Archaeologists call this kind of behavior "curation" -- people then, just like today, like to hang on to old things.
Seriation, also called artifact sequencing, is an early scientific method of relative dating, invented (most likely) by the Egyptologist Sir William Flinders Petrie in the late 19th century.
Petrie's problem was that he had discovered several predynastic cemeteries along the Nile River in Egypt that seemed to be from the same period, but he needed a way to put them in chronological order.
The figure on this page is a Microsoft Excel (TM) table showing the results of our frequency count.
Our next step is to create a bar graph of the percentages of the objects in our junkyard samples.
What this step does is create a visual representation of the qualities of the artifacts, and their co-occurrence at different junkyards.
Notice that this figure does not mention what kind of artifacts we're looking at, it just groups similarities.The seriation method works because object styles change over time; they always have and always will.A good example of a change in artifact type is the development of hand-held PDAs from those first enormous cell phones. As an example of how change through time works, consider the different music recording methods that were used in the 20th century.Using seriation at our hypothetical junkyard sites, we will try to establish the chronology--the order in which the junkyards were used and closed.To start out, we will take a sample of the deposits in each of junkyards.Microsoft Excel (TM) has created for us a lovely stacked bar graph for us.