DAACS Seriation Method
DAACS staff aim to produce a seriation-based chronology for each slave-quarter site using the same methods (see Neiman, Galle, and Wheeler 2003 for technical details). Only assemblages from features or stratigraphic groups with more than five ceramic sherds are included in these ceramic-based seriations. Plowzone contexts do not contribute to a DAACS seriation-based chronology. Since none of the features at Site 7 contained more than 5 ceramic sherds, DAACS was unable to produce a seriation-based chronology for the site. However, the site-wide Mean Ceramic Date points to the occupation’s temporal placement in the third and fourth quarters of the eighteenth century.
Two other measures that are less sensitive to excavation errors and taphonomic processes that might introduce a small amount of anomalously late material into an assemblage were used. They are TPQp90 and TPQp95. The TPQp95 of 1775 provides a robust estimate of the site's TPQ based on the 95th percentile of the beginning manufacturing dates for all the artifacts comprising it. The TPQp90 of 1762 provides a more robust estimate of the site's TPQ based on the 90th percentile of the beginning manufacturing dates for all the artifacts comprising it.
Recent research using Correspondance Analysis (CA) that included ceramics from plowzone contexts suggests that there are four assemblage groups present at Site 7 (Neiman, and Smith 2005). In plotting the physical locations of these assemblage groups, Neiman and Smith discovered that they were spatially correlated with different residential areas on the site, suggesting that each assemblage group represents a discrete residential group. The Neiman and Smith (2005) scientific poster is available on the Research page for download.
Site 7 Mean Ceramic Date and TPQs