The final map (Figure 6) presents a series of terms extracted from the titles and abstracts of the research papers within the refined list that have been mapped and clustered. VOSviewer identified 287,000 terms that have been used at least once, and, as was the case with the previous maps, this number decreases rapidly when the threshold for the number of times used is raised. Approximately 3000 terms were used 21 times or more, and just over 1200 terms have been used more than 50 times (see Table 7). For the map presented here, the threshold for the inclusion was again set at 50 times, resulting in a map with 1153 terms as nodes. VOSviewer has identified 12 separate clusters (minimum cluster size: 10 terms; clustering resolution: 1.55), the largest of which contains 253 terms and the smallest 36 terms. On the basis of the terms included within each cluster, it is possible to identify themes for each of these clusters (Table 8).
|Number of Terms||Times used (2004-2013)|
Unsurprisingly, the largest cluster is comprised of terms that make up what we might call the common language of archaeology as a discipline in the Arts and Humanities. This common language includes archaeology and archaeologist of course, but also includes such terms as society, community, meaning, materiality, discourse, ethnicity, text, power, theory and heritage. The next largest cluster contains what might be called the language of archaeology as a scientific practice, with terms related to laboratory practice as well as statistical analysis; sample, technique, mineral, concentration, provenance, and mean, principal components analysis and so forth. In addition to this general scientific language there are smaller clusters containing the concepts and vocabulary of specialist forms of scientific analysis in archaeology; the language of scientific dating, the language of chemical analysis, and of dietary analysis, and of populations and genetics all presenting as small distinct clusters. It is also unsurprising given the interest shown by archaeologists in their physical context that there are two large clusters of terms related to landscape analysis and environmental change, as well as landscape survey and geophysics. In a similar fashion to the network maps of sources and authors, there is a distinct cluster of terms that separates out the study of human evolution or palaeoanthropology. The most surprising cluster, perhaps, is a group of terms that seem to form the language of a discussion of the origins of plant cultivation and animal husbandry including species, agriculture, cultivation, phytolith, crop and Neolithic.
|Cluster no.||'Theme'||No.||Major terms included in this cluster.|
|1||The core language of 'Archaeology'||253||archaeology, archaeologist, community, person, project, practice, society, tradition, material culture, concept, meaning, heritage, theory|
|2||Scientific practice and archaeology||163||sample, technique, composition, concentration, temperature, object, fragment, spectroscopy|
|3||Landscape analysis and environmental change||156||deposit, sediment, Holocene, landscape, basin, climate, soil, river, dynamic, climate change|
|4||Landscape survey and geophysics||106||application, measurement, surface, mapping, field survey, geographical information system, geophysical investigation, landscape archaeology|
|5||Palaeoanthropology and human evolution||101||assemblage, early hominin, Pleistocene, Palaeolithic, adaptation, hunter gatherer, marine isotope stage, oxygen isotope stage, subsistence strategy, taphonomy||6||Populations and genetics||74||population gene, sequence, ancient DNA, mitochondrial DNA, diversity, lineage, domestication, animal|
|7||Human remains||63||cemetery, grave good, human remain, pathology, trauma, violence, weapon, sex determination|
|8||The Classical and medieval worlds||59||building, museum, monument, house, Roman world, Greek, castle, inscription|
|9||Chemical analysis in archaeology||54||biomarker, lipid, extraction, fatty acid, organic residue, ceramic vessel, gas chromatography|
|10||Archaeology and the study of diet||51||diet, stable isotope analysis, consumption, seasonality, mobility|
|11||Dating in archaeology||37||radiocarbon dating, thermoluminescence, tree ring, osl age|
|12||The origins of agriculture and animal husbandry||36||species, agriculture, economy, phytolith, starch grain, cereal, farming, Neolithic, micromorphology|
Readers wishing to examine this map online can do so by following this link to the network map of terms (the online viewer works best with Internet Explorer).
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