A mean ceramic date offers a quick and rough indication of the chronological position of a ceramic assemblage (South 1977). The mean ceramic date for an assemblage is estimated as the weighted average of the manufacturing date midpoints for the ceramic types found in it. The weights are the frequencies of the respective types in the assemblages. Types represented by more sherds have greater influence in the calculation. Manufacturing midpoint estimates, and the beginning and ending manufacturing dates from which they are computed, come from documentary evidence on the ceramic industry.
Here we offer two different mean ceramic date queries. The first provides mean ceramic dates for the chosen level of aggregation. The second provides ware-type frequencies. The data in each query are generated using traditional ceramic ware types such White Salt Glaze, Creamware, Pearlware, Chinese Porcelain, and American Stoneware. The manufacturing date range for each ware type was assigned using traditional documentary sources (e.g. Noel Hume 1969, Miller et al. 2000).
- Mean Ceramic Date Query 1: By contexts, feature numbers, feature types, feature groups, stratigraphic groups, phases or sites
Mean Ceramic Dates are calculated for Contexts, Feature Numbers, Feature Types, Feature Groups, Stratigraphic Groups, Phases, or Sites. Choose the site or sites and the level at which you would like to calculate the mean ceramic date.
- Mean Ceramic Date Query 2: Ware-Type Frequencies
Provides ceramic ware-type frequencies for individual Contexts, Feature Numbers, Feature Types, Feature Groups, Stratigraphic Groups, Phases, or Sites. Choose the site or sites and the level at which you would like to aggregate the ware-type frequencies.
Citing Your Query
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Please provide the following information in a bibliography when citing data from DAACS.
- The query from which data was used, e.g. Artifact Query 1.
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Why Documenting Your Query is Important.
The DAACS database is periodically updated to include data from newly analyzed archaeological sites. Since data in the database may change after an update, it is important for a researcher to record the database version used when querying.
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