficient R, critical distance, number of effective and number of category groups). This technical evaluation shows that the test of the nearest-neighbour in 3D works for our expectation and is very useful when inserted in the framework of the ANITES methodology.

Geophysical techniques applied to archaeological exploration involve specific problems of data interpretation, due to the spatial characteristics that they possess and to the particularities of material remains in archaeological sites. This work shows an application of statistical spatial analysis to the study of data in 2D coordinates together with the value of a variable z, that quantifies a spatial soil characteristic (in the magnetometric survey these values correspond to the magnetic intensity or gradient values). The analysis includes exploratory statistical non-spatial methods and other methods extracted from the statistical spatial analysis, and performs thematic maps by means of a new algorithm that finds the greater contrasts in the z values. This methodology and the algorithm have been applied to the microspatial study of magnetometric data in a Roman settlement in Las Gabias (Granada, Spain) and verified with the excavation carried out on this site.

The archaeological aim of this paper is to demarcate the groups of graves within the particularly random distribution of a Greek archaic cemetery: the west necropolis of Megara Hyblaea, excavated by Paolo Orsi in 1889. The methodological aim is to observe the behaviour of four different statistical analyses applied to the same data. The selected methods take the variable of space into account, meaning: the exact location where each data has been measured (a grave is a unit). Finally, concerning graves and their location, the following question is posed: is it possible to build one typology of archaeological characteristics through the description of the procedures with which the space has been occupied?

The authors identify different kinds of variability in the production of artefacts: a series of socially accepted types within a certain class of products; individual variations due to a low degree of control in the manufacture; sporadic variations for the desire for variation; variations linked to phenomena of auto-identification of single or a few producers and users versus other ones; chronological variations. The authors attempt to make connections between the different kinds of associations of features highlighted by chi square analysis in the ceramic assemblage of Conelle and those kinds of variability.

Non-parametrical tests have been used to check the validity of some hypothesis made of archaeological material (sealings on papyri kept in a Delian archive destroyed by a fire in 69 BC). Although these tests deal only with a part of the corpus, the validity of the results should not be questioned.

Besides allowing the visualisation of architecture from the past through the use of images, either virtual or real, virtual restitution in architecture implies the use of analytical methodologies that serve the purpose of a better understanding of architectural space as well as its genesis. The restitution contributes both to the process of building an appropriate tridimensional model adequate for multiple uses, and to the output of new information as the restitution process develops. In the present work, the applied methodological approach is discussed in relation to a virtual restitution of the Mesoamerican archaeological site of Cacaxtla leading to an idealisation of its original condition.

The main subject of this article is the problem of the filing of textual data in archaeology in order that they can be analysed and processed automatically. This problem is closely associated to another topic, that of text encoding. An electronic text may contain more than one markup level. The first one is the character encoding, usually the ASCII - 7 bit set, that offers 127 bit combination to represent letters, digits and a few other signs. The ASCII code has the advantage of being a standard valid for every operating system. It is therefore suggested, to encode other signs not included in the ASCII set, the use of a combination of the 127 available characters rather than a combination of 8 bit (256 possible combinations), because the number codes greater than 127 are used for different signs on different systems. A document file may contain another markup that encodes format parameters. To transform a simple document into a “database” where information can be searched and retrieved, the conceptual components must be encoded. The Standard Generalized Markup Language appears to be a good tool to produce files that are software and hardware independent, easy to be managed and ready to be automatically analysed by a software in order to retrieve pieces of information.

The Internet is increasingly becoming a tool fundamentally important and effective archaeological research. Archaeology is an appropriate subject through which to promote the use of electronic media as it is multidisciplinary, with a wide range of data types. Resources offered by the Internet provide a means of sharing and distributing information of many different kinds in many different ways. Actually, archive material – ranging from field survey data, excavations and museum collections to ancient sources – are being made available through the web. The author presents the most interesting sites (key sites, electronic journals and above all museums) available on web, and discusses problems and difficulties of conducting research via the Internet. The WWW could change radically the way in which archaeologists communicate the results of their work, both for the benefit of other archaeologists and the wider public. On-line journals, for example, could be an important tool to solve printed media problems and difficulties for editing archaeological reports. Museums could be seen as the most important virtual place to visit in order to explore the world and its history. Unfortunately, current archaeological museum sites often restrict themselves to provide only basic and general information (addresses, exhibits, virtual tours) aimed at a large rather than a professional public. The Internet is never going to replace real museums or archaeological sites; it is going to be supplementary.

Multimedia is increasingly spreading through many different fields (research, didactics, entertainment) but the meaning of this word is not always clear. The term multimedia can actually signify two things: something that is spread through different media, or a product that contains more than one media and that can thus transmit other and more complicated information. In this paper the second meaning is discussed. A list of projects is offered in order to present the state of the art in research on multimedia. Three topics are examined: a) implementation of conceptual models to plan and produce multimedia: the same models can be used at the same time to evaluate an applet; b) benefits of multimedia application in didactics; c) what kind of multimedia products are mainly requested in Cultural Heritage.