However, it has some advantages regarding the other techniques, as it also reveals the internal structure of the data when no seriation is present, thus being appropriate for cluster analysis.
Cases defined by a small set of variables usually appear separated from the main body of the parabola, and usually correspond to ill defined cases which can be removed from the analysis, which sometimes improves the seriation (fig.
Once a seriation or clustering is detected, it is the archaeologist's task to determine its meaning: it usually has chronological implications but can also represent social, wealth or gender variations, for example.
The results of the correspondence analysis were fairly good, as the diagram showed a parabolic curve which marked the existence of a seriation within the data, with three main groups and a prolongation of one of the legs of the parabola (fig.
As the seriation progresses, the round-ended hilts still appear, but the midrib disappears, and sometimes a grip and ricassos are visible.
Not only has it proved the existence of a stylistic seriation within the engravings, but it has allowed us to establish a preliminary overview of the engravings with several possible chronological phases.
Considering the small size of the sample, the results were astonishingly good, based on the representation of an almost symmetric parabola that clearly points to the existence of a seriation underlying the data (fig.
Thus, although the evidence of a seriation is undeniable, the results were less operational than those achieved with the weapons (fig.
The absence of chronological criteria within the sample implied that the seriation could be read from both sides, thus leaving the interpretation open and subsequently useless.
In this case its ascription to a prehistoric chronology is more dubious, since the Correspondence Analysis places it at the end of the seriation, thus being one of the newest depictions in the whole sample.