Differentia similarity scores by manuscript

Thesis reference
Figure 4.3

Explore similarity of manuscripts' differentia. The similarity score considers the ratio of shared differentiae between two sources. If none of the differentiae in manuscript A appear in manuscript B, it would suggest that the chant traditions of the two manuscripts are unrelated; if all of the differentiae in A are also in B, it would suggest that there is an extremely close connection between the two. Similarity scores for all manuscripts in the Differentiae Database were calculated by calculating the average of two ratios: (1) number of shared differentiae between A and B to the total number of differentiae in A; and (2) number of shared differentiae between A and B to the total number of differentiae in B.

For example, CH-Fco 2 has 44 unique differentiae and D-Ma 12o Cmm 1 has 52 unique differentiae; 27 differentiae appear in both manuscripts. Therefore, CH-Fco 2 and D-Ma 12o Cmm 1 have a similarity score of 0.57 [(27/44 + 27/52)/2]. As each score approaches 1.00, the level of similarity between two manuscripts increases. Each manuscript has a score of 1.00 with itself.

The graph and map in this visualization are coloured according to the similarity score. To view the similarity scores for each manuscripts, select a manuscript from the drop-down menu at the top left. The degree of similarity can be altered using the sliding bar to the right. To highlight the location of each of the manuscripts, select a manuscript in the graph.