Radiocarbon dating is only accurate for objects
Of course, for a small examples like this, no computer programs are needed to find the best ordering, but for larger data sets like the 900 graves studied by Petrie they are extremely helpful.
The contexts were labeled in chronological order by numbers 01 to 60, the types are labeled in the form T00001 to T00050.
The raw data are stored in an unsorted binary contingency table indicating which design style can be found in which context by a star symbol.
For example, consider the first column: context 3 contains the design styles blackrim, bottle, and handle. Contextual seriation sorts the design styles and the contexts in such a way that the star symbols are found as close as possible to the diagonal of the table.
Errors in typology result in errors in seriation: For example, if a certain design style had two peaks in popularity (bimodal distribution), this design style is not appropriate for seriation and its inclusion in the analysis may result in strange results.
Some design styles were used for a very long time as the shape constructed was handy and no improvement or ornament was added.Contextual seriation is often used for reconstructing the chronological sequence of graves as only the presence or absence of a design style or type is important.